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	2022-12-14: How Can Matter Be BOTH Liquid AND Gas? 00:03: ... - like how at very high emperatures we get the plasma that the sun is made of, or at extreme densities we get the nuclear matter of neutron ... 18:29: These neutrinos would now have energies 10 billion times smaller than regular neutrinos, say from the Sun. 19:30: The limit for the Milky Way’s black hole is around 100-billion times brighter than the Sun. 19:37: ... limit would be about 3 times brighter on our sky compared to the Sun. ...
	2022-11-23: How To See Black Holes By Catching Neutrinos 01:03: They report seeing neutrinos produced in the colossal magnetic fields surrounding a black hole with the mass of 10 million Suns. 02:38: By far the brightest neutrino source on the sky is the Sun. 06:02: The sun produces an enormous number, but those are easy to distinguish because they come from the direction of the Sun. 08:30: In this case with a mass of around 10 million suns. 11:00: The only other sure neutrino detections from space are the Sun and the remnant of supernova 1987A in the large magellanic cloud. 06:02: The sun produces an enormous number, but those are easy to distinguish because they come from the direction of the Sun. 01:03: They report seeing neutrinos produced in the colossal magnetic fields surrounding a black hole with the mass of 10 million Suns. 08:30: In this case with a mass of around 10 million suns.
	2022-11-09: What If Humanity Is Among The First Spacefaring Civilizations? 07:07: ... will only be habitable for another 1 billion years, after which the sun will be too hot for liquid water to exist on the surface of the ... 07:49: ... known as red dwarfs, can live for thousands of times longer than our sun, meaning they could have planets that remain habitable for trillions of ...
	2022-10-26: Why Did Quantum Entanglement Win the Nobel Prize in Physics? 15:49: There was the one about using the Sun’s gravitational field as a lens to take pictures of distant planets. 17:03: Well there’s no real range limit in terms of  what planets will be brought to a focus in the sun’s gravitational focal range. 17:37: The report talks about Earth-mass planets around Sun-like stars, of which there are plenty. 15:49: There was the one about using the Sun’s gravitational field as a lens to take pictures of distant planets. 17:03: Well there’s no real range limit in terms of  what planets will be brought to a focus in the sun’s gravitational focal range. 15:49: There was the one about using the Sun’s gravitational field as a lens to take pictures of distant planets. 17:03: Well there’s no real range limit in terms of  what planets will be brought to a focus in the sun’s gravitational focal range. 15:49: There was the one about using the Sun’s gravitational field as a lens to take pictures of distant planets. 17:03: Well there’s no real range limit in terms of  what planets will be brought to a focus in the sun’s gravitational focal range.
	2022-10-12: The REAL Possibility of Mapping Alien Planets! 00:03: ... light to a magical point out there in space  where the Sun’s own gravity turns it into a   gigantic lens. What could such ... 01:25: ... directly along the line connecting your favorite exoplanet and the Sun, but away from   them both, you’ll reach this spot where light ... 04:36: ... like this   galaxy being lensed by an intervening galaxy. The sun also has a gravitational field that would   create an Einstein ... 06:05: ... 45 years and is   now around 150 astronomical units from the Sun. To get a telescope to the SGLF we’d want it to travel   a ... 07:45: ... as we’ll see, it actually gets very close   to the Sun, and C) is only a few hundred atoms thick so it doesn’t blow out our ... 09:31: ... sufficiently heat resistant. Then the craft then whip around the Sun and set their sails   squarely against that intense up-close ... 10:07: ... While a regular lens creates a focal point,   the Sun’s gravitational field creates a focal line, starting at 550 ... 14:06: ... the surfaces of distant worlds, brought into focus by our own Sun and its lens of curved ... 10:07: ... want to do with a telescope is to point it at   the Sun - that’s a great way to fry your  camera - and good luck seeing ... 06:05: ... 45 years and is   now around 150 astronomical units from the Sun. To get a telescope to the SGLF we’d want it to travel   a bit faster ... 10:07: ... motion of the   exoplanet but also due to the wobble of the Sun as its tugged by the planets of our solar system.   Our telescope ... 06:05: ... it with the very clean, well-understood gravitational field of our Sun.   All we need to do is get our telescope to  the right spot. ... 09:31: ... sort of tack inwards. They speeds up rapidly plummeting towards the Sun,   ideally at around a quarter of Mercury’s  orbital radius, assuming ... 10:07: ... going to execute this shifting pirouette as it races away from the Sun,   and that entire dance will have to be performed without any ... 09:31: ... sort of tack inwards. They speeds up rapidly plummeting towards the Sun,   ideally at around a quarter of Mercury’s  orbital radius, assuming we can ... 10:07: ... travel time, slowly expanding outwards as we get further from the Sun.   Remember that the scientists called this  a string of pearls. That first ... 00:03: ... light to a magical point out there in space  where the Sun’s own gravity turns it into a   gigantic lens. What could such ... 10:07: ... While a regular lens creates a focal point,   the Sun’s gravitational field creates a focal line, starting at 550 ... 00:03: ... chance of actually happening.  A train of spacecraft sailing the sun’s   light to a magical point out there in space  where the Sun’s own ... 01:25: ... spot where light rays from the exoplanet are bent inwards by the Sun’s   gravitational field to all come together. Forget about a New York ... 00:03: ... chance of actually happening.  A train of spacecraft sailing the sun’s   light to a magical point out there in space  where the Sun’s own gravity ... 07:45: ... are  proposing an advanced solar sail design called   the SunVane - multiple controllable sail panels mounted along the narrow ...
	2022-09-14: Could the Higgs Boson Lead Us to Dark Matter? 01:18: ... a hundred trillion neutrinos emitted by the sun pass through your body every second, but you don’t notice because they ...
	2022-06-22: Is Interstellar Travel Impossible? 06:08: ... the Milky Way disk is around 1 atom per cubic centimeter, however the Sun is in an under-dense region called the local ...
	2022-05-25: The Evolution of the Modern Milky Way Galaxy 02:19: ... Milky Way is a pretty typical barred  spiral galaxy. Our sun is in the disk,   on a minor outcropping of one of the ... 06:32: ... 10 billion years ago. This merger was so  large - around 50 billion Suns worth of matter -   that it must have reshaped the galaxy and ... 07:58: ... arms and the big, bright star forming clouds   and our sun. We did an episode on why galaxies  become flat disks - but the TLDW ... 11:10: ... of these passes even happens to line up  with the formation of our sun and solar system   4.5 billion years ago. Now, we’re not ... 06:32: ... 10 billion years ago. This merger was so  large - around 50 billion Suns worth of matter -   that it must have reshaped the galaxy and ...
	2022-05-18: What If the Galactic Habitable Zone LIMITS Intelligent Life? 00:24: ... enough ultraviolet light for photosynthesis.   If the sun contained significantly less heavy elements it could never have ... 01:07: ... is the Sun unique enough to explain one of  the most perplexing mysteries of ... 01:36: ... as well as being an expert in folklore.  Who better to compare the Sun’s uniqueness   from the perspectives of science versus  our ... 02:06: ... a modern astronomer’s perspective,  our Sun is objectively mediocre,   average in terms of mass, age, ... 02:20: ... war, but nothing is more important to our survival   than the sun. So it’s no surprise  that nearly every ancient culture   ... 02:52: ... of the seasons. To the Maori people   of New Zealand, the Sun was personified  by the God Tamanuitera. In one story,   ... 03:29: This myth paints and others about the sun paint a nice picture of its importance. 03:34: But pf course, modern science has  its own origin story for our nearest and dearest star, the sun. 03:40: ... Sun formed around 5 billion years ago, collapsing from an overdense ... 04:32: ... star has a pretty cool backstory, but  hardly a unique one. Our Sun is a pretty ordinary   G-type main sequence star. Around 5% of ... 06:56: ... it seems that to really understand the  Sun’s uniqueness, we need to take our story   back even further - ... 11:12: ... Way’s formation history, our  starting intuition seems right: the Sun and solar   system are NOT special as far as our galaxy ... 12:04: ... most of them - 75% - have been around longer  than the Sun - by an average of a billion   years. So if our analysis of ... 00:24: ... enough ultraviolet light for photosynthesis.   If the sun contained significantly less heavy elements it could never have formed a ... 03:40: ... Sun formed around 5 billion years ago, collapsing from an overdense lump of ... 03:29: This myth paints and others about the sun paint a nice picture of its importance. 01:07: ... is the Sun unique enough to explain one of  the most perplexing mysteries of the ... 00:24: ... requirements   has nothing to do with the planet. Our Sun  also seems pretty ideal in a number of ways.   A bit more ... 02:20: ... our distant ancestors, the Sun  was a wondrous source of warmth,   light, food, and stability. ... 12:04: ... what did they find? As we suspected, the Sun  is not unique, but it’s also not the most typical.   Fewer ... 01:07: ... we’ve talked about  before. But one possible solution is that the Sun   and its planetary system are really quite unique  in its ability to ... 03:40: ... up in the shrinking  spheroid that would ultimately become our Sun,   a fraction of the material collapsed  into a disk around the ... 01:36: ... as well as being an expert in folklore.  Who better to compare the Sun’s uniqueness   from the perspectives of science versus  our ... 06:56: ... it seems that to really understand the  Sun’s uniqueness, we need to take our story   back even further - ... 01:36: ... as well as being an expert in folklore.  Who better to compare the Sun’s uniqueness   from the perspectives of science versus  our own slightly biased ...
	2022-03-23: Where Is The Center of The Universe? 03:04: General relativity can be used to calculate the spacetime curvature produced by the Earth or the Sun to determine their gravitational effects.
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 01:28: ... alpha-cen sway relative to the background stars as Earth orbited the Sun. ... 01:47: The two stars were so near and so familiar - both within 10% or so of our own Sun’s mass. 03:05: This one was barely a star at all, really, at only 12% of the Sun’s mass and only a little larger than Jupiter. 06:29: That sounds perilous, until you realize that Proxima’s energy output is nearly 600 times lower than the Sun’s. 12:32: By the way, unlike the Sun which grows brighter over time, red dwarfs fade. 14:28: After all, Proxima, with its many-trillion-year lifespan will far outlive our own Sun. 03:12: Hardly exciting compared to its vibrant, Sun-like siblings. 08:36: ... much  more tentative detections   of planets around its Sun-like siblings - a Neptunish body may have been imaged around Rigel Kentaurus ... 03:12: Hardly exciting compared to its vibrant, Sun-like siblings. 08:36: ... much  more tentative detections   of planets around its Sun-like siblings - a Neptunish body may have been imaged around Rigel Kentaurus ... 03:12: Hardly exciting compared to its vibrant, Sun-like siblings. 08:36: ... much  more tentative detections   of planets around its Sun-like siblings - a Neptunish body may have been imaged around Rigel Kentaurus and an ... 01:47: The two stars were so near and so familiar - both within 10% or so of our own Sun’s mass. 03:05: This one was barely a star at all, really, at only 12% of the Sun’s mass and only a little larger than Jupiter. 06:29: That sounds perilous, until you realize that Proxima’s energy output is nearly 600 times lower than the Sun’s. 01:47: The two stars were so near and so familiar - both within 10% or so of our own Sun’s mass. 03:05: This one was barely a star at all, really, at only 12% of the Sun’s mass and only a little larger than Jupiter.
	2022-01-27: How Does Gravity Escape A Black Hole? 02:28: Imagine for a moment that the Sun just disappeared. 02:46: It would take 8 minutes for the Sun’s deep indentation in the fabric of space to smooth itself - in the wake of some pretty crazy gravitational waves. 03:42: ... example, when Earth feels the pull of the Sun’s gravity - it’s not directly interacting with the Sun itself, it’s ... 02:46: It would take 8 minutes for the Sun’s deep indentation in the fabric of space to smooth itself - in the wake of some pretty crazy gravitational waves. 03:42: ... example, when Earth feels the pull of the Sun’s gravity - it’s not directly interacting with the Sun itself, it’s ... 02:46: It would take 8 minutes for the Sun’s deep indentation in the fabric of space to smooth itself - in the wake of some pretty crazy gravitational waves. 03:42: ... example, when Earth feels the pull of the Sun’s gravity - it’s not directly interacting with the Sun itself, it’s interacting ...
	2022-01-19: How To Build The Universe in a Computer 00:42: The event I just described will happen as surely as the Sun will rise tomorrow.
	2022-01-12: How To Simulate The Universe With DFT 15:37: Most likely the black hole was moving faster than 42 km/s - that would only be the case if it had exactly the same galactic orbit as the sun. 15:57: ... multiple interactions on its way to the Earth - perhaps it punctured the Sun, swung around Jupiter, etc, and lost speed that ... 16:21: And speaking of black holes hitting the Sun, Christian asks whether that would be detectable. 16:32: ... for the sun and Jupiter it’s marginally possible that if you were looking at the ... 18:10: ... Dyson sphere reprocessing a sun’s visible light into infrared, ultimately releasing exactly as much energy ... 16:21: And speaking of black holes hitting the Sun, Christian asks whether that would be detectable. 15:57: ... multiple interactions on its way to the Earth - perhaps it punctured the Sun, swung around Jupiter, etc, and lost speed that ... 18:10: ... Dyson sphere reprocessing a sun’s visible light into infrared, ultimately releasing exactly as much energy ...
	2021-12-29: How to Find ALIEN Dyson Spheres 01:00: ... of room to expand if we were to cover the entire sphere surrounding the Sun with the radius of Earth’s orbit, we’d collect all of the Sun’s light - ... 01:16: The idea of wrapping the sun in solar collectors is not new. 02:49: It doesn’t reflect nearly as much of the Sun’s light as you’d expect for a globe of water and rock - it's as though that energy is being sucked up. 03:05: ... the Sun produces a thermal spectrum - light generated by its 6000K surface is ... 03:36: ... incredibly sensitive telescope to pick the Earth’s faint glow from the Sun’s overwhelming ... 03:05: ... the Sun produces a thermal spectrum - light generated by its 6000K surface is distributed ... 01:00: ... the Sun with the radius of Earth’s orbit, we’d collect all of the Sun’s light - a billion times more than what we’d get just covering the planet ... 02:49: It doesn’t reflect nearly as much of the Sun’s light as you’d expect for a globe of water and rock - it's as though that energy is being sucked up. 03:36: ... incredibly sensitive telescope to pick the Earth’s faint glow from the Sun’s overwhelming ... 01:00: ... the Sun with the radius of Earth’s orbit, we’d collect all of the Sun’s light - a billion times more than what we’d get just covering the planet in ... 02:49: It doesn’t reflect nearly as much of the Sun’s light as you’d expect for a globe of water and rock - it's as though that energy is being sucked up. 01:00: ... the Sun with the radius of Earth’s orbit, we’d collect all of the Sun’s light - a billion times more than what we’d get just covering the planet in ... 03:36: ... incredibly sensitive telescope to pick the Earth’s faint glow from the Sun’s overwhelming ...
	2021-12-20: What Happens If A Black Hole Hits Earth? 07:40: ... Witnesses described a stripe of light in the sky as bright as the sun and a thunderous sound like cannons that leveled trees and broke windows ...
	2021-12-10: 2021 End of Year AMA! 00:02: ... they're giant stars so you know many many times larger than our sun and they pulsate they pulsate in brightness and they pulsate in size ...
	2021-11-17: Are Black Holes Actually Fuzzballs? 01:34: ... large number - 10^10^77 bits for a black hole the mass of our Sun. ...
	2021-11-02: Is ACTION The Most Fundamental Property in Physics? 06:47: ... equations of motion correctly describing the orbit of Mercury around the Sun. ...
	2021-10-13: New Results in Quantum Tunneling vs. The Speed of Light 04:03: ... necessary for the nuclear fusion reactions that power the sun, in some biological processes, and it’s even a critical part of the ...
	2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe 01:42: ... fields are a billion  times stronger than those of the earth or sun. ... 04:04: ... a white dwarf - the dead core of a lower   mass star like our Sun. The plasma is crushed so tight that electrons are on the verge ... 02:00: ... is very different from  the magnetized space around the earth or sun.   It’s filled with electrons and  positrons. These ...
	2021-09-07: First Detection of Light from Behind a Black Hole 03:13: ... the universe - anything more than a million or so times the mass of the Sun. ... 11:33: ... of good stuff like measuring the mass of the black hole - 30 million Suns - to verifying Einstein’s general theory of ...
	2021-08-03: How An Extreme New Star Could Change All Cosmology 01:45: ... the final fate of any star less than 8 or so times the mass of the Sun. ... 03:19: ... fields. Fields around a billion times stronger than the earth or sun’s magnetic field. That’s at the top tier of the most magnetic white ... 05:51: ... comparison, a white dwarf the mass of our sun would be around the size of the earth, this new guy is barely 25% bigger ... 08:05: ... quantum mechanics, it was found that it must weigh in at 1.32 times the Sun’s mass. And that’s a lot, at least for a white dwarf. We’ve known for some ... 14:14: ... of this show. Without your support and enthusiasm, we’d probably have sunk to space-themed reaction videos and quantum mechanics based pranks. As ... 03:19: ... fields. Fields around a billion times stronger than the earth or sun’s magnetic field. That’s at the top tier of the most magnetic white ... 08:05: ... quantum mechanics, it was found that it must weigh in at 1.32 times the Sun’s mass. And that’s a lot, at least for a white dwarf. We’ve known for some ... 03:19: ... fields. Fields around a billion times stronger than the earth or sun’s magnetic field. That’s at the top tier of the most magnetic white ... 08:05: ... quantum mechanics, it was found that it must weigh in at 1.32 times the Sun’s mass. And that’s a lot, at least for a white dwarf. We’ve known for some time ...
	2021-07-21: How Magnetism Shapes The Universe 00:43: Threads tugged lightly towards the Earth, tightly towards the Sun, or into inescapable knots towards black holes. 03:44: But while we’re here, it’s worth following one of Earth’s field lines that connects directly to the surface of the Sun. 03:53: Here the field is generated by electrical currents flowing in the searing plasma near the Sun’s surface. 04:05: But the Sun is entirely fluid, and its rate of rotation speeds up towards the equator. 04:21: We can see those tangled field lines in ultraviolet light as charged particles spiral along them, up and down from the Sun’s surface. 04:49: This is still the Sun’s magnetic field, which connects here and there to the piddling little fields of the planets. 04:55: About 4x the distance to Pluto, the Sun’s magnetic field connects to the field of the galaxy itself. 05:03: This is the heliopause, the boundary of the heliosphere, which defines the limit of the Sun’s influence in the galaxy. 05:11: Although it’s less of a sphere and more of a teardrop - dragged into that shape by the Sun’s orbital motion through the galaxy. 03:53: Here the field is generated by electrical currents flowing in the searing plasma near the Sun’s surface. 04:21: We can see those tangled field lines in ultraviolet light as charged particles spiral along them, up and down from the Sun’s surface. 04:49: This is still the Sun’s magnetic field, which connects here and there to the piddling little fields of the planets. 04:55: About 4x the distance to Pluto, the Sun’s magnetic field connects to the field of the galaxy itself. 05:03: This is the heliopause, the boundary of the heliosphere, which defines the limit of the Sun’s influence in the galaxy. 05:11: Although it’s less of a sphere and more of a teardrop - dragged into that shape by the Sun’s orbital motion through the galaxy. 05:03: This is the heliopause, the boundary of the heliosphere, which defines the limit of the Sun’s influence in the galaxy. 04:49: This is still the Sun’s magnetic field, which connects here and there to the piddling little fields of the planets. 04:55: About 4x the distance to Pluto, the Sun’s magnetic field connects to the field of the galaxy itself. 04:49: This is still the Sun’s magnetic field, which connects here and there to the piddling little fields of the planets. 04:55: About 4x the distance to Pluto, the Sun’s magnetic field connects to the field of the galaxy itself. 05:11: Although it’s less of a sphere and more of a teardrop - dragged into that shape by the Sun’s orbital motion through the galaxy. 03:53: Here the field is generated by electrical currents flowing in the searing plasma near the Sun’s surface. 04:21: We can see those tangled field lines in ultraviolet light as charged particles spiral along them, up and down from the Sun’s surface.
	2021-05-11: How To Know If It's Aliens 06:27: ... the same way that comets do due to outgassing - ices vaporizing in the Sun’s radiation acting like jets. In the case of comets, this also results in ...
	2021-04-21: The NEW Warp Drive Possibilities 10:39: The energy required to carry a 100-meter diameter bubble is about the rest-mass energy of a tenth of our Sun.
	2021-04-13: What If Dark Matter Is Just Black Holes? 05:13: ... and could be anything from a grain of salt to tens of thousands of suns. ... 05:43: The most massive black holes in the universe weigh in at millions to billions of times the mass of our Sun. 08:52: ... MACHOs between roughly the moon’s mass to 10 or so times the mass of the Sun as a main contributor to dark ... 09:30: So far we’ve mostly ruled out black holes around the Sun’s mass or lower as an explanation for dark matter. 10:20: ... - if there were lots of black holes of several tens times the Sun’s mass then these binaries would long ago have been torn apart by close ... 05:13: ... and could be anything from a grain of salt to tens of thousands of suns. ... 09:30: So far we’ve mostly ruled out black holes around the Sun’s mass or lower as an explanation for dark matter. 10:20: ... - if there were lots of black holes of several tens times the Sun’s mass then these binaries would long ago have been torn apart by close ... 09:30: So far we’ve mostly ruled out black holes around the Sun’s mass or lower as an explanation for dark matter. 10:20: ... - if there were lots of black holes of several tens times the Sun’s mass then these binaries would long ago have been torn apart by close ...
	2021-03-16: The NEW Crisis in Cosmology 07:28: ... measure the distance to stars. As the earth orbits the   sun over the course of the year, nearby stars appear to move relative ...
	2021-03-09: How Does Gravity Affect Light? 11:43: ... measure the slight offset in the apparent positions of stars around the sun, due to their light rays being “refracted” in the Sun’s gravitational ...
	2021-02-17: Gravitational Wave Background Discovered? 00:00: ... a few different ways black holes with masses of millions to billions of suns live in the cores of most galaxies these super massive black holes can ...
	2020-12-22: Navigating with Quantum Entanglement 02:04: Across long distances, birds often rely on the sun or even the stars. 15:10: ... Russell’s teapot is a hypothetical piece of chinaware that orbits the sun between the earth and mars, and which science has yet to prove doesn’t ...
	2020-12-15: The Supernova At The End of Time 02:20: But first, there are many questions to be answered - like how do stars including our Sun end up as one of these “iron stars” in the first place? 04:43: It had become clear that this must be the Sun’s ultimate fate. 06:24: ... behind by an ordinary star that should be 1.44 times the mass of the Sun. ... 08:02: ... inside the crystalized black dwarf that our Sun will become, a single carbon or oxygen nucleus has been sitting neatly ... 08:29: ... is called pycnonuclear fusion - and it will very VERY slowly convert the Sun’s core from carbon into the most stable form of matter - iron - over ... 10:48: times the Sun’s mass. 11:28: And the remnants of our solar system get to see all of this - our Sun stays a black dwarf - probably of crystalized iron - through all of this. 04:43: It had become clear that this must be the Sun’s ultimate fate. 08:29: ... is called pycnonuclear fusion - and it will very VERY slowly convert the Sun’s core from carbon into the most stable form of matter - iron - over ... 10:48: times the Sun’s mass. 08:29: ... is called pycnonuclear fusion - and it will very VERY slowly convert the Sun’s core from carbon into the most stable form of matter - iron - over around ... 10:48: times the Sun’s mass. 04:43: It had become clear that this must be the Sun’s ultimate fate.
	2020-10-05: Venus May Have Life! 00:59: It’s the brightest thing in the sky besides the sun and moon, hanging just above sunrise and sunset. 01:12: In many ways it’s Earth’s twin - it’s even inside that band around the Sun where liquid water is possible - the so-called habitable zone. 02:22: ... other weird thing is that the clouds of Venus appear to absorb the Sun’s light in a weird way - more short wavelength visible and UV light is ... 13:48: And, ultimately, to ally with them in war against the cosmic string entities in the heart of the Sun that we discussed recently. 00:59: It’s the brightest thing in the sky besides the sun and moon, hanging just above sunrise and sunset. 02:22: ... other weird thing is that the clouds of Venus appear to absorb the Sun’s light in a weird way - more short wavelength visible and UV light is ... 00:59: It’s the brightest thing in the sky besides the sun and moon, hanging just above sunrise and sunset.
	2020-09-28: Solving Quantum Cryptography 16:25: Some of you thought it was funny that we would do an episode on life in the sun right after the potential discovery of life on venus. 16:42: ... don't you think it's important to understand possible life in the sun before we decide what diplomatic relations to develop with the ... 16:52: Well, Celsius notes that these sun creatures would have had a very different experience in their scientific development. 16:08: There’s david brin’s sundiver, and Frank Herbert's "Whipping Star", and several more.
	2020-09-21: Could Life Evolve Inside Stars? 08:35: For example, life uses the energy flowing from the high energy-density of the Sun to the lower energy density of the Earth. 11:28: ... of cosmic strings and monopoles, visiting Earth from the core of the Sun to help spread cosmic ...
	2020-09-08: The Truth About Beauty in Physics 01:26: Nicholaus Copernicus found more beauty of simplicity by placing the Earth along with all planets in simple circular orbits around the Sun. 14:42: That's the case when looking through the Sun's atmosphere at it's bright interior.
	2020-09-01: How Do We Know What Stars Are Made Of? 00:28: ... first thing you learn in astronomy is that the sun and the other stars are giant balls of fiery hydrogen and helium, ... 03:06: ... is a modern spectrum of the Sun - it’s the amount of light we receive at different colors - or in other ... 03:15: Most of this light comes the photosphere - a layer around 100 km deep at the surface of the Sun. 03:26: The colour of a star depends on that temperature - blue for hot stars, red for cooler stars, and sort of greenish-yellow for stars like our Sun. 03:51: A photon trying to escape from inside the Sun encounters a lot of obstacles. 03:56: One of the most severe is that the Sun is full of free electrons - electrons that were stripped from their atoms due to the intense heat. 04:12: ... photon coming from the core of the Sun will be or scattered so many times that what should be a 1-second ... 05:07: So any photons trying to escape the Sun that happen to have one of these particular energies are going to get sucked up on its way out. 05:26: Just seeing which absorption lines are present tells you which elements are present inside the Sun. 05:32: ... the spectrum of the Sun was first studied, it was noticed that the most prominent lines ... 05:41: The prevailing wisdom came to be that the sun was made of exactly the same stuff as the Earth - just a lot, lot hotter. 05:48: ... to test this - to figure out the true composition of the sun from these absorption lines - was going to take some serious advances in ... 06:38: In energetic environments like the Sun, electrons are regularly kicked free from their atoms. 07:38: ... one thing, each absorption line is formed as light deeper within the sun traverses a large distance, over which temperature and pressure drop ... 09:05: Her results suggested that hydrogen was by far the most common atom in the sun, followed closely by helium. 09:13: Cecilia Payne had discovered what the sun and stars were made of. 09:18: This was totally against the current scientific consensus - which was that the Sun was made of the same stuff as the Earth. 09:39: ... the fact of the sun being made mostly of hydrogen and helium was confirmed only a few years ... 03:06: ... is a modern spectrum of the Sun - it’s the amount of light we receive at different colors - or in other ... 06:38: In energetic environments like the Sun, electrons are regularly kicked free from their atoms. 03:51: A photon trying to escape from inside the Sun encounters a lot of obstacles. 07:38: ... one thing, each absorption line is formed as light deeper within the sun traverses a large distance, over which temperature and pressure drop ...
	2020-08-24: Can Future Colliders Break the Standard Model? 07:25: ... energies - for example using natural particle accelerators like the sun or supernovae or quasars or galactic magnetic fields, which continuously ... 15:59: ... who don't know - the Chandrashekar limit is 1.4 times the mass of the sun - it’s the maximum mass of a white dwarf before crushing gravitational ...
	2020-08-17: How Stars Destroy Each Other 00:20: When our galaxy was a little younger there were two ordinary stars - perhaps not unlike our sun, and they danced together in binary orbit. 06:42: The nearest such system is the famous Cynus X1 X-ray binary, where a black hole the mass of 15 Suns is busy gorging on a blue giant star.
	2020-07-28: What is a Theory of Everything: Livestream 00:00: ... the perihelion shift the mercury the bending of starlight around the sun all sorts of general relativity stuff with ligo and gravitational ...
	2020-07-20: The Boundary Between Black Holes & Neutron Stars 01:14: One was a hefty 23 times the mass of our Sun - making it definitely a black hole, and pretty similar to other LIGO mergers. 05:11: So you end up with at least one and a half suns worth of matter locked in a ball that would fit inside a small city. 08:00: Those models have predicted maximum masses in the range 2 to 3 times the mass of the sun. 08:59: But, the most massive so far is around 2.1 Suns. 09:33: So far we’ve never observed a black hole with masses lower than around 5 times that of the Sun. 10:28: Based on our calculations and simulations of how stars die, that minimum black hole mass of 5 Suns seems about right. 01:14: One was a hefty 23 times the mass of our Sun - making it definitely a black hole, and pretty similar to other LIGO mergers. 05:11: So you end up with at least one and a half suns worth of matter locked in a ball that would fit inside a small city. 08:59: But, the most massive so far is around 2.1 Suns. 10:28: Based on our calculations and simulations of how stars die, that minimum black hole mass of 5 Suns seems about right. 05:11: So you end up with at least one and a half suns worth of matter locked in a ball that would fit inside a small city.
	2020-07-08: Does Antimatter Explain Why There's Something Rather Than Nothing? 05:43: ... anti-electrons - are created all the time in nature - for example in the Sun, or in radioactive decay, or when cosmic rays hit the atmosphere, which ...
	2020-05-11: How Luminiferous Aether Led to Relativity 02:33: ... flows carried the celestial bodies, for example in circles around the Sun. The Dutch physicist Christiaan Huygens developed a detailed mathematical ... 08:02: ... lab when you already have a fast-moving planet? Earth hurtles around the Sun at 30 km/s - that’s only one one hundredth of one percent of the speed ...
	2020-04-28: Space Time Livestream: Ask Matt Anything 00:00: ... piece of art okay it's a it's a beautiful time to see it because the Sun shines off the gold leaf but what is it where did it come from well ...
	2020-04-14: Was the Milky Way a Quasar? 00:47: ... is it home to an enormous black hole four million times the mass of the Sun, but it also swarms with smaller black holes, searing hot clouds of gas, ... 08:16: Now A full quasar might devour many millions of times the mass of the Sun over one active period, which could last for several million years. 15:59: ... and was able to announce triumphantly that the Earth was created on Sunday the 21th of October, 4004 B.C., at exactly 9:00 A.M., because God liked ...
	2020-04-07: How We Know The Earth Is Ancient 11:55: ... solar system meteorites and also from our calculations of the age of the Sun. ... 12:35: ... Canyon. Not that our ancient Earth cares - it’s revolved around the sun 4.5 billion times through deep space and out of deep time, and it’ll do ...
	2020-02-11: Are Axions Dark Matter? 08:58: ... then they should be produced in reasonable quantities in the core of the sun. There, X-rays are constantly bouncing off electrons and protons in the ...
	2020-01-27: Hacking the Nature of Reality 15:56: ... black holes a few tens of millions to 10 billion times the mass of the sun - and the small end of that range is indeed a "little" compared to the ...
	2020-01-20: Solving the Three Body Problem 04:12: ... solar system can be thought of as a separate two-body system with the Sun. That gives you a series of simple elliptical orbits, like those ... 04:29: ... be used to approximate the orbits of the moon relative to the Earth and Sun, or the Earth relative to the Sun and ... 05:01: ... mass, and the solar system as a whole has many massive constituents. The Sun, Jupiter and Saturn alone are automatically a three-body system with no ... 06:43: ... it will stay there indefinitely, tracking the Earth’s orbit around the Sun. We now call these the Lagrange points, and they’re useful places to park ... 05:01: ... mass, and the solar system as a whole has many massive constituents. The Sun, Jupiter and Saturn alone are automatically a three-body system with no analytic ... 12:00: ... so long after Poincare stern proclamation, Finnish mathematician Karl Sundman found a solution to the general three-body ... 12:21: ... the equation could be written out on paper. However the convergence of Sundman’s series is so slow that it would 10^8 million terms to converge for a ...
	2020-01-13: How To Capture Black Holes 00:24: ... lit up the sky, When we learned to see in neutrinos the core of the Sun became visible to us. But now that our vision extends to gravitational ... 02:50: ... supermassive black hole of millions to billions of times the mass of the Sun. Recently we’ve also learned that the galactic center likely also ... 07:17: ... mass” black holes can form, with 1000s of times the mass of the Sun. ...
	2020-01-06: How To Detect a Neutrino 02:05: ... thick to have a 50/50 chance at stopping a single neutrino from the Sun. ...
	2019-12-17: Do Black Holes Create New Universes? 10:08: Lee Smolin calculates that optimized cutoff at around 2 times the mass of the Sun.
	2019-11-18: Can You Observe a Typical Universe? 00:34: ... the center of the universe into just one of several planets orbiting the Sun. ... 00:45: ... our astronomy improved, we realized that our sun is a typical example out of 100s of billions of stars in the Milky Way, ... 12:13: ... been made to have me in it!" This is such a powerful idea that as the sun rises in the sky and the air heats up and as, gradually, the puddle gets ...
	2019-11-11: Does Life Need a Multiverse to Exist? 06:21: ... of the key steps in the fusion process inside stars - so stars like our sun wouldn’t burn at ...
	2019-11-04: Why We Might Be Alone in the Universe 04:31: ... about the size of the Earth in orbit around stars very similar to the Sun at the right distance to sustain liquid water on their surface - in the ... 08:32: ... emerging as a primordial soup sloshed in these pools, baking in the sun. ...
	2019-10-07: Black Hole Harmonics 08:09: ... GW150914 – a pair of black holes, each 30 or so times the mass of the sun, spiraling into each other one and a half billion light years ...
	2019-09-30: How Many Universes Are There? 16:42: If Earth formed at 100 times its current distance from the sun it wouldn't have cleared its orbit either, and so wouldn't be considered a planet. 16:55: ... somewhat complicated relationship between mass and distance from the Sun that determines whether you get called a planet - and that relationship ... 17:22: That brings us to the first part of the IAU definition - a planet has to be orbiting our Sun. 16:01: Here the IAU definition again: "A planet is a sun-orbiting body massive enough to be round and to have cleared it's orbit of debris".
	2019-09-23: Is Pluto a Planet? 01:44: ... included Mercury, Venus, Mars, Jupiter, and Saturn, but also the sun and the moon - basically anything that moved relative to the background ... 02:07: ... published “On the Revolutions of the Heavenly Spheres” which cast the Sun, not the Earth, as the center of the universe and the Earth in its proper ... 02:34: The solar system finally made observational and theoretical sense: there were now 6 planets orbiting the sun in perfect mathematical harmony. 09:02: A planet must: One - be in its own orbit around the Sun, not around another planet like a moon. 16:27: ... that's a long time for any photosynthesizing life to survive without the sun, and 2) it has essentially no water, so we'd have to be bringing all of ...
	2019-09-16: Could We Terraform Mars? 01:47: Light from the Sun, which is already fainter due to Mars’ distance – is radiated directly back out into space. 02:15: And of course Earth’s atmosphere protects us from harmful cosmic rays and the most dangerous ultraviolet radiation from the Sun. 13:19: The easiest would be to do that in space – an orbiting field generator placed between Mars and the Sun, like a giant space umbrella. 18:23: Electrical currents are induced and these produce a magnetic field that pushes back against the Sun's magnetic field.
	2019-09-03: Is Earth's Magnetic Field Reversing? 00:46: Now, that’s helpful, because Earth is constantly bombarded by very fast moving charged particles, especially coming from the Sun. 07:27: ... a fluid conductor can produce such a field – the Earth, but also the Sun with its flowing hydrogen plasma, or the liquid metallic hydrogen in ...
	2019-07-25: Deciphering The Vast Scale of the Universe 06:23: ... Earth, the Sun, and our solar system behind, we’re zipping past the hundreds of billions ...
	2019-07-01: Thorium and the Future of Nuclear Energy 00:33: ... force holding nuclei together contains an enormous amount of energy The Sun is powered that way Releasing a mere 0.4 percent of the mass of hydrogen ...
	2019-06-20: The Quasar from The Beginning of Time 06:24: ... hole. That allows us to estimate the mass of the black hole: 800 million Suns. ... 06:39: If it replaced our Sun, it would easily swallow Saturn's orbit. 06:24: ... hole. That allows us to estimate the mass of the black hole: 800 million Suns. ...
	2019-06-17: How Black Holes Kill Galaxies 00:08: ... could have masses of Millions or even Billions of times that of the Sun It came as a bit of a shock they were discovered as the driving force ... 04:05: ... less than a Billion years after the Big bang with masses of 10 Billion suns Easily as large as the largest in the modern Universe so if Black Holes ...
	2019-05-16: The Cosmic Dark Ages 07:19: ... first supermassive black holes with millions, even billions of times the Sun’s mass – inescapable spheres the size of solar systems. And in the final ...
	2019-05-09: Why Quantum Computing Requires Quantum Cryptography 15:41: Munrais asks whether putting radio telescopes around the sun would improve the resolution of an interferometer. 05:48: ... photon through a horizontal polarization filter like a polarized sunglasses lens and the photon will either decide it’s vertically polarized and be ... 06:19: Try it with two polarized sunglasses lenses at 90-degrees – all light gets blocked. 05:48: ... photon through a horizontal polarization filter like a polarized sunglasses lens and the photon will either decide it’s vertically polarized and be ... 06:19: Try it with two polarized sunglasses lenses at 90-degrees – all light gets blocked. 05:48: ... photon through a horizontal polarization filter like a polarized sunglasses lens and the photon will either decide it’s vertically polarized and be ... 06:19: Try it with two polarized sunglasses lenses at 90-degrees – all light gets blocked.
	2019-05-01: The Real Science of the EHT Black Hole 01:00: It has an estimated mass of several billion times that of the Sun, which gives it an event horizon larger than the solar system.
	2019-04-24: No Dark Matter = Proof of Dark Matter? 00:03: ... orbits they inferred a mass for Fritz of 130 million times that of our Sun although with an error bar of 18 million solar masses the comparison our ...
	2019-01-24: The Crisis in Cosmology 03:53: ...whose distances can be figured using stellar parallax Tracking their tiny motions on the sky, as Earth orbits the Sun.
	2018-12-06: Did Life on Earth Come from Space? 00:37: ... boring journey ahead to get to the nearest stars a rock traveling at the sun's galactic orbital speed of 30 km/s would take several tens of thousands ...
	2018-11-21: 'Oumuamua Is Not Aliens 00:29: ... of our solar system drifting on their endless orbits around the sun, and faintly glimmering with its reflected ... 00:48: It was not in orbit around the sun at all. 02:56: It appears to be accelerating, or at least it's not slowing down as much as you'd expect due to the sun's gravitational pull. 03:20: Comets show the same sort of acceleration on their way out from the sun. 03:27: As the sun heats the rear surface of the comet, water, ice, and frozen gases, so-called volatiles, evaporate. 04:32: The sun's own light could be pushing on the object speeding it up. 04:41: The acceleration is decreasing with the square of the distance from the sun. 04:49: ... from outgassing, because outgassing also depends on the strength of the sun's ... 03:27: As the sun heats the rear surface of the comet, water, ice, and frozen gases, so-called volatiles, evaporate. 03:38: In regular comets, the outgassing is typically visible as sunlight reflects off dust carried along with the jets. 06:48: ... I mentioned that in regular comets, the coma and tail are seen through sunlight reflected off dust, tiny mineral grains that are carried out with the ... 03:38: In regular comets, the outgassing is typically visible as sunlight reflects off dust carried along with the jets. 02:56: It appears to be accelerating, or at least it's not slowing down as much as you'd expect due to the sun's gravitational pull. 04:32: The sun's own light could be pushing on the object speeding it up. 04:49: ... from outgassing, because outgassing also depends on the strength of the sun's ... 02:56: It appears to be accelerating, or at least it's not slowing down as much as you'd expect due to the sun's gravitational pull. 04:49: ... from outgassing, because outgassing also depends on the strength of the sun's radiation. ...
	2018-10-10: Computing a Universe Simulation 05:35: The mass of a 100 kilometer radius black hole would be 30 times that of our sun. 06:05: You'd need a black hole a few million times the mass of the sun and 10 million kilometers in radius.
	2018-10-03: How to Detect Extra Dimensions 04:16: We do see slight deviations in very strong gravitational fields, like close to the sun.
	2018-09-12: How Much Information is in the Universe? 07:48: Sagittarius A star in the center of the Milky Way, which has a mass of four million suns.
	2018-08-30: Is There Life on Mars? 00:43: ... the Red Planet, fourth rock from the sun, it's currently just past its closest approach to Earth, making it an ... 04:00: Mars was at its closest approach to the sun and the Earth at its closest to Mars.
	2018-08-23: How Will the Universe End? 02:13: ... will almost certainly befall the Earth, to the heating and death of the sun, to the merger with the Andromeda Galaxy, and, finally, to the death of ... 07:30: Some have grown to masses of up to 100 trillion suns, having swallowed good-sized bites from entire galaxy clusters. 07:51: The small black holes, say, around 10 times the mass of the sun, completely evaporate in around 10 to the power of 67 years. 07:30: Some have grown to masses of up to 100 trillion suns, having swallowed good-sized bites from entire galaxy clusters.
	2018-08-15: Quantum Theory's Most Incredible Prediction 13:14: And now onto your comments about getting close to the sun with the very recently launched Parker Solar Probe. 14:23: Andrea Smith asks whether the Suns million Kelvin corona temperature is caused by magnetic reconnection. 14:36: ... the mystery here is why the sun's corona, the extremely diffuse layer of material surrounding the sun, can ... 15:24: ... caused widespread auroral activity, and the big one that occurred on the sun on September 1, 1859, and reached the earth 17.6 hours ... 15:51: ... usually take several days to cross the distance between Earth and the sun, and making its effect even more powerful than if it had happened ... 14:23: Andrea Smith asks whether the Suns million Kelvin corona temperature is caused by magnetic reconnection. 14:36: ... the mystery here is why the sun's corona, the extremely diffuse layer of material surrounding the sun, can ...
	2018-08-01: How Close To The Sun Can Humanity Get? 00:00: [MUSIC PLAYING] The sun-- an entity worshiped as a god throughout time and across cultures. 00:15: ... will reach out its collective hand and come closer to touching the sun than we ever have before, with the launch of the Parker Solar ... 00:49: The Parker Solar Probe will fly within a hair's breadth of the sun itself. 00:57: The sun-- a vast ball of incandescent gas. 01:41: We still don't understand exactly why it burns at millions of Kelvin in temperature-- far hotter than the sun's surface below it. 03:09: So maybe it's a good idea to learn more about the sun's surface? 03:12: We already monitor it constantly with ground-based telescopes and spacecraft orbiting the earth or orbiting the sun at a safe distance. 03:51: It'll directly probe the sun's electromagnetic field and will connect the sun's magnetic activity with the sources of the solar wind. 04:46: Next up is the integrated science investigation of the sun or ISIS. 05:32: Together, these instruments work in tandem, creating a complete picture of the environment near the surface of the sun. 05:39: Of course, as exciting as all of this is, the big question is, how do we make sure the sun doesn't melt them? 06:12: ... challenges with this mission is getting the spacecraft that close to the sun, even ignoring its ability to survive ... 06:23: The sun's the biggest object in the solar system and has the strongest source of gravity. 06:41: ... move closer to the sun, you need to first, escape the Earth and then, lose speed, which can be ... 07:06: ... a more stretched out elliptical orbit that will take it closer to the sun. ... 07:26: By the end of 2024, if all goes according to plan, Parker will reach its closest approach to the sun of 6.2 million kilometers. 07:38: ... of its eccentric orbit, Parker will get roughly 10 times closer to the sun than the closest ... 08:06: ... seven years, Parker will have completed 26 close approaches to the sun, five of which will be a relative hair's breadth from the sun where it ... 08:30: And the dream of flying to the sun is as old as the legend of Icarus. 05:39: Of course, as exciting as all of this is, the big question is, how do we make sure the sun doesn't melt them? 01:41: We still don't understand exactly why it burns at millions of Kelvin in temperature-- far hotter than the sun's surface below it. 03:09: So maybe it's a good idea to learn more about the sun's surface? 03:51: It'll directly probe the sun's electromagnetic field and will connect the sun's magnetic activity with the sources of the solar wind. 06:23: The sun's the biggest object in the solar system and has the strongest source of gravity. 08:06: ... breadth from the sun where it will be bathed in the full force of the sun's violent ... 03:51: It'll directly probe the sun's electromagnetic field and will connect the sun's magnetic activity with the sources of the solar wind. 01:41: We still don't understand exactly why it burns at millions of Kelvin in temperature-- far hotter than the sun's surface below it. 03:09: So maybe it's a good idea to learn more about the sun's surface? 08:06: ... breadth from the sun where it will be bathed in the full force of the sun's violent ...
	2018-06-27: How Asteroid Mining Will Save Earth 06:59: Fortunately for asteroid miners, though less fortunately for the dinosaurs, many asteroids do cross Earth's orbit in their passage around the Sun.
	2018-06-20: The Black Hole Information Paradox 14:58: HebaruSan noticed that, in our graphic, the Earth completed 1.75 orbits in the supposed 8 minutes it took the Sun's gravitational field to vanish.
	2018-06-13: What Survives Inside A Black Hole? 03:54: The Earth orbits the Sun, but more directly it orbits the Sun's gravitational field. 04:00: You could change anything about the Sun other than its mass and the Earth would continue in the same orbit. 04:06: If the Sun were to suddenly vanish, Earth would continue to orbit the existing gravitational field for 8 minutes. 03:54: The Earth orbits the Sun, but more directly it orbits the Sun's gravitational field.
	2018-05-09: How Gaia Changed Astronomy Forever 01:37: The spacecraft orbits the sun at Lagrange point two, tracking the Earth's orbit, but 1.5 million kilometers further from the sun. 03:17: ... census of the stellar population far beyond the neighborhood of the sun, compared to the HR diagram of ... 10:29: On the other hand, a star that weighs twice as much as the sun, burns about 25 times brighter and burns out 10 times faster. 03:17: ... census of the stellar population far beyond the neighborhood of the sun, compared to the HR diagram of ...
	2018-05-02: The Star at the End of Time 00:25: We somehow persist through the gradual heating of our Sun and the evaporation of our oceans. 00:40: We seek refuge in the outer solar system as the Sun finally expands into a red giant twice. 00:47: And finally, our heirs or successors find new homes among the stars after the Sun's final death and transformation into a dim white dwarf. 01:55: ... Sun burns through 600 billion kilograms of hydrogen every second, generating ... 02:11: This rate will only increase as the core's temperature increases, and the Sun will burn through the hydrogen supply in its core in five billion years. 02:36: Stars less massive than the Sun burn through their fuel much more slowly. 02:41: ... also known as "M dwarfs." We observe that a red dwarf with 10% of the Sun's mass is about 1,000 times fainter than the ... 03:04: Actually, wrong-- stars like our Sun can only burn the hydrogen in their cores. 03:09: The layer above the Sun's core is what we call "radiative." All of the energy travels in the form of photons bouncing their way upwards. 03:17: Closer to the surface, the Sun becomes convective. 03:25: That radiation zone isolates the Sun's core, preventing new material from reaching those depths. 03:31: As a result, the Sun will only have access to 10% of its mass for fusion fuel. 03:58: A red dwarf with 10% the Sun's mass has just as much fuel to burn as the Sun does, yet it burns it 1,000 times slower. 04:07: That means it should live 1,000 times longer-- so 10 trillion years instead of the Sun's 10 billion years. 04:20: Just like the Sun, the cores of red dwarf stars shrink and heat up over time. 05:46: First, they shine white as their black-body spectrum spans the visible range, just like our Sun. 05:52: In the final few billion years of their lives, some red dwarfs may even become hotter than our Sun, developing a faint blue tinge. 06:58: As these brighten one by one, the most massive will shine brighter than the current Sun. 07:57: ... wharfs in the middle range of mass, around 15% of the Sun's mass, are predicted to enter a period of relatively constant brightness ... 08:06: This period could last for up to five billion years, during which the star will shine almost as bright as the Sun and quite a bit hotter. 02:36: Stars less massive than the Sun burn through their fuel much more slowly. 01:55: ... Sun burns through 600 billion kilograms of hydrogen every second, generating 4 by ... 05:52: In the final few billion years of their lives, some red dwarfs may even become hotter than our Sun, developing a faint blue tinge. 00:40: We seek refuge in the outer solar system as the Sun finally expands into a red giant twice. 06:33: ... new Sun-like stars will be born in the Milky Way/Andromeda collision four billion ... 00:47: And finally, our heirs or successors find new homes among the stars after the Sun's final death and transformation into a dim white dwarf. 02:41: ... also known as "M dwarfs." We observe that a red dwarf with 10% of the Sun's mass is about 1,000 times fainter than the ... 03:09: The layer above the Sun's core is what we call "radiative." All of the energy travels in the form of photons bouncing their way upwards. 03:25: That radiation zone isolates the Sun's core, preventing new material from reaching those depths. 03:58: A red dwarf with 10% the Sun's mass has just as much fuel to burn as the Sun does, yet it burns it 1,000 times slower. 04:07: That means it should live 1,000 times longer-- so 10 trillion years instead of the Sun's 10 billion years. 07:57: ... wharfs in the middle range of mass, around 15% of the Sun's mass, are predicted to enter a period of relatively constant brightness ... 04:07: That means it should live 1,000 times longer-- so 10 trillion years instead of the Sun's 10 billion years. 03:09: The layer above the Sun's core is what we call "radiative." All of the energy travels in the form of photons bouncing their way upwards. 03:25: That radiation zone isolates the Sun's core, preventing new material from reaching those depths. 00:47: And finally, our heirs or successors find new homes among the stars after the Sun's final death and transformation into a dim white dwarf. 02:41: ... also known as "M dwarfs." We observe that a red dwarf with 10% of the Sun's mass is about 1,000 times fainter than the ... 03:58: A red dwarf with 10% the Sun's mass has just as much fuel to burn as the Sun does, yet it burns it 1,000 times slower. 07:57: ... wharfs in the middle range of mass, around 15% of the Sun's mass, are predicted to enter a period of relatively constant brightness right ...
	2018-04-25: Black Hole Swarms 00:30: A supermassive black hole-- four million times the mass of our sun-- lurks in the center. 07:42: If the sun was near the galactic core, the nearest black hole would be inside the solar systems Oort cloud. 00:30: A supermassive black hole-- four million times the mass of our sun-- lurks in the center.
	2018-04-18: Using Stars to See Gravitational Waves 00:58: In three cases, both members of the black hole binary pair were well over 20 times the mass of the sun. 04:17: The three components of this craft will trail behind the earth in an orbit around the sun. 11:14: Without life, Earth would reflect a higher intensity spectrum closer to the 6,000 Kelvin thermal spectrum it receives from the sun.
	2018-04-11: The Physics of Life (ft. It's Okay to be Smart & PBS Eons!) 03:54: Ultimately, that source of energy is the sun. 04:08: On the other hand, the system of the Earth plus the sun is increasing in entropy. 04:46: By free energy, I mean the special out-of-equilibrium energy sources like a cup of coffee or the sun. 05:58: The water of tidal pools is both cooled by the earth and the ocean and warmed by the sun. 08:10: A plant absorbs the concentrated ultraviolet light from the sun and reprocesses it into a much higher entropy infrared heat glow.
	2018-03-28: The Andromeda-Milky Way Collision 00:38: ... hides a giant black hole that contains the mass of well over 100 million suns. ... 01:21: But what about the sun, the solar system, the Earth? 04:40: Then they averaged the observed motion of all of those stars and removed the effects due to the rotation of Andromeda and the motion of the sun. 06:50: But what about the sun and the earth? 07:22: ... der Marel, et al's, simulation follows several candidate suns, simulation particles with similar orbits and masses to our sun, and they ... 07:49: There's also a small chance that the sun will encounter one of the supermassive black holes as they descend to the core. 08:21: At this point, the sun will already have expanded into a red giant. 08:29: Earth will long ago have been roasted by our own brightening and then expanding sun, which we talked about in earlier episodes. 00:38: ... hides a giant black hole that contains the mass of well over 100 million suns. ... 07:22: ... der Marel, et al's, simulation follows several candidate suns, simulation particles with similar orbits and masses to our sun, and they ...
	2018-03-07: Should Space be Privatized? 10:31: In a recent episode, we talked about the death of the sun. 10:45: As the hydrogen fuel in the sun's core gets diluted by helium, the fusion rate does decrease and the core shrink. 11:19: By contrast, the sun is only convective in its outer layers. 11:48: ... the dramatic cycle of shell burning and red giant phases that the sun will go ... 12:04: ... stars consume their fuel thousands of times more slowly than the sun, which means they can live hundreds of times longer, even though they ... 07:45: Aerospace billionaires see themselves as the new Wright brothers and see risk and sunk investment as necessary for true innovation. 10:45: As the hydrogen fuel in the sun's core gets diluted by helium, the fusion rate does decrease and the core shrink.
	2018-02-21: The Death of the Sun 00:12: The sun has inflated to around 1 1/2 times its original size, and shines brighter than ever before. 00:34: It's time to watch the death of the sun. 01:17: That is not the fate of our sun. 01:21: The sun is now 4.6 billion years old. 01:43: ... the course of its life, the sun's core is heating, causing the sun to grow and brighten with disastrous ... 02:01: But what are the prospects for our little planet after the sun runs out of fuel? 03:09: That incredible outward flow energy does counteract gravity for the outer layers of the sun, and those layers expand. 03:17: Over the next half billion years, the sun doubles in size as a sub giant. 03:21: ... the following half billion years, the process accelerates, and the sun inflates to around the size of Venus' orbit, shining with a few thousand ... 03:45: The sun is now a red giant, and it is vast on the Earth's daytime sky. 04:20: It'll save the sun from collapsing into a black hole, and it's also currently stopping you from falling through the floor. 05:25: The energy output is insane, and the sun swells to a red giant once more. 05:41: See, the red giant sun is so large and luminous that it only has a tenuous hold on its outer layers. 05:54: ... expands, perhaps eventually taking it out beyond Mars' orbit, if the sun doesn't overtake it ... 06:08: By now, the red giant sun fills most of the sky and it's getting larger. 06:16: On the one hand, these diminish the sun's hold on us, expanding our orbit. 06:25: ... own gravitational pull creates a tidal bulge in the sun that may increase its gravitational hold on us, or the sun may just ... 06:44: It may well end up in orbit inside the sun. 07:18: The sun has become a white dwarf. 07:28: ... the Earth-- perhaps it just managed to escape the expanding sun and is now a lonely desolate world orbiting out in the old location of ... 07:46: It's also possible that the iron core survives and will continue to orbit the white dwarf sun until the end of everything. 08:47: ... moons may be a final temperate vantage point to watch the sun's inevitable death, and to look to the greater galaxy for a new home ... 05:54: ... expands, perhaps eventually taking it out beyond Mars' orbit, if the sun doesn't overtake it ... 03:17: Over the next half billion years, the sun doubles in size as a sub giant. 06:08: By now, the red giant sun fills most of the sky and it's getting larger. 03:21: ... the following half billion years, the process accelerates, and the sun inflates to around the size of Venus' orbit, shining with a few thousand times ... 02:01: But what are the prospects for our little planet after the sun runs out of fuel? 05:25: The energy output is insane, and the sun swells to a red giant once more. 01:43: ... the course of its life, the sun's core is heating, causing the sun to grow and brighten with disastrous ... 06:16: On the one hand, these diminish the sun's hold on us, expanding our orbit. 08:47: ... moons may be a final temperate vantage point to watch the sun's inevitable death, and to look to the greater galaxy for a new home ... 01:43: ... the course of its life, the sun's core is heating, causing the sun to grow and brighten with disastrous ... 06:16: On the one hand, these diminish the sun's hold on us, expanding our orbit. 08:47: ... moons may be a final temperate vantage point to watch the sun's inevitable death, and to look to the greater galaxy for a new home across far ...
	2018-02-14: What is Energy? 13:30: Well, solar system formation models do indicate a scenario in which our sun may have swallowed some early terrestrial planets. 13:45: That could have sent a new generation of planets spiraling into the sun. 13:56: If only the sun had a binary partner, we could actually test this by comparing metallicities.
	2018-01-31: Kronos: Devourer Of Worlds 00:56: Our sun wanders alone. 02:14: If we understand this chemical tagging, perhaps one day we'll be able to locate the sun's lost siblings. 03:24: They're both G-type stars like our sun. 06:18: Lithium gets depleted in the early years of stars like the sun. 07:36: ... of "Space Time." We recently discussed the gradual brightening of the sun and the inevitable extinction of all life on Earth that will result. Or ... 07:57: ... mentioned the idea of star lifting, of actually reducing the mass of the sun to reduce its luminosity and, as a side benefit, to potentially greatly ... 08:28: Andrew Milo recommends we block out some of the sun's light with orbiting solar farms. 00:56: Our sun wanders alone. 05:54: The researchers tested the hypothesis by throwing a bunch of Earth-like planets into a sun-like star-- mathematically, I mean. 02:14: If we understand this chemical tagging, perhaps one day we'll be able to locate the sun's lost siblings. 08:28: Andrew Milo recommends we block out some of the sun's light with orbiting solar farms. 02:14: If we understand this chemical tagging, perhaps one day we'll be able to locate the sun's lost siblings.
	2018-01-24: The End of the Habitable Zone 00:10: In several hundred million years, the brightening sun will turn the poles into tropical paradises. 00:25: The sun is slowly burning through its fuel. 00:27: Hydrogen is fused into helium in the sun's core, producing energy that keeps it shining and keeps the earth warm and hospitable to life. 00:36: But that fuel will run out, after which the sun will swell into a red giant and flash fry the earth. 00:48: See, the sun is getting brighter even now. 01:09: ... the sun is able to remain as a giant ball of fiery hydrogen due to a delicate ... 01:28: ... when the sun was born, it's initial gravitational collapse from a giant gas cloud was ... 01:43: At that point, the sun had plenty of hydrogen fuel. 01:49: As the sun's fuel gets diluted, you might expect fusion to slow down. 02:30: So over time, the sun's core shrinks and heats up, brightening the entire star. 02:45: It's been calculated that the sun should currently be increasing in energy output by close to 1% every 100 million years. 03:01: ... the sun was around 30% dimmer and 10% smaller when it first formed, but it will ... 03:27: But that's not the first disaster to result from the sun's brightening. 05:02: This is the distance from the sun where sustained liquid water is possible. 05:06: The brightening of the sun means the habitable zone has shifted outwards since the formation of the solar system. 05:12: ... fact, in the beginning when the sun was at 70% of its current brightness, Earth would have been outside the ... 05:36: ... prediction and the geological evidence is called the faint young sun paradox, and was pointed out by Carl Sagan and George Mullen in the ... 05:56: ... then the increased heat retention may have compensated for the fainter sun. ... 09:02: And so its ice reserves should thaw as the sun brightens. 09:26: Now we're not going to stop the sun from brightening but we might try to block some of the extra light. 09:47: ... perhaps we can hold out until the sun eventually exhausts its fuel and becomes a red giant expanding to ... 09:02: And so its ice reserves should thaw as the sun brightens. 09:47: ... perhaps we can hold out until the sun eventually exhausts its fuel and becomes a red giant expanding to consume the only ... 05:36: ... prediction and the geological evidence is called the faint young sun paradox, and was pointed out by Carl Sagan and George Mullen in the early ... 00:27: Hydrogen is fused into helium in the sun's core, producing energy that keeps it shining and keeps the earth warm and hospitable to life. 01:49: As the sun's fuel gets diluted, you might expect fusion to slow down. 02:30: So over time, the sun's core shrinks and heats up, brightening the entire star. 03:27: But that's not the first disaster to result from the sun's brightening. 00:27: Hydrogen is fused into helium in the sun's core, producing energy that keeps it shining and keeps the earth warm and hospitable to life. 02:30: So over time, the sun's core shrinks and heats up, brightening the entire star. 00:27: Hydrogen is fused into helium in the sun's core, producing energy that keeps it shining and keeps the earth warm and hospitable to life. 02:30: So over time, the sun's core shrinks and heats up, brightening the entire star. 01:49: As the sun's fuel gets diluted, you might expect fusion to slow down.
	2018-01-10: What Do Stars Sound Like? 02:03: When we try to understand other stars, we always start with our sun. 02:07: While the distance stars are infinitesimal points of light to even our best telescopes, the surface of the sun can be resolved in incredible detail. 03:24: However, it's the pressure waves-- the p-waves-- that really dominate in stars like the sun. 04:21: The strongest oscillations in the sun are in the two to four millihertz range. 04:26: These are the sun's 5-minute oscillations. 04:31: Well, for the sun, we can map these oscillations in two ways-- changes in brightness and changes in velocity. 04:38: Brightness of spectral lines in the sun's atmosphere can change by around one part per million over the course of an oscillation. 05:52: Helioseismology has allowed us to verify and improve the models of the sun's internal structure. 06:11: This differential rotation powers the sun's magnetic field and is also responsible for twisting that magnetic field to drive the sunspot cycle. 06:21: ... to measure the composition of the core, which tells us how much of the sun's hydrogen fuel source has already been burned into ... 06:31: ... this way, it's been revealed that our sun is currently around halfway through its 10-billion-year lifespan, which ... 06:42: Observations of the sun's surface are relatively easy. 07:58: But at least for the sun, it's possible to learn about current local events that are hidden from our view. 08:12: ... the distribution of Doppler velocities across the visible surface of the sun-- is used to infer the current state of the standing waves throughout the ... 08:26: That includes the far side of the sun. 08:28: In fact, helioseismic holography is capable of detecting sunspots long before the sun rotates them into visibility. 11:30: Now, it may eventually happen as the sun wanders the galaxy and encounters new neighbors, but it's still spectacularly unlikely. 08:28: In fact, helioseismic holography is capable of detecting sunspots long before the sun rotates them into visibility. 11:30: Now, it may eventually happen as the sun wanders the galaxy and encounters new neighbors, but it's still spectacularly unlikely. 04:26: These are the sun's 5-minute oscillations. 04:38: Brightness of spectral lines in the sun's atmosphere can change by around one part per million over the course of an oscillation. 05:52: Helioseismology has allowed us to verify and improve the models of the sun's internal structure. 06:11: This differential rotation powers the sun's magnetic field and is also responsible for twisting that magnetic field to drive the sunspot cycle. 06:21: ... to measure the composition of the core, which tells us how much of the sun's hydrogen fuel source has already been burned into ... 06:42: Observations of the sun's surface are relatively easy. 04:26: These are the sun's 5-minute oscillations. 04:38: Brightness of spectral lines in the sun's atmosphere can change by around one part per million over the course of an oscillation. 06:21: ... to measure the composition of the core, which tells us how much of the sun's hydrogen fuel source has already been burned into ... 05:52: Helioseismology has allowed us to verify and improve the models of the sun's internal structure. 06:11: This differential rotation powers the sun's magnetic field and is also responsible for twisting that magnetic field to drive the sunspot cycle. 06:42: Observations of the sun's surface are relatively easy. 12:18: But so would hats and sunscreen. 06:11: This differential rotation powers the sun's magnetic field and is also responsible for twisting that magnetic field to drive the sunspot cycle. 08:28: In fact, helioseismic holography is capable of detecting sunspots long before the sun rotates them into visibility. 06:11: This differential rotation powers the sun's magnetic field and is also responsible for twisting that magnetic field to drive the sunspot cycle. 08:28: In fact, helioseismic holography is capable of detecting sunspots long before the sun rotates them into visibility.
	2017-12-20: Extinction by Gamma-Ray Burst 00:49: For example, the gradual heating and eventual death of the sun. 02:41: Now, some won't die that way, but any star more than around eight times the Sun's mass will. 04:22: And nitrogen dioxide absorbs visible light, reducing the energy received from the sun. 07:27: The exposed inner star shines several times hotter and hundreds of thousands of times brighter than the Sun. 08:58: However, the Sun isn't stationary. 12:03: Recent studies suggest that there's a 3% chance that the Sun will jump galaxies on Andromeda's first fly by. 08:58: However, the Sun isn't stationary. 05:05: ... by the global cooling triggered by a few years of NO2 absorption of sunlight. ... 06:22: That event may have been the increase in sunlight absorbing NO2 after a GRB. 02:41: Now, some won't die that way, but any star more than around eight times the Sun's mass will.
	2017-12-13: The Origin of 'Oumuamua, Our First Interstellar Visitor 00:29: On October 19th this year, astronomers spotted an unusual object moving rapidly away from the sun. 02:32: Oumuamua doesn't have a tail like a comet, so its surface isn't vaporizing in the sun's radiation. 03:22: Meaning the object is gravitationally bound to the sun. 03:47: And they never actually orbit the sun. 03:49: Rather, they're deflected by the sun's gravity as they pass by. 04:07: Oumuamua had a maximum speed of 87.7 kilometers per second at its closest approach to the sun, which is well inside Mercury's orbit. 04:24: That means Oumuamua has enough speed to climb out of the sun's gravitational well and escape back to interstellar space. 05:25: PZ 17 performed more computer simulations to rewind the motion of both Oumuamua and the 3,700 stars within 100 light years of the sun. 06:46: Our sun, as it moves around the galaxy, passes through this field of debris. 02:32: Oumuamua doesn't have a tail like a comet, so its surface isn't vaporizing in the sun's radiation. 03:49: Rather, they're deflected by the sun's gravity as they pass by. 04:24: That means Oumuamua has enough speed to climb out of the sun's gravitational well and escape back to interstellar space. 03:49: Rather, they're deflected by the sun's gravity as they pass by. 02:32: Oumuamua doesn't have a tail like a comet, so its surface isn't vaporizing in the sun's radiation.
	2017-11-22: Suicide Space Robots 08:44: ... solar system in 2012, it passed the heliopause-- the boundary where the sun's magnetic field and solar wind give way to the ambient environment of the ...
	2017-10-25: The Missing Mass Mystery 00:41: When we extrapolate observations to the entire observable universe, we find a billion trillion suns worth of mass. 08:14: The secret is the thermal Sunyaev-Zel'Dovich effect. 09:00: ... just published the results of their attempts to look for the Sunyaev-Zel'Dovich ... 09:44: Both teams report detection of the thermal Sunyaev-Zel'Dovich effect with around 5 sigma significance. 08:14: The secret is the thermal Sunyaev-Zel'Dovich effect. 09:00: ... just published the results of their attempts to look for the Sunyaev-Zel'Dovich Effect. ... 09:44: Both teams report detection of the thermal Sunyaev-Zel'Dovich effect with around 5 sigma significance.
	2017-10-04: When Quasars Collide STJC 01:40: They start with masses of up to 10 or so Suns. 01:44: The ones in the course of galaxies contain the mass of a million two billion Suns. 02:55: Quasar is the term for the most powerful AGNs, and they contain SMBHs with up to billions of Suns in mass. 01:40: They start with masses of up to 10 or so Suns. 01:44: The ones in the course of galaxies contain the mass of a million two billion Suns. 02:55: Quasar is the term for the most powerful AGNs, and they contain SMBHs with up to billions of Suns in mass.
	2017-09-28: Are the Fundamental Constants Changing? 12:50: Mike Williams asks about the possibility of using our sun as a gravitational lensing telescope. 13:17: It would then look back at light lensed in the sun's gravitational field. 13:29: Among the many challenges presented by this idea is that you could really only have a look in one direction back towards the sun. 13:17: It would then look back at light lensed in the sun's gravitational field.
	2017-09-20: The Future of Space Telescopes 01:41: Our sun is about 10 billion times brighter than Earth. 01:44: Train a distant telescope on us, and it would be overwhelmed by the sun's rays. 02:24: ... where near the factor of 10 billion difference between the Earth and the sun. ... 04:01: So one of these things would allow us to see Earth in orbit around the sun from 60-light years away. 04:08: There are a couple of thousand stars within that range, and hundreds of sun-like stars, many of which certainly have Earth-like planets. 01:44: Train a distant telescope on us, and it would be overwhelmed by the sun's rays.
	2017-09-13: Neutron Stars Collide in New LIGO Signal? 02:06: A remnant core between 1.4 and around 3 times the mass of our sun instead ends up as a neutron star. 04:00: See, black holes only form in the deaths of the most massive stars, those over approximately 20 times the Sun's mass.
	2017-08-24: First Detection of Life 07:22: We do it by enjoying lovely exoplanet sunsets.
	2017-08-16: Extraterrestrial Superstorms 04:09: They are most often anti-cyclonic, high-pressure systems and are powered not by the sun, but by the collapse of the planet itself. 04:23: They originally collapsed from the vast gas disk left over after the sun's birth. 01:45: In the case of earth storms, the energy powering that convection comes from the sun-warmed ocean. 03:58: The most powerful storms tend to be low-pressure cyclonic systems powered by sun-warmed water. 01:45: In the case of earth storms, the energy powering that convection comes from the sun-warmed ocean. 03:58: The most powerful storms tend to be low-pressure cyclonic systems powered by sun-warmed water. 01:45: In the case of earth storms, the energy powering that convection comes from the sun-warmed ocean. 03:58: The most powerful storms tend to be low-pressure cyclonic systems powered by sun-warmed water.
	2017-08-02: Dark Flow 02:05: This motion is due to the sun's orbit around the Milky Way and the Milky Way falling to the Great Attractor-- more on that last one soon. 03:27: To explain this, I'll need to tell you about the kinematic Sunyaev-Zeldovich, KSZ, effect. 03:33: And actually, let's just start with the regular old thermal Sunyaev-Zeldovich effect. 04:17: Now, kinematic Sunyaev-Zeldovich effect is much, much harder to see than the thermal SZ effect. 03:33: And actually, let's just start with the regular old thermal Sunyaev-Zeldovich effect. 04:17: Now, kinematic Sunyaev-Zeldovich effect is much, much harder to see than the thermal SZ effect. 03:27: To explain this, I'll need to tell you about the kinematic Sunyaev-Zeldovich, KSZ, effect.
	2017-07-07: Feynman's Infinite Quantum Paths 12:49: And this is a really great way to simultaneously support the show and to not burn your eyes out staring at the sun.
	2017-05-31: The Fate of the First Stars 00:30: [MUSIC PLAYING] The sun is a late-comer to our universe. 00:45: See, the sun and all stars are made of the raw material forged in the heat of the Big Bang itself-- hydrogen and helium, mostly. 00:54: When the sun's light is broken into a spectrum, it reveals traces of many of the heavier elements of the periodic table. 01:01: ... spread their element-enriched guts through the galaxy, long before the sun was even a twinkle in the eye of a giant molecular ... 01:47: The sun is a population one star, meaning 2% to 3% of its mass is metals. 03:17: Even stars a little smaller than our sun-- the orangish K-type stars-- live for longer than the current age of the universe. 03:31: But stars of the sun's mass and higher that formed over 13 billion years ago, near the beginning of the universe, would now be long gone. 04:34: So the cores of very massive stars are much hotter than our suns-- up to a couple hundred million Kelvin, versus the sun's 15 million K. 04:58: A star 10 times the mass of the sun shines around 10,000 times brighter. 05:04: Now, burning through 10 times the fuel at 10,000 times the rate, compared to the sun, means its life is 1,000 times shorter-- only 10 million years. 05:15: ... three stars would have had masses of at least several times that of the sun, while the largest would have been as much as 1,000 or more times the ... 09:15: ... black holes, with millions to billions of times the mass of the sun, that we find lurking in the centers of ... 04:58: A star 10 times the mass of the sun shines around 10,000 times brighter. 00:54: When the sun's light is broken into a spectrum, it reveals traces of many of the heavier elements of the periodic table. 03:31: But stars of the sun's mass and higher that formed over 13 billion years ago, near the beginning of the universe, would now be long gone. 04:34: So the cores of very massive stars are much hotter than our suns-- up to a couple hundred million Kelvin, versus the sun's 15 million K. 05:15: ... while the largest would have been as much as 1,000 or more times the Sun's ... 04:34: So the cores of very massive stars are much hotter than our suns-- up to a couple hundred million Kelvin, versus the sun's 15 million K. 00:54: When the sun's light is broken into a spectrum, it reveals traces of many of the heavier elements of the periodic table. 03:31: But stars of the sun's mass and higher that formed over 13 billion years ago, near the beginning of the universe, would now be long gone. 05:15: ... while the largest would have been as much as 1,000 or more times the Sun's mass. ...
	2017-05-17: Martian Evolution 13:15: ... offset in the positions of stars around the limb, the edge, of the sun due to the powers of their light bending in the suns gravitational ... 13:40: ... need to compare the positions of stars on either side of the sun during the eclipse and then several months later when the sun has moved ... 14:29: And it's also the sun's angular diameter. 14:31: So it takes one hour for the moon to fully eclipse the sun and another hour to move past it. 06:49: ... the other hand, the less intense sunlight at Mars compared to Earth means it'll be harder to produce vitamin D. ... 13:15: ... the edge, of the sun due to the powers of their light bending in the suns gravitational ... 14:29: And it's also the sun's angular diameter. 13:15: ... the edge, of the sun due to the powers of their light bending in the suns gravitational ...
	2017-05-10: The Great American Eclipse 00:08: ... to raise your hands to the heavens and threaten to block out the sun. ... 01:00: ... moon has to be on the opposite side of the Earth compared to the sun to catch the Earth's shadow and so lunar eclipses are always during full ... 01:08: And the moon has to be between the sun and the Earth for its shadow to hit us. 01:26: The moon's orbit about the Earth and the Earth's orbit about the sun, the ecliptic plane, are misaligned by about 5 degrees. 01:58: It'll be partial because the Earth won't completely covered the sun from the moon's perspective. 02:23: So that's the penumbra of the moon's shadow, where the sun isn't completely blocked. 03:01: In fact, the spaces between the leaves act like pinhole cameras, projecting the sun's image to the ground. 03:20: But whatever you do, don't look directly at the sun, at least not yet. 03:32: You need aluminized mylar or number 14 welder's glass, something approved specifically for viewing the sun. 03:42: Over the course of the next hour, the moon eats further and further into the sun. 03:53: The moon is much smaller, but much closer than the sun. 04:01: This August, the moon will span 0.538 degrees, just big enough to completely obscure our 0.527 degrees sun. 04:12: The moon's orbit is elliptical, and so sometimes it eclipses the sun when it's a bit further away from the Earth. 04:19: It appears smaller to us and so doesn't completely block the sun. 04:48: And so in the future, it won't be able to block out the entire sun anymore. 05:16: With your glasses on, you see the sun is a mere sliver, and it's shrinking. 05:36: But now it's the last thin sliver of the sun that's twinkling. 05:43: The sun's final crescent contracts to a last spark on one side of the moon, like a diamond ring. 05:54: It's the one time you can stare safely straight towards the sun. 05:58: ... red from a specific electron transition in the hydrogen of the sun's upper ... 06:18: What shows up next is the ghostly light of the corona, the sun's outermost atmosphere. 06:24: The corona is always there, but its faint glow is normally overwhelmed by the glare of the sun's surface. 06:30: Right next to the black sun, you'll see the bright star Regulus and its constellation, Leo. 06:41: Mercury orbits so close to the sun that it's hard to catch in a dark enough sky. 02:23: So that's the penumbra of the moon's shadow, where the sun isn't completely blocked. 06:30: Right next to the black sun, you'll see the bright star Regulus and its constellation, Leo. 03:28: So no joke here-- you need these, and sunglasses won't cut it. 04:23: Such eclipses are called annular eclipses, because they leave a ring of bright sunlight around the moon's disk. 06:12: Really, they're extra sunlight peeking through lunar valleys. 02:38: At first, you won't notice much change in the glorious sunny day, fingers crossed for the weather. 03:01: In fact, the spaces between the leaves act like pinhole cameras, projecting the sun's image to the ground. 05:43: The sun's final crescent contracts to a last spark on one side of the moon, like a diamond ring. 05:58: ... red from a specific electron transition in the hydrogen of the sun's upper ... 06:18: What shows up next is the ghostly light of the corona, the sun's outermost atmosphere. 06:24: The corona is always there, but its faint glow is normally overwhelmed by the glare of the sun's surface. 05:43: The sun's final crescent contracts to a last spark on one side of the moon, like a diamond ring. 03:01: In fact, the spaces between the leaves act like pinhole cameras, projecting the sun's image to the ground. 06:18: What shows up next is the ghostly light of the corona, the sun's outermost atmosphere. 06:24: The corona is always there, but its faint glow is normally overwhelmed by the glare of the sun's surface. 05:58: ... red from a specific electron transition in the hydrogen of the sun's upper ...
	2017-04-05: Telescopes on the Moon 04:23: When exposed to the sun, temperatures rise to around 125 Celsius, well, above the boiling point of water. 01:34: And three, on earth, sunlight is scattered to make our blue sky. 05:17: Hit by sunlight, tiny regolith particles build up electric charge, and so repel each other into dust fountains in the low lunar gravity. 04:37: ... Yutu was experiencing a massive temperature differential between its sunny side and shaded ...
	2017-03-15: Time Crystals! 02:49: Cups of coffee cool down, planets orbit the sun, the universe expands. 11:54: Yet it's estimated that a system with an Earth-like planet orbiting a Sun-like star has around a 1% chance of transiting from our perspective.
	2017-03-01: The Treasures of Trappist-1 01:11: The star, TRAPPIST-1a, is an ultra cool dwarf star, about 10% the sun's diameter and less than 10% its mass. 01:20: It's also much colder, about 2,500 Kelvin compared to the sun's 5800 Kelvin. 04:39: That could be OK for habitability if they have sufficiently thick atmospheres to mix the heat from their sun globally. 05:24: For comparison, our sun and moon span around half a degree on the sky. 05:29: On the inner planets' sunny side, the star will provide about as much visible light as our sun. 05:53: Out here on Earth, our distance and our magnetosphere protect us from most of the sun's coronal mass ejections. 06:12: The TRAPPIST-1a's winds may have eroded its planet's atmospheres, just as the sun did with Mars. 04:39: That could be OK for habitability if they have sufficiently thick atmospheres to mix the heat from their sun globally. 05:29: On the inner planets' sunny side, the star will provide about as much visible light as our sun. 04:20: It would look pink on the sky to us, but there will be no day and night so an eternal sunrise. 01:11: The star, TRAPPIST-1a, is an ultra cool dwarf star, about 10% the sun's diameter and less than 10% its mass. 01:20: It's also much colder, about 2,500 Kelvin compared to the sun's 5800 Kelvin. 05:53: Out here on Earth, our distance and our magnetosphere protect us from most of the sun's coronal mass ejections. 01:20: It's also much colder, about 2,500 Kelvin compared to the sun's 5800 Kelvin. 05:53: Out here on Earth, our distance and our magnetosphere protect us from most of the sun's coronal mass ejections. 01:11: The star, TRAPPIST-1a, is an ultra cool dwarf star, about 10% the sun's diameter and less than 10% its mass.
	2017-02-22: The Eye of Sauron Reveals a Forming Solar System! 00:44: Fomalhaut is an A-type star about twice as massive and much hotter and brighter than the sun. 04:16: This is believed to have happened some tens of millions of years after the sun first formed. 08:44: For example, our sun has long since left its birth siblings behind.
	2017-02-15: Telescopes of Tomorrow 01:16: Webb will begin unfolding its 18 hexagonal mirrors on its journey to the sun-earth system's second Lagrange point about a million miles away. 04:19: It also sports a 5-layer sun-shield to block as much sunlight as possible.
	2017-02-02: The Geometry of Causality 14:54: ... first generation of stars, perhaps thousands of times the mass of the sun. ... 15:05: But by now, some of those have grown to billions of times the mass of the sun.
	2017-01-25: Why Quasars are so Awesome 01:05: They have a supermassive black hole, millions to billions of times the mass of the sun. 03:59: Take a black hole of millions to billions of times the mass of the sun.
	2017-01-11: The EM Drive: Fact or Fantasy? 11:09: SunPower Guru argues that SITI is pointless, because there's no good reason to think that aliens would use, for example, radio.
	2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer 01:43: At around 15 times the mass of the sun, the dark object in this system can't be anything but a black hole. 05:12: It has enough energy to produce a black hole with a mass of 100,000 suns and an event horizon that almost reaches the moon's orbit. 09:23: The Dyson sphere absorbs all of the energy from the shell, so it immediately gains the entire mass equivalence, 100,000 suns worth. 09:53: ... the original mass of the sphere isn't going to add enough to the 100,000 suns of the near Kugelblitz to appreciably increase the size of the event ... 10:41: ... there's the slight problem of having blocked out the sun, but hey, we just built an infinitely strong Dyson sphere and charged it ... 10:53: Maybe we can just build a mini sun inside after we blast the aliens and save spacetime. 05:12: It has enough energy to produce a black hole with a mass of 100,000 suns and an event horizon that almost reaches the moon's orbit. 09:23: The Dyson sphere absorbs all of the energy from the shell, so it immediately gains the entire mass equivalence, 100,000 suns worth. 09:53: ... the original mass of the sphere isn't going to add enough to the 100,000 suns of the near Kugelblitz to appreciably increase the size of the event ... 09:23: The Dyson sphere absorbs all of the energy from the shell, so it immediately gains the entire mass equivalence, 100,000 suns worth.
	2016-12-14: Escape The Kugelblitz Challenge 04:47: This blast has a mass-energy equivalence of 100,000 suns.
	2016-11-02: Quantum Vortices and Superconductivity + Drake Equation Challenge Answers 04:46: For 100 light years, we have 512 G-Type stars: that's the same type as our sun. 05:05: So that means there are around 100 such planets orbiting stars like the sun within 100 light years. 07:21: ... we instead need to ask, "How large a sphere centered on the sun would also contain 100,000 stars?" There should be, on average, around ...
	2016-10-19: The First Humans on Mars 09:52: A star's core needs to be more massive than around three times the mass of the sun in order to collapse into a black hole.
	2016-10-12: Black Holes from the Dawn of Time 03:39: PBHs could have been formed at a few grams to tens of thousands of times the mass of the sun, depending on which formation model you go with. 06:17: ... or a much smaller number of really big PBHs around 20 to 100 times the Sun's ... 08:07: Even a close encounter with a black hole as massive as the Sun or higher would be pretty catastrophic. 03:39: PBHs could have been formed at a few grams to tens of thousands of times the mass of the sun, depending on which formation model you go with. 13:21: ... the hordes of octopodes rise from sunken R'lyeh to harken his coming, these silly grammatical quibbles will seem ... 06:17: ... or a much smaller number of really big PBHs around 20 to 100 times the Sun's ...
	2016-10-05: Are We Alone? Galactic Civilization Challenge 02:43: Around 11 billion of those are Earth-like planets around Sun-like stars.
	2016-09-29: Life on Europa? 07:05: Ultimately, their energy and nutrients come from sunlight-powered microorganisms, like algae and plankton, at the ocean's surface.
	2016-09-14: Self-Replicating Robots and Galactic Domination 10:44: In a recent episode, we asked whether it's even possible, or a good idea, to build a Dyson swarm to capture all of our sun's energy. 11:14: However, it is conceivable that you could cause the solar collectors to fill up as they transited the sun, leaving a gap for sunlight. 11:01: Well, a full Dyson swarm interior to Earth's orbit would, indeed, block sunlight and freeze our planet. 11:14: However, it is conceivable that you could cause the solar collectors to fill up as they transited the sun, leaving a gap for sunlight. 10:44: In a recent episode, we asked whether it's even possible, or a good idea, to build a Dyson swarm to capture all of our sun's energy.
	2016-08-24: Should We Build a Dyson Sphere? 02:09: The sphere would not be habitable, having only a tiny gravitational pull at its surface, and that would be towards the sun. 02:20: Any small bump would cause one side to fall into the sun. 02:49: ... in diameter and each with its own independent stable orbit around the sun. ... 03:03: Build enough of these, and you can read the entire sun in all directions, absorbing its entire energy output. 05:16: ... fully encompass the sun, we'd probably need to devour Venus, Mars, and a good number of asteroids ... 06:06: Once complete, the Dyson swarm would harvest a good fraction of the sun's energy, so trillions of times the current energy output of the planet. 06:31: The advantage of using sunlight is that the sun is already making it. 06:39: Only 0.7% of the rest mass of the ingoing hydrogen fuel at the sun's core is converted to energy. 08:07: And we only need 1 billion Kugelblitzes to equal the sun's output. 08:30: The Dyson sphere/swarm can absorb at most the entire energy output of the sun. 08:50: ... 600 million kilogram Kugelblitz, it takes something like 10% of the sun's energy output each second, focused into a single attometer at a single ... 06:31: The advantage of using sunlight is that the sun is already making it. 06:06: Once complete, the Dyson swarm would harvest a good fraction of the sun's energy, so trillions of times the current energy output of the planet. 06:39: Only 0.7% of the rest mass of the ingoing hydrogen fuel at the sun's core is converted to energy. 08:07: And we only need 1 billion Kugelblitzes to equal the sun's output. 08:50: ... 600 million kilogram Kugelblitz, it takes something like 10% of the sun's energy output each second, focused into a single attometer at a single ... 06:39: Only 0.7% of the rest mass of the ingoing hydrogen fuel at the sun's core is converted to energy. 06:06: Once complete, the Dyson swarm would harvest a good fraction of the sun's energy, so trillions of times the current energy output of the planet. 08:50: ... 600 million kilogram Kugelblitz, it takes something like 10% of the sun's energy output each second, focused into a single attometer at a single ... 08:07: And we only need 1 billion Kugelblitzes to equal the sun's output.
	2016-08-10: How the Quantum Eraser Rewrites the Past 11:08: And they're at least several times the mass of the sun. 12:25: The increasing temperature of the sun will cause all of Earth's oceans to evaporate in a billion years, plus or minus, depending on the model. 12:48: As for the death of the sun and Andromeda's collision with the Milky Way, OK.
	2016-08-03: Can We Survive the Destruction of the Earth? ft. Neal Stephenson 08:25: A supernova explosion within 30 light years would destroy the ozone layer, leading to a horrible hard ultraviolet bath and the worst sunburn ever.
	2016-07-27: The Quantum Experiment that Broke Reality 11:18: ... a star?" Well, the lowest mass stars are around 7.5% the mass of the Sun, while Jupiter is 1/10,000 of a solar ... 11:45: Well, the Sun and other stars don't need rocky cores because they are massive enough for all of that gas to collapse by itself. 12:04: For typical interstellar clouds, the Jeans mass is quite a bit smaller than the Sun's mass but still much, much larger than Jupiter's.
	2016-07-20: The Future of Gravitational Waves 00:43: These oscillations echoed the final 1/10 of a second of the end spiral and merger of a pair of black holes, each around 30 times the mass of the Sun.
	2016-07-06: Juno to Reveal Jupiter's Violent Past 00:32: It's by far the largest and most massive thing in our solar system after the sun. 00:37: It may only have 1,000th of the sun's mass, but it weighs more than all the other planets combined, two and 1/2 times more. 01:11: It likely grew as fragments of rock and ice clung to each other in the disk of debris and gas surrounding the infant sun, the protoplanetary disk. 02:15: That's 5.2 times Earth's average distance from the sun. 02:49: Even the sun feels Jupiter's tug. 02:51: The center of mass of the sun-Jupiter system lies just above the solar surface, and both the sun and Jupiter circle this point. 03:10: I'm talking about the rare long period comets that orbit the sun with periods of hundreds to many thousands of years. 05:13: In this model, Jupiter first formed closer to the sun at around 3.5 astronomical units. 06:56: ... the inner solar system would have sent such planets spiraling into the sun, leaving only a limited amount of material to then build the current crop ... 10:38: So many of you, including Neil deGrasse Tyson, point out that the sun is actually white and not yellow. 10:46: ... the sun usually appears white to our eyes and so to our brains, and since the ... 11:05: The sun does emit a bit more light in the yellowy green part of the electromagnetic spectrum compared to the blue and the red parts on either side. 11:19: A more color sensitive eye or electronic detector would see the sun as yellowish green. 02:49: Even the sun feels Jupiter's tug. 06:56: ... the inner solar system would have sent such planets spiraling into the sun, leaving only a limited amount of material to then build the current crop of ... 02:51: The center of mass of the sun-Jupiter system lies just above the solar surface, and both the sun and Jupiter circle this point. 00:37: It may only have 1,000th of the sun's mass, but it weighs more than all the other planets combined, two and 1/2 times more.
	2016-06-22: Planck's Constant and The Origin of Quantum Mechanics 02:43: For example, along with the sun's temperature, it sets the color of sunlight. 02:49: If the Planck constant were 25% smaller, the sun would be violet, all else being equal. 03:42: The sun is yellow because its 6000 Kelvin surface produces more photons in the green yellow part of the electromagnetic spectrum than anywhere else. 09:10: ... of an object's heat glow, for example, by observing the color of the sun. ... 10:38: ... blackbody spectrum, the Planck constant can be read in the color of the sun and the stars, in the brightness of the different colors of the ... 00:23: In fact, you can see the effect of this quantum behavior and even measure the Planck constant just by observing the color of sunlight. 02:43: For example, along with the sun's temperature, it sets the color of sunlight. 04:13: It was Sir Isaac Newton who first analyzed this heat glow in the 1660s when he used a prism to split sunlight into its component colors. 02:43: For example, along with the sun's temperature, it sets the color of sunlight.
	2016-06-15: The Strange Universe of Gravitational Lensing 02:11: ... catch an eclipse of the sun and to measure the tiny change in the position of nearby stars due to ... 02:28: Their light paths were slightly deflected, making them appear a bit further from the sun. 02:11: ... the position of nearby stars due to the deflection of their light by the sun's gravitational ...
	2016-06-08: New Fundamental Particle Discovered?? + Challenge Winners! 06:01: So it's true that high sunspot activity can increase solar irradiance.
	2016-05-25: Is an Ice Age Coming? 02:07: Earth's motion around the sun changes, and with it, the intensity and distribution of sunlight. 02:46: ... the absolute maximum eccentricity, Earth's most distant point from the sun-- the Aphelion-- is about 30% further than the closest point, the ... 03:10: The Southern Hemisphere is closer to the sun in summer and further in the winter, so more extreme seasons. 03:18: ... in sunlight intensity due to this difference in distance from the sun is much less than the simple difference due to the seasons ... 04:37: Because then the highest latitudes, where glaciation begins, never get much sun. 08:42: First, low obliquity means less overall sun at high latitudes where the glaciers start. 08:49: Second, high eccentricity means one hemisphere experiences a bad winter at Aphelion, further from the sun. 02:07: Earth's motion around the sun changes, and with it, the intensity and distribution of sunlight. 03:18: ... the difference in sunlight intensity due to this difference in distance from the sun is much less ... 08:05: As ice cover increases, Earth starts to reflect more incoming sunlight. 08:13: More ice means less absorbed sunlight, lowering global temperature and allowing even more ice to grow. 03:18: ... the difference in sunlight intensity due to this difference in distance from the sun is much less than the ... 08:13: More ice means less absorbed sunlight, lowering global temperature and allowing even more ice to grow.
	2016-05-04: Will Starshot's Insterstellar Journey Succeed? 01:31: A spacecraft is propelled as the light from the sun-- or from a giant laser-- accelerates a sail of reflective material. 01:57: Light sails need no onboard propellant and the power generation stays back at home, whether it's the sun or an Earth-based laser. 02:35: Well in that case, light from the sun just won't cut it. 02:46: Accelerating on sunlight alone would make it a many millennium mission.
	2016-04-27: What Does Dark Energy Really Do? 03:55: Take a white dwarf, the leftover core of a dead, low-mass star like our sun, and let it cannibalize some of the material from a binary companion.
	2016-04-13: Will the Universe Expand Forever? 11:15: But recent work has suggested that it might actually be formed in lower-mass stars like our sun after they enter the red giant phase. 12:06: The Sun has orbited the Milky Way around 18 times since it formed. 12:21: It collapsed into the Sun's sibling stars, which are also scattered across the galaxy by now.
	2016-04-06: We Are Star Stuff 04:55: Our sun, and in fact every star in the prime of its life on what we call the main sequence, shines by forging hydrogen into helium. 05:05: ... the case of the sun, when that process is finished, it'll puff out to become a red giant ... 05:36: ... the largest stars, any bigger than around eight times the sun's mass, reach the ends of their lives, they become super giants, and their ... 08:47: ... a white dwarf, a remnant of a low mass star like the sun, has a binary partner star and manages to accrete, to steal from it ... 05:36: ... the largest stars, any bigger than around eight times the sun's mass, reach the ends of their lives, they become super giants, and their ...
	2016-03-30: Pulsar Starquakes Make Fast Radio Bursts? + Challenge Winners! 00:59: And that distance measurement allowed scientists to calculate the FRB power output as that of 500 million Suns.
	2016-03-16: Why is the Earth Round and the Milky Way Flat? 07:18: And this hydrostatic equilibrium keeps stars like our sun extremely spherical and happily burning away for billions of years. 07:31: The Earth and the Sun, for that matter, rotate on their axes. 07:18: And this hydrostatic equilibrium keeps stars like our sun extremely spherical and happily burning away for billions of years.
	2016-03-02: What’s Wrong With the Big Bang Theory? 10:51: For example, the solar system is better described with the Schwarzschild metric, dominated by the sun's gravitational field.
	2016-02-17: Planet X Discovered?? + Challenge Winners! 00:48: And presumably is just one of many such rocks orbiting the Sun in the vast Kuiper Belt, out beyond Neptune. 01:31: ... a year-length, of 15,000 Earth years, and an average distance to the Sun of 700 astronomical ...
	2016-02-03: Will Mars or Venus Kill You First? 01:35: ... the solar wind, the constant stream of energetic particles from the sun, to whittle away at Mars' ... 05:27: This is when a magnetic storm on the sun's surface sends out a blast of extremely high energy particles, most notably protons and electrons. 06:06: ... these blasts typically take days to reach Mars from the sun and are preceded by some visible indication like a solar flare, whose ... 08:03: ... the interaction of the sun's magnetic field with Venus's think atmosphere actually induces something ... 05:27: This is when a magnetic storm on the sun's surface sends out a blast of extremely high energy particles, most notably protons and electrons. 08:03: ... the interaction of the sun's magnetic field with Venus's think atmosphere actually induces something ... 05:27: This is when a magnetic storm on the sun's surface sends out a blast of extremely high energy particles, most notably protons and electrons.
	2015-12-16: The Higgs Mechanism Explained 08:42: For the sun, that's 3 kilometers.
	2015-12-09: How to Build a Black Hole 02:17: ... a bowl of neutrons the size of a city, with a mass of at least 1.4 suns and the density of an atomic ... 08:26: It's three times the mass of the sun. 12:08: Max Shifter asked about the plausibility of directing a killer asteroid into the sun. 12:13: So even the largest asteroid hitting the sun would barely make a splash. 12:18: ... problem is that changing its velocity enough to hit the sun, or even to fall into Earth's orbit-- which was another suggestion-- ... 02:17: ... a bowl of neutrons the size of a city, with a mass of at least 1.4 suns and the density of an atomic ...
	2015-11-18: 5 Ways to Stop a Killer Asteroid 03:50: ... raising to launch the Sentinel infrared telescope, that will orbit the sun and look outwards, tracking hundreds of thousands of ... 05:53: The sun's light will push harder on the more reflective side, slowly pushing it just far enough off course to miss us.
	2015-11-05: Why Haven't We Found Alien Life? 00:26: ... Milky Way and probably billions of them are Earth-sized planets around sun-like ... 09:33: ... all of the sun-like stars and Earth-like planets that will ever form over the full past and ... 00:26: ... Milky Way and probably billions of them are Earth-sized planets around sun-like ... 09:33: ... all of the sun-like stars and Earth-like planets that will ever form over the full past and ... 00:26: ... Milky Way and probably billions of them are Earth-sized planets around sun-like stars. ... 09:33: ... all of the sun-like stars and Earth-like planets that will ever form over the full past and future ...
	2015-10-15: 5 REAL Possibilities for Interstellar Travel 02:57: The sun does this pretty well, so let's build an engine that works like a mini star. 06:55: ... the moon and powered by massive Helium 3 reactors or in orbit around the sun powered by vast solar ...
	2015-10-07: The Speed of Light is NOT About Light 06:13: The Earth is whizzing around the sun, the sun around the Milky Way.
	2015-09-30: What Happens At The Edge Of The Universe? 08:03: For example, the predictions GR makes for planetary orbits can give us a mass for the Sun. 08:09: And that mass predicts the deflection angle for light passing the Sun perfectly, that is its gravitational lensing effect.
	2015-08-27: Watch THIS! (New Host + Challenge Winners) 03:19: ... our planetary system, it'll be a white dwarf remnant, and after the sun ejects its outer layers, there's a planetary ...
	2015-08-19: Do Events Inside Black Holes Happen? 04:52: For simplicity of presentation, let's pretend that the Sun is a perfect sphere. 05:05: ... if I replace the Sun with a spherical black hole that's around six kilometers across-- and ... 05:19: So as far as Earth is concerned, that black hole generates the same spacetime geometry out here that the Sun does. 05:27: In that respect, the black hole certainly behaves like an object, an object with the Sun's mass. 05:48: A black hole that mimics the Sun has a Schwarzschild radius of 3 kilometers. 06:18: I think this idea of suckage is rooted in a misunderstanding of the region that used to be inside the Sun but is still outside the black hole. 13:33: ... are gravitational effects from the Sun and Moon that do the same thing, but they're highly, highly masked by ... 05:05: ... tell you later how I got that number-- the geodesics beyond where the Sun's edge used to be remain ... 05:27: In that respect, the black hole certainly behaves like an object, an object with the Sun's mass. 05:05: ... tell you later how I got that number-- the geodesics beyond where the Sun's edge used to be remain ... 05:27: In that respect, the black hole certainly behaves like an object, an object with the Sun's mass.
	2015-08-05: What Physics Teachers Get Wrong About Tides! 00:07: So if gravity from the Moon and the Sun is really responsible for tides in the ocean and water is water, then why don't we see tides in lakes? 02:10: Assumption two-- let's ignore the Sun. 02:16: The Sun's effects are going to work analogously, anyway. 07:25: First, the Sun-- its effects on tides are analogous to those of the Moon, but they're only about a third as big. 07:31: The Sun is more massive, yes, but it's also much further away. 07:33: Now, when Earth, the Moon, and the Sun all line up in space, the effects are additive and you get extra-large spring tides. 02:16: The Sun's effects are going to work analogously, anyway.
	2015-07-29: General Relativity & Curved Spacetime Explained! 07:40: So for example, say you stick the energy distribution of the sun into the Einstein equations and turn a crank. 07:46: What comes out is a map of the geodesics in the sun's spacetime neighborhood.
	2015-07-08: The Leap Second Explained 01:34: Thus, 12:00 PM on our clocks is continually getting ahead of when the sun is directly over us. 01:40: ... and we insert leap seconds to force our clocks back into sync with the sun. ...
	2015-06-24: The Calendar, Australia & White Christmas 00:33: Now, from one spring equinox to the next spring equinox, Earth does not actually move a full 360 degrees around the sun. 00:43: That means that one cycle of seasons is completed about 20 minutes earlier than a full 360 around the sun. 00:57: Since Earth's axis is tilted, one half of that bulge is a little closer to the sun than the other half at any given moment. 01:04: So the gravitational pull of the sun is slightly stronger on the slightly closer half, causing a net torque on the Earth like this. 01:29: ... Earth's axis precesses in the opposite sense of Earth's orbit around the sun, so that the equinoxes and solstices backtrack along Earth's ... 02:55: But a full trip around the sun takes around six hours longer than a whole number of days. 05:13: But by then, maybe we won't care about locking things to the sun and the seasons so much. 06:04: ... maybe putting planet-sized geometric objects in orbit around the sun. ... 06:52: He also points out that if we put enough of them around the sun that we could cover viewing angles from most star systems. 02:55: But a full trip around the sun takes around six hours longer than a whole number of days. 00:16: ... degrees, so that different parts of the planet will receive more direct sunlight at different times of ... 00:25: In June, the northern hemisphere gets more direct sunlight, so it's northern summer and southern winter.
	2015-06-17: How to Signal Aliens 02:17: Nowadays, lasers can produce high-power ultra-short pulses that can outshine the sun for less than a nanosecond.
	2015-06-03: Is Gravity An Illusion? 10:42: Earth analogs in Earth-like orbits around Sun-like stars are not going to be visible.
	2015-05-27: Habitable Exoplanets Debunked! 01:29: Plus, if you expand its orbit just a teensy bit, it would be in the sun's habitable zone. 05:34: ... the atmospheres of Earth-sized planets in Earth-like orbits around Sun-like like ... 04:23: ... out the star's light, kind of like putting your hand over your eyes on a sunny day to help see your ... 01:29: Plus, if you expand its orbit just a teensy bit, it would be in the sun's habitable zone.
	2015-05-20: The Real Meaning of E=mc² 03:48: ... yes, since the sun is basically an enormous flashlight, its mass drops just by virtue of ... 03:59: That's just a billionth of a trillionth of the sun's mass, and only 0.07% of the sun's mass over its entire 10 billion year lifespan. 04:06: So does this mean that the sun converts mass to energy? 04:10: All the energy in sunlight came at the expense of other energy, kinetic and potential energy, of the particles that make up the sun. 04:17: ... more kinetic and potential energy contained within the volume of the sun manifesting as part of the sun's ... 04:25: Those 4 billion kilograms that the sun loses every second is really a reduction in the kinetic and potential energies of its constituent particles. 04:06: So does this mean that the sun converts mass to energy? 04:25: Those 4 billion kilograms that the sun loses every second is really a reduction in the kinetic and potential energies of its constituent particles. 04:17: ... more kinetic and potential energy contained within the volume of the sun manifesting as part of the sun's ... 04:10: All the energy in sunlight came at the expense of other energy, kinetic and potential energy, of the particles that make up the sun. 03:59: That's just a billionth of a trillionth of the sun's mass, and only 0.07% of the sun's mass over its entire 10 billion year lifespan. 04:17: ... energy contained within the volume of the sun manifesting as part of the sun's ... 03:59: That's just a billionth of a trillionth of the sun's mass, and only 0.07% of the sun's mass over its entire 10 billion year lifespan. 04:17: ... energy contained within the volume of the sun manifesting as part of the sun's mass. ...
	2015-05-13: 9 NASA Technologies Shaping YOUR Future 00:56: Next problem-- the space station orbits Earth so fast that each new sunrise happens every 90 minutes.
	2015-04-29: What's the Most Realistic Artificial Gravity in Sci-Fi? 05:17: ... in that novel has the same radius as Earth's entire orbit around the sun, around 93 million ... 05:51: To sustain 1 g, the ring would need to complete the equivalent of one Earth orbit around the sun in only nine days.
	2015-04-01: Is the Moon in Majora’s Mask a Black Hole? 05:08: ... theoretical estimates say that you'd still need at least 1/10 of the sun's mass, give or take, to make ...
	2015-03-25: Cosmic Microwave Background Explained 02:09: You, a taco, the sun, everything.
	2015-03-11: What Will Destroy Planet Earth? 02:15: But asteroids orbit the sun about 35 times slower than that. 02:44: Well, Earth and Mars' field gravitational pulls not just from the sun, but also from the other plants-- and from big asteroids too. 03:52: For instance, if Earth enters the sun. 03:56: ... right, in about five billion years, the sun will begin its transition into a red giant-- inflating until it becomes ... 04:21: See, the growing sun will also develop a stronger solar wind that sprays a lot of the sun's material out into space. 04:27: In the process, the sun will lose a lot of mass and a lot of gravitational pull, causing Earth's orbit to actually grow. 04:34: For decades, whether Earth will be swallowed by the sun or not has been too close to call. 04:40: But the best recent simulations show that Earth will end up just inside the sun and fry. 04:21: See, the growing sun will also develop a stronger solar wind that sprays a lot of the sun's material out into space. 00:39: Now if you just want to split Earth in half, you get a bit of a discount-- only 16 million years worth of sunshine.
	2015-03-04: Should We Colonize Venus Instead of Mars? 01:45: It's closer to the sun, which means about four times more available solar power then you have on Mars.
	2015-02-18: Is It Irrational to Believe in Aliens? 03:07: ... to Copernicus, is rooted in the democratic notion that our planet, our Sun, our galaxy, none of them are ...

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