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2022-12-14: How Can Matter Be BOTH Liquid AND Gas?

  • 00:27: ... fact, there are planets in our solar system completely covered with this stuff, and you’ve often been the ...
  • 14:17: But the supercritical layer is an integral part of the structure of the biggest planets in the solar system.

2022-12-08: How Are Quasiparticles Different From Particles?

  • 01:00: In semiconductors that make up transistors, diodes, and solar cells the pushing around of a quasiparticle is equally important.
  • 01:44: ... to a higher energy state - say, by thermal vibrations or in the case of solar cells by a photon, at which point the electron is free to move from atom ...
  • 04:23: And these p-n junctions also drive solar cells, LEDs, and transistors.

2022-11-09: What If Humanity Is Among The First Spacefaring Civilizations?

  • 08:27: This can cause erratic climates and make any potential inhabitants vulnerable to solar flares.

2022-10-26: Why Did Quantum Entanglement Win the Nobel Prize in Physics?

  • 16:01: Let’s start with the solar gravitational lens.
  • 16:44: ... also, it may be possible to  use the solar sails themselves,   the ones that propelled these craft to ...

2022-10-12: The REAL Possibility of Mapping Alien Planets!

  • 00:03: ... turns it into a   gigantic lens. What could such a  solar-system-sized telescope see?   Pretty much anything. But definitely it ...
  • 01:25: ... called.   For some reasons scientists went with  SGLF - solar gravitational lens focal   region - missed opportunity if you ...
  • 06:05: ... in a long train,   each riding on the light of the sun with a solar sail. That second seems the preferred option, and   it’s alway way ...
  • 07:45: ... space agency sent the IKAROS   probe to Venus using a 20 meter solar sail, and plenty more solar sails missions are in the ...
  • 09:31: ... and set their sails   squarely against that intense up-close solar radiation. That propels the craft on a trajectory   that will take them ...
  • 10:07: ... spot is a feat of incredible astro-navigation and maneuvering. The solar   gravitational lens focal range is indeed a range. While a regular ...
  • 15:45: ... cool   after you. Well, assuming that the whole  solar gravitational lens thing pans out,   we’re going to have ...

2022-09-21: Science of the James Webb Telescope Explained!

  • 05:09: ... also let’s us see the atmospheres of planets in other solar systems, which is an important step towards finding other life out there ...

2022-08-17: What If Dark Energy is a New Quantum Field?

  • 03:33: ... where there’s even a smattering of regular matter - like inside our solar system, or even inside our galaxy. But if you include the vast voids ...

2022-06-22: Is Interstellar Travel Impossible?

  • 00:01: But is it so deadly that we’re effectively imprisoned in our solar system forever?
  • 01:39: So today we’re going to explore this question - is humanity doomed to spend the rest of our species’ lifespan huddled in our own solar system?
  • 02:05: ... fastest spacecraft we’ve ever built - that’s the 163 km/s of the Parker solar probe - over 7000 years to reach Proxima, if it were even going in the ...
  • 02:35: ... Starshot program proposes to send a train of tiny craft powered by solar sails, which would be accelerated to 20% light speed by a giant array of ...
  • 05:12: So do we not even make it out of our solar system?
  • 05:18: These sort of micrometeorites are somewhat common within the solar system - leftovers from the formation of the planetary system.
  • 05:31: Fortunately, micrometeoroid abundance drops dramatically as we leave the solar system.
  • 05:35: ... maybe we punch straight up out of the solar system to avoid the much higher density of junk in the ecliptic plane - ...

2022-05-25: The Evolution of the Modern Milky Way Galaxy

  • 11:10: ... passes even happens to line up  with the formation of our sun and solar system   4.5 billion years ago. Now, we’re not saying ...
  • 12:11: ... Way   themselves, the entire stream may be 10 billion  solar masses due to the enormous amount of dark   matter it ...

2022-05-18: What If the Galactic Habitable Zone LIMITS Intelligent Life?

  • 00:00: ... solar system is a tiny bubble of habitability  suspended in a vast ...
  • 02:52: ... of these cultures cast their solar deities  in myths that explained real natural ...
  • 09:08: ... know that having a Jupiter-like  planet or two in the outer solar system   can be useful in protecting the  inner system ...
  • 09:26: ... have led to frequent close encounters between  systems. In our solar system, such encounters   disturb our Oort cloud, sending ...
  • 11:12: ... formation history, our  starting intuition seems right: the Sun and solar   system are NOT special as far as our galaxy goes.  But now that we ...
  • 14:14: ... influence  on humanity. Be sure to watch our   Solar mythology episode, which features a  visit from Matt to explain ...

2022-05-04: Space DOES NOT Expand Everywhere

  • 00:52: ... If space  is expanding everywhere,  is it expanding inside the solar system, inside you? And what does it even mean for space to be ...

2022-03-08: Is the Proxima System Our Best Hope For Another Earth?

  • 02:47: So it was named Proxima Centauri, or just Proxima - our solar system’s true nearest neighbour.

2022-01-19: How To Build The Universe in a Computer

  • 04:26: For simulating a solar system,  this method is pretty reasonable.

2022-01-12: How To Simulate The Universe With DFT

  • 00:10: Would it be: a solar system, a planet, a cat?
  • 01:28: In fact you need more particles than exist in the solar system to store the wavefunction of the electrons in a single iron atom.
  • 04:06: ... grid, you’d need to store more numbers than there are particles in the solar ...
  • 12:33: Without taking, like, the entire age of the universe and a solar-system sized computer.
  • 15:07: The assumption in this calculation is that the black hole came from interstellar space and fell into the solar system.
  • 15:14: The minimum velocity it could have on reaching the Earth is the solar system’s escape velocity at Earth’s orbit, or around 42 km/s.
  • 15:49: Either way, it’ll still have solar system escape velocity after the passage through the earth and we would never see it again.

2021-12-29: How to Find ALIEN Dyson Spheres

  • 00:44: ... current energy needs by covering a tiny fraction of Earth’s surface with solar cells. And we should probably do that by the ...
  • 00:56: Not by covering the entire Earth, but by building solar collectors in space.
  • 01:00: ... - a billion times more than what we’d get just covering the planet in solar ...
  • 01:16: The idea of wrapping the sun in solar collectors is not new.
  • 02:01: ... craft, either in orbit around the star or kiting in place on the solar ...
  • 02:38: Earth’s biosphere is already a pretty good planet-scale solar collector.
  • 02:42: If you were to observe Earth from a distant solar system, you might notice that it looks strangely dark.

2021-12-20: What Happens If A Black Hole Hits Earth?

  • 00:29: ... the chance of one coming close enough to cause serious trouble in our solar system is tiny. However there is one scenario which could allow for ...
  • 04:01: ... that there's probably about 10^18 kilograms of dark matter in the solar system at any given time. If that dark matter is tiny black holes then ...

2021-12-10: 2021 End of Year AMA!

  • 00:02: ... nothing fundamentally stopping us from expanding and becoming into solar species but my my gut instinct is that if it's possible and if the ...

2021-11-17: Are Black Holes Actually Fuzzballs?

  • 15:25: Earnest was also a part of the Apollo XI mission, working in the Air Force in Colorado tracking and predicting solar radiation bursts.

2021-11-10: What If Our Understanding of Gravity Is Wrong?

  • 09:53: ... acted like Newtonian mechanics on solar system scales, like MOND on galactic scales, and like regular general ...

2021-08-03: How An Extreme New Star Could Change All Cosmology

  • 08:05: ... for some time that the absolute maximum mass for a white dwarf is 1.44 solar masses - the Chandrasekhar ...
  • 10:37: ... happen when a stellar remnant exceeds the Chandrasekhar limit of 1.44 solar masses - absolute collapse for massive stellar cores or absolute ...

2021-07-21: How Magnetism Shapes The Universe

  • 03:23: ... some of those field lines connect to this greater magnetic field of the solar system - and even of the ...
  • 03:38: Now I don’t want to spend too much time in the solar system - greater magnetic wonders lie beyond.
  • 04:29: ... reconnect, and in the process spray that magnetic field out into the solar system - carrying high energy particles with ...
  • 04:39: These coronal mass ejections join the solar wind.
  • 04:43: Follow one of these magnetic blasts and you’ll spiral through the solar system on a giangantic magnetic tornado.
  • 05:36: ... IBEX mission, which used a sort of solar wind sonar - it mapped how bursts of solar wind material were reflected ...

2021-06-09: Are We Running Out of Space Above Earth?

  • 04:31: ... the amount of drag can change - in particular, during times of high solar activity when more energy is pumped into the atmosphere, causing it to ...
  • 06:10: During a maximum of solar activity when our atmosphere extends further out, the lowest satellites need to be boosted every 2-3 weeks.

2021-05-11: How To Know If It's Aliens

  • 01:55: ... rather continue with our quest to find evidence of primitive life in our solar system. The Viking mission’s labeled release experiment sure looked like ...
  • 03:08: ... look as some of the other hints in our solar system. Still on Martian life, what ever happened to that supposed ...
  • 06:27: ... example of this is ‘Oumuamua - that weird object that flew through our solar system a few years back. ‘Oumuamua appeared as a very faint, pulsing, ...

2021-04-13: What If Dark Matter Is Just Black Holes?

  • 00:00: ... there are billions of microscopic black holes streaming through the solar system, the planet, even our bodies every ...
  • 09:46: ... galaxy, but there’s an intermediate mass range from tens to thousands of solar masses that could still be abundant throughout the Milky ...
  • 10:01: ... galaxies are so small and dense that even black holes with tens of solar masses should have trickled to the center by now, and in the process ...
  • 10:11: ... than 4% of the dark matter could be black holes of tens to thousands of solar ...

2021-03-16: The NEW Crisis in Cosmology

  • 02:07: ... ladder. First you measure   distances to objects in the solar system - then use those to measure distances to nearby ...

2021-03-09: How Does Gravity Affect Light?

  • 11:35: And Einstein’s deflection angle was famously verified by Sir Arthur Eddington, who voyaged to the west coast of Africa to watch a solar eclipse.

2021-02-17: Gravitational Wave Background Discovered?

  • 00:00: ... waves must also exist waves whose single oscillations span the solar system or even the distance to the nearest stars such gravitational ...

2021-01-12: What Happens During a Quantum Jump?

  • 03:40: ... long dead theory about the motion of the planets in an Earth-centered solar ...

2020-12-15: The Supernova At The End of Time

  • 00:10: ... plural, because many very final-seeming fates await the Earth, then solar system, then galaxy, and ultimately the ...
  • 10:50: ... limit could become unstable if it’s mass is greater than 1.16 solar ...
  • 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.

2020-12-08: Why Do You Remember The Past But Not The Future?

  • 02:40: ... particles of dust from a past supernova found each other in the forming solar system and built up into grains then tiny rocks then a ball of different ...

2020-10-13: Do the Past and Future Exist?

  • 15:19: Or maybe life did only spawn once in our solar system and then spread.

2020-10-05: Venus May Have Life!

  • 00:00: ... you rank the most habitable places in our solar system Venus lands pretty low, with surface temperatures hot enough to ...
  • 01:20: But for the longest time Venus was thought to be among the LEAST habitable places in the solar system.
  • 01:55: To the outer solar system - Mars, Enceladus and Europa in particular, and ultimately to planets around other stars.
  • 04:31: ... - more as a control to help guide their studies of planets beyond our solar system, but not really expecting to see anything so close to ...
  • 12:02: However it may be time to refocus our solar system explorations.
  • 13:33: ... bake a nice apple pie and send to welcome our Venusian neighbors to the solar system - or at least into our awareness of their existence in the solar ...

2020-09-28: Solving Quantum Cryptography

  • 14:52: ... - cosmic necklaces can be locked into the magnetic fields within the solar plasma so they don’t fall apart ...
  • 16:59: No Copernican revolution for them, where they realised they weren’t the center of the solar system after all.

2020-09-21: Could Life Evolve Inside Stars?

  • 00:08: There’s Stanislaw Lem’s sentient ocean in Solaris, or the neutron star civilization made of nuclear matter in Robert L Forward’s Dragon’s Egg.

2020-09-01: How Do We Know What Stars Are Made Of?

  • 01:43: ... the great astrophysicist Sir Arthur Eddington, who recounted his recent solar eclipse expedition in which he verified Einstein’s new general theory of ...

2020-07-28: What is a Theory of Everything: Livestream

  • 00:00: ... in an era when we might not ever be able to build that that you know solar system-sized accelerator or even an accelerator bigger than the you ...

2020-07-20: The Boundary Between Black Holes & Neutron Stars

  • 01:22: Its companion was puny by comparison - a mere 2.6 solar masses.
  • 02:44: ... masses of the merging objects were figured figured out as 23.2 and 2.59 solar masses - and we’ll get back to why those are ...
  • 08:34: We’ve estimated a maximum neutron star mass of between 2.2 to 2.4 solar masses.
  • 08:53: Most pulsars are closer to the minimum neutron star mass of around 1.4 solar masses.
  • 09:06: All of these numbers are quite a bit lower the 2.6 solar masses of this new guy.
  • 10:36: A black hole with 2.6 solar masses is difficult to explain.
  • 11:53: It’s a brand new 2.6 solar mass black hole.
  • 12:11: It should arrive at your doorstep in the next few million years, sadly destroying the solar system in the process.

2020-06-08: Can Viruses Travel Between Planets?

  • 07:51: In fact it would be surprising if there were not quite a lot of viral and other microbial material riding the solar wind into interstellar space.
  • 08:13: This is lithopanspermia, and again - virus-ridden rocks have definitely left the Earth before, and probably impacted other bodies in our solar system.
  • 08:32: ... rocks from worlds beyond our solar system are possible, but those viruses would need to remain viable for ...

2020-05-18: Mapping the Multiverse

  • 15:19: ... solar system is moving at 368 km/s relative to the rest-frame of the cosmic ...

2020-04-28: Space Time Livestream: Ask Matt Anything

  • 00:00: ... we rarely turn it on because it's a little bit scary here we have a solar telescope yes this is a six centimeter aperture solar telescope its ...

2020-04-14: Was the Milky Way a Quasar?

  • 08:42: ... the Fermi Bubbles, Sag A* would have needed to devour - a single 50 solar mass star that happened to wander too ...

2020-04-07: How We Know The Earth Is Ancient

  • 04:32: ... and Galileo that earth was just one planet among several in our solar system. Astronomers now swear by the Copernican principle - Earth is not ...
  • 11:02: ... the Earth - both coallescing after a giant planetary impact in the early solar system. Now the moon is tectonically inactive, so rocks on its surface ...
  • 11:55: ... jibes with our measure for the age of solar system. Nearly 4.6 billion years - we get the same number from ...

2020-02-11: Are Axions Dark Matter?

  • 08:58: ... half of the heavy lifting? Well that's precisely what the CERN Axion Solar Telescope (CAST) in Switzerland does. If axions exist then they should ...

2020-01-20: Solving the Three Body Problem

  • 00:20: ... Given the current positions and velocities of the bodies of the solar system, Newton’s equations could be used in principle be used to ...
  • 04:12: ... example, each planet of our solar system can be thought of as a separate two-body system with the Sun. ...
  • 05:01: ... perfectly. Even the smallest planetary bodies have some mass, and the solar system as a whole has many massive constituents. The Sun, Jupiter and ...

2020-01-13: How To Capture Black Holes

  • 00:00: ... of a quasar, where they merge and grow like some monstrous version of a solar system. This insane hypothesis is getting closer to reality, at least ...

2019-12-17: Do Black Holes Create New Universes?

  • 10:14: So, if this universe is optimized for black hole production then there should be no neutron stars more massive than 2 solar masses.
  • 10:24: Well, the most massive known neutron star is 2.17 solar masses, discovered just this year.

2019-11-18: Can You Observe a Typical Universe?

  • 00:34: ... Copernicus presented his model of the solar system which demoted the Earth from its position at the center of the ...
  • 16:26: ... there would be life on almost every planetary body, even in this solar ...

2019-11-11: Does Life Need a Multiverse to Exist?

  • 14:04: ... is the idea that Jupiter may have wandered into the inner solar system during the solar system's formation, disrupting the planets that ...

2019-11-04: Why We Might Be Alone in the Universe

  • 05:41: We’ll start by comparing planets of our solar system, because our ability to probe extra-solar planets is still in its infancy.
  • 05:48: ... Earth has two qualities not shared by the other rocky planets in our solar system: 1) it has a very dynamic interior and 2) a very large ...
  • 05:59: ... magnetic field that protects Earth from dangerous space radiation and solar ...
  • 09:14: Our solar system has a huge range of planet properties - from the tiny rocky Mercury to the gigantic gaseous Jupiter and Saturn.
  • 09:40: That planet acts like a gigantic gravitational vacuum cleaner, absorbing a lot of the debris left over from the formation of the solar system.

2019-10-07: Black Hole Harmonics

  • 08:43: By analyzing the harmonics, the team calculates the mass of the final black hole as 68.5 solar masses.

2019-09-30: How Many Universes Are There?

  • 16:30: ... whether or not a body clears its orbit depends strongly on where in the solar system it forms - the further out, the more massive a body needs to be ...
  • 17:12: Within our solar system it's clear enough which are planets and which aren't by this definition.
  • 17:33: The word planet is reserved exclusively for the 8 bodies of our solar system.

2019-09-23: Is Pluto a Planet?

  • 02:34: The solar system finally made observational and theoretical sense: there were now 6 planets orbiting the sun in perfect mathematical harmony.
  • 04:29: ... taxonomy had to evolve as our understanding of the solar system grew, and so the term planet was reserved for the now-familiar 8 ...
  • 07:15: Also through the 1990s more and more moving specks were discovered within our solar system, beyond Neptune’s orbit.
  • 08:42: ... definitions, met to finally define what it meant to be a planet in our solar ...
  • 11:57: For example, the moons of Jupiter and Saturn are active worlds that may prove to be the only other homes for life within our solar system.
  • 12:11: ... belt, which is of fundamental importance to our understanding of how our solar system ...
  • 13:14: ... eight solar system bodies currently defined as planets certainly share plenty enough ...
  • 16:47: The magnetic field that it does have comes from the interaction of the solar wind with its super thick atmosphere.
  • 17:41: ... of self replicating robots to capture and toss comets into the inner solar system in order to terraform Mars, suggesting that this could, in some ...

2019-09-16: Could We Terraform Mars?

  • 03:49: Earth’s magnetic field protects us from the solar wind, as we saw in a recent episode.
  • 08:51: ... need to cover much of the surface of Mars in solar cells made from abundant silicon in the crust, or build 10 or so million ...
  • 11:18: To really build an Earth-like atmosphere we have to turn our eyes to the rest of the solar system.
  • 12:59: Mars has an atmosphere – either released from deep in the crust or brought in from the far outer solar system.
  • 18:06: ... out that while Venus lacks an Earth-type intrinsic magnetic field, the solar wind striking its atmosphere creates an induced magnetic field that does ...
  • 18:19: The solar wind partially ionizes Venus's upper atmosphere.

2019-09-03: Is Earth's Magnetic Field Reversing?

  • 01:00: Mars, with its solid core, has no such shield – and so the red planet’s atmosphere was stripped away by the solar wind billions of years ago.
  • 11:54: ... probably we’ll have to get much better at shielding satellites from the solar ...
  • 12:34: For now at least we remain protected from the worst ravages of solar storms, and of our dangerously irradiated space time.

2019-08-12: Exploring Arecibo in VR 180

  • 00:13: ... actually figured out that it's riding a rock hurtling through the vast solar system did it learn mastery over matter and the forces of nature and ...
  • 03:24: ... the receivers In fact Arecibo found the very first planet beyond our solar system and it's been central to the search for extraterrestrial ...

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 of stars of ...

2019-07-15: The Quantum Internet

  • 14:45: KowashiHitori points out that Wind and solar won't build battlemechs... just saying.
  • 14:55: Funnies aside, you can't run an energy-hungry compact vehicle on solar or batteries for very long.

2019-07-01: Thorium and the Future of Nuclear Energy

  • 02:49: ... we need it or can we meet those challenges with renewables like wind and solar? ...

2019-06-06: The Alchemy of Neutron Star Collisions

  • 02:47: ... star collision around 80 million years before the formation of the solar system now it would be fair to ask how on earth anyone could know that ...

2019-05-16: The Cosmic Dark Ages

  • 07:19: ... even billions of times the Sun’s mass – inescapable spheres the size of solar systems. And in the final stage of this feeding frenzy, surrounded by ...

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.
  • 09:37: ... found that monster has a mass over 6 billion solar masses, with an event horizon that's about 1/5 the size of that ring– so ...

2019-04-24: No Dark Matter = Proof of Dark Matter?

  • 00:03: ... gravitation might change between short distances like within the solar system and large distances like entire galaxies and clusters such a ...

2019-04-03: The Edge of an Infinite Universe

  • 17:29: After some millions of years watching the galaxies fall apart, the last phase of the destruction of the solar system would happen pretty fast.

2019-03-28: Could the Universe End by Tearing Apart Every Atom?

  • 09:58: The final deadly stage only happens in the last month or so when the solar system is pulled apart.

2019-03-20: Is Dark Energy Getting Stronger?

  • 12:06: It’s not strong enough to have any effect on the space inside a galaxy, so the Milky Way, and certainly the solar system are safe.

2018-12-06: Did Life on Earth Come from Space?

  • 00:37: ... can be accelerated by their star's own radiation and be ejected from the solar system this is Radio panspermia stars may be constantly spraying their ...

2018-11-21: 'Oumuamua Is Not Aliens

  • 00:15: [MUSIC PLAYING] Last year, a visitor came to our inner solar system.
  • 00:29: ... countless times before, lonely rocks, remnants of the formation of our solar system drifting on their endless orbits around the sun, and faintly ...
  • 01:03: It's the first chunk of interstellar space debris we've ever spotted passing through our solar system.
  • 02:51: But now that Oumuamua is on its way out of the solar system, it's doing something even weirder.
  • 04:45: Now that's exactly what you'd expect for solar radiation pressure.
  • 05:54: Oumuamua appears to be accelerating out of the solar system in a way completely consistent with outgassing except there is no visible outgassing.
  • 09:22: ... finally, perhaps Oumuamua isn't from outside our solar system at all, but rather comes from our own Oort cloud and was socked ...
  • 10:18: Oumuamua was traveling at 26 kilometers per second before it entered our solar system.

2018-11-14: Supersymmetric Particle Found?

  • 03:34: Build an accelerator the size of the planet, the solar system, give up and let theorists just tell their stories?

2018-10-25: Will We Ever Find Alien Life?

  • 01:02: ... their presence; radio transmissions, robotic probes, or star-blotting solar ...
  • 04:14: Thrillingly, one proposed explanation was an alien mega structure, perhaps a vast fleet of solar collectors built by the local inhabitants.
  • 04:46: For example, these alien solar collectors may be our best shot at spotting other civilizations.
  • 04:52: An advance civilization may launch so many solar satellites that they substantially block the light from their own star.
  • 05:00: Let's call such a solar fleet a Dyson swarm after the Dyson sphere, which is the next level up, a structure that completely encases a star.

2018-10-10: Computing a Universe Simulation

  • 09:03: Instead of using the mass of the universe to figure out the computation speed, we only have 30 solar masses.

2018-10-03: How to Detect Extra Dimensions

  • 07:48: In our hypothetical universe with four spatial dimensions, gravity is already weak on the scale of the solar system and the galaxy.

2018-08-30: Is There Life on Mars?

  • 09:21: Both rovers were supposed to shut down after around 90 days as Martian dust accumulated on their solar panels, cutting off their power supply.

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.
  • 14:36: ... material surrounding the sun, can be so hot compared to the 5800 Kelvin solar ...
  • 14:53: Just radiating it from the solar surface would lead to temperatures below 5800 Kelvin.

2018-08-01: How Close To The Sun Can Humanity Get?

  • 00:15: ... touching the sun than we ever have before, with the launch of the Parker Solar ...
  • 00:26: ... NASA put humans on the moon, sent probes throughout and even beyond the solar system, and drove a minivan-size Rover across the surface of ...
  • 00:41: And now, NASA will once again attempt the impossible-- reaching for the one place in the solar system we never did approach.
  • 00:49: The Parker Solar Probe will fly within a hair's breadth of the sun itself.
  • 01:20: It also bursts from the solar surface.
  • 01:28: The solar wind, whose origin we see as the solar corona.
  • 01:37: It's visible to the naked eye only during a total solar eclipse.
  • 02:04: Tech that can be damaged or destroyed by solar activity.
  • 03:21: So why do we need the Parker Solar Probe?
  • 03:24: Well, because it won't just watch from a distance, it'll get close enough to bathe in the source of the solar wind.
  • 03:31: ... primary science objective of the Parker Solar Probe-- as stated by NASA-- is to trace the flow of energy and ...
  • 03:40: And to explore what accelerates the solar wind.
  • 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.
  • 04:08: Finally, it will detect radio waves from processes responsible for the acceleration of particles in the solar wind.
  • 04:18: The solar wind electrons, alphas, and protons instrument-- or SWEAP-- will directly detect the particles that make up most of the solar wind.
  • 04:38: It will follow the flow of energy from the solar corona into the accelerating solar wind and connect the solar wind to its source.
  • 04:51: ... will capture the most energetic particles of the solar wind-- charged particles like electrons, protons, and heavier nuclei, ...
  • 05:02: And finally, there's the wide-field imager for Solar Probe or WISPR.
  • 05:10: This set of two telescopes will actually produce images of the solar corona and surroundings.
  • 05:15: From that close up, it'll achieve unprecedented resolution of the solar wind, including shocks and other interesting structures.
  • 05:22: ... which 3D models of the corona can be made, pinpointing the source of solar ...
  • 05:54: ... need to withstand continuous exposure over many orbits to solar radiation and intense temperatures, upwards of 1,650 Kelvin, while ...
  • 06:23: The sun's the biggest object in the solar system and has the strongest source of gravity.
  • 08:20: It'll gather the data we need to understand the corona and the perilous solar wind.
  • 08:26: Humanity has been planning a solar probe since: the late '50s.

2018-06-27: How Asteroid Mining Will Save Earth

  • 01:55: Asteroids, along with comets, are leftover material from the formation of the solar system.
  • 02:09: ... groups of asteroids inhabiting different regions and orbits in the inner solar system, including some that cross Earth's ...
  • 02:20: Unlike the more-icy comets of the outer solar system, asteroids are rocky or metallic.

2018-05-23: Why Quantum Information is Never Destroyed

  • 11:49: Pepsi could extract some free energy if you could build a device that spans several million light years or, I don't know, install some solar panels.

2018-05-16: Noether's Theorem and The Symmetries of Reality

  • 11:05: ... will find more small solar system objects, detect the effects of weak gravitational lensing in ...

2018-05-09: How Gaia Changed Astronomy Forever

  • 06:20: We can potentially, trace the origins of these stars, allowing us to find solar systems that came from the same stellar nurseries.
  • 07:38: It's tracked over 14,000 asteroids and other solar system objects, and found many new ones.

2018-05-02: The Star at the End of Time

  • 00:40: We seek refuge in the outer solar system as the Sun finally expands into a red giant twice.
  • 08:15: Those stars will have long-frozen worlds in the outer parts of their solar systems.

2018-04-25: Black Hole Swarms

  • 07:42: If the sun was near the galactic core, the nearest black hole would be inside the solar systems Oort cloud.

2018-04-18: Using Stars to See Gravitational Waves

  • 01:04: And in the other cases, they were 30 plus solar masses.
  • 02:27: That could make a binary merger in the 5 to 15 solar mass range look like a much more massive merger.
  • 03:49: ... catch the merger of the million to billion solar mass black holes, supermassive black holes that live in the centers of ...

2018-03-28: The Andromeda-Milky Way Collision

  • 00:03: ... four billion years, anyone left in our solar system will witness the most spectacular event to take place in the ...
  • 00:14: But will that be the very last night sky our solar system witnesses?
  • 01:21: But what about the sun, the solar system, the Earth?
  • 07:56: And that could slingshot our solar system into intergalactic space.

2018-03-07: Should Space be Privatized?

  • 05:14: We've sent probes to every planet in our solar system and landed on several, but not a single CEO got rich doing it.

2018-02-21: The Death of the Sun

  • 05:48: It's been blasting its own mess into the solar system in great winds through both red giant phases.
  • 08:16: If we're still solar system bound, then its outer reaches may harbor us for a little while.
  • 08:22: The habitable zone, the region with the right solar flux liquid water, will expand beyond Neptune's orbit in the first red giant phase.

2018-02-14: What is Energy?

  • 12:58: ... is a lot a planet for a star to consume, at least compared to our solar system, which only has little over two Earth masses in the solar ...
  • 13:10: In fact, it may be that our solar system is unusual in this case.
  • 13:27: So what happened to our solar system?
  • 13:30: Well, solar system formation models do indicate a scenario in which our sun may have swallowed some early terrestrial planets.

2018-01-31: Kronos: Devourer Of Worlds

  • 03:10: ... two light-years apart from each other, about 326 light-years from our solar ...
  • 05:36: This is the first stuff to come together in the early days of an inner solar system as things are cooling down.
  • 05:45: ... they condense at core temperatures, they remain vaporized in the inner solar system, but come together further out, giving us gas giants and comets ...
  • 07:19: We talk a bit about the effects of Jupiter on our own solar system in this episode.
  • 08:08: ... a few ways to do this, but most ideas involve increasing the rate of the solar wind while also magnetically driving the outflow towards the poles so ...
  • 08:28: Andrew Milo recommends we block out some of the sun's light with orbiting solar farms.
  • 09:22: ... per several thousand years should be enough to maintain the current solar flux by increasing the size of our ...

2018-01-24: The End of the Habitable Zone

  • 04:55: About them oceans, currently Earth is comfortably inside the solar system's Goldilocks or habitable zone.
  • 05:06: The brightening of the sun means the habitable zone has shifted outwards since the formation of the solar system.
  • 06:54: This is happening already but will massively increase as solar radiation rises.

2018-01-10: What Do Stars Sound Like?

  • 08:05: For example, we can map the currents of plasma and density fluctuations as they shift beneath the solar surface.
  • 08:37: And this can give us advance warning of potentially dangerous solar activity.
  • 11:53: ... that jet would have diverged to something like 10 times the size of our solar system by the time it reaches ...
  • 12:05: It would hit the whole solar system equally.

2017-12-20: Extinction by Gamma-Ray Burst

  • 04:14: Nitric oxide catalyzes the destruction of ozone molecules, depleting the ozone layer that protects us from solar UV.
  • 08:03: Well, no need to pack up and leave the solar system just yet.
  • 09:27: And anyway, there's nowhere in the solar system to hide.
  • 10:37: Last week, we talked about our first detection of a visitor from outside our solar system.
  • 11:14: It was moving much faster than most solar system objects, at around 50 kilometers per second, at its closest approach to Earth.

2017-12-13: The Origin of 'Oumuamua, Our First Interstellar Visitor

  • 00:07: We are currently being visited by a traveler from outside our solar system.
  • 00:51: ... looking at the first object ever observed that came from outside our solar ...
  • 02:25: We've seen such tumblers in our solar system.
  • 03:00: ... observed asteroid-- indeed, every previously observed everything in our solar system-- moves in elliptical orbits as governed by Kepler's ...
  • 03:52: Oumuamua has an eccentricity of 1.2, meaning its hyperbolic path will take it out of the solar system.
  • 05:09: The simplest explanation for Oumuamua's solar system escaping speed is that it gained that speed by falling into the solar system from outside.
  • 05:57: So Oumuamua was probably only a visitor to that solar system too.
  • 06:02: Unless of course there are aliens in that solar system throwing rocks at us?
  • 07:23: ... there must be roughly 700 trillion objects per cubic parsec in the solar ...
  • 07:39: And based on this, PZ 17 predicts that two to 12 of these interstellar objects should pass through our solar system inside Earth's orbit every year.
  • 08:44: Well, it'll leave our solar system behind in roughly 20,000 years.

2017-11-29: Citizen Science + Zero-Point Challenge Answer

  • 03:53: ... signals in LIGO and finding planets forming in the debris disks of new solar ...

2017-11-22: Suicide Space Robots

  • 00:56: Or in the case of the recent destruction of Cassini, to protect the solar system for future experiments.
  • 03:17: Their designers knew that the solar panels would soon be covered by Martian dust, drastically limiting their lifespan.
  • 03:42: NASA's scientists soon realized that the dust was being cleaned from the solar panels by the Martian wind.
  • 06:42: Some of the most mysterious entities in our solar system are the comets that dwell in the Kuiper Belt far outside our planetary system.
  • 06:50: These small icy bodies are thought to carry many secrets of our solar system's formation.
  • 08:00: This caused it to bounce into a region too shaded for its solar powered operation.
  • 08:28: But the same can't be said of the probes we sent to the outer reaches of our solar system.
  • 08:44: ... 35 years exploring our solar system in 2012, it passed the heliopause-- the boundary where the sun's ...

2017-10-25: The Missing Mass Mystery

  • 10:51: The stuff of countless future solar systems is still riding the cosmic web, falling in from the darkest reaches of space time.

2017-10-04: When Quasars Collide STJC

  • 01:49: The largest have event horizons that would envelop most of our solar system.
  • 03:03: But lower down the power scale, we have Seyfert galaxies, which typically contain a single SMBH weighing in at millions of solar masses.

2017-09-28: Are the Fundamental Constants Changing?

  • 13:10: It would send a spacecraft to at least 550 times the Earth's orbital radius, out beyond the edge of the solar system.

2017-09-13: Neutron Stars Collide in New LIGO Signal?

  • 04:12: Neutron stars form from the not quite as rare stars of around 8 to 20 solar masses.
  • 04:32: The remnant core of a dead star must be less than 3 solar masses to make a neutron star.
  • 04:39: But that's a factor of 10 smaller than the 30 solar mass black holes that merged in the first LIGO detection.

2017-08-24: First Detection of Life

  • 01:14: ... before our technology would allow a similar experiment beyond our solar ...
  • 04:15: It's destroyed by solar ultraviolet light in the atmosphere with a half-life of around 50 years.
  • 06:56: We are still a long way from sending a probe like Galileo to another solar system, but we're working on it.

2017-08-16: Extraterrestrial Superstorms

  • 00:34: ... largest and oldest storm in the solar system is Jupiter's Great Red Spot, stretching an incredible two to ...
  • 04:37: As they contract, gas giants convert gravitational potential energy into heat, which in turn powers the largest storms in the solar system.
  • 10:40: And with the help from citizen scientists, perhaps like you, we're sure to unravel some of the secrets of the solar system's most powerful storms.
  • 13:53: Don Solaris asks how I manage to make my beard super-symmetrical.

2017-07-19: The Real Star Wars

  • 09:31: ... fighter launched a specialized missile that destroyed Solwind, a retired solar observatory ...
  • 14:17: ... their eyes burned out by accidentally looking at the August 21st total solar eclipse, we made some Space-Time eclipse ...

2017-07-07: Feynman's Infinite Quantum Paths

  • 12:06: On August 21, for the first time in 40 years, the United States will experience a total solar eclipse.

2017-06-21: Anti-Matter and Quantum Relativity

  • 12:00: My new plan is to level up my skill in time for the solar eclipse in August.

2017-05-31: The Fate of the First Stars

  • 05:26: By comparison, the most massive lighter stars are, at most, a couple of hundred solar masses.
  • 08:57: In fact, it may be that stars greater than around 250 solar masses can collapse directly into a black hole without exploding.
  • 09:04: ... in turn, would merge into monsters of thousands or tens of thousands of solar ...

2017-05-17: Martian Evolution

  • 07:15: Even more dangerous than the UV are high-energy cosmic rays and solar particles.

2017-05-10: The Great American Eclipse

  • 00:30: Yep, the US is going to witness its first total solar eclipse in 40 years.
  • 00:41: Solar eclipses are rare and special events.
  • 00:56: A solar eclipse is when the moon's shadow falls on the Earth.
  • 01:13: So solar eclipses are always during new moons.
  • 01:18: Why the 40 year wait for an American solar eclipse?
  • 01:43: That alignment happens about twice a year and usually results in one solar eclipse and one lunar eclipse.
  • 01:52: The solar eclipse on August 21st will be preceded by a partial lunar eclipse on August 7th.
  • 02:07: However, to see the solar eclipse, you need to be in the narrow path of the moon's shadow.
  • 04:32: But August will give us a total solar eclipse, and those are incomparable.
  • 04:54: In fact, in only half a billion years, the Earth will have its final total solar eclipse.
  • 08:36: Look, I can describe a solar eclipse to you, but you really have to see one for yourself.
  • 08:44: I saw my first solar eclipse on Flinders Island off the south coast of Australia when I was a kid, and it really enhanced my love of astronomy.

2017-04-19: The Oh My God Particle

  • 09:00: Along with solar outbursts, cosmic rays are one of the most serious obstacles to manned interplanetary travel.

2017-04-05: Telescopes on the Moon

  • 05:26: They stick to electronics, impede solar panel function, and grind away at moving parts, nasty stuff.

2017-03-15: Time Crystals!

  • 12:03: ... who pointed out that we basically just learned all about a solar system light years away by studying how faint shadows make other faint ...

2017-03-01: The Treasures of Trappist-1

  • 03:08: Our solar system's habitable zone extends from roughly 1 astronomical unit-- so Earth's orbit-- to 1 and 1/2 AU, covering Earth and Mars.

2017-02-22: The Eye of Sauron Reveals a Forming Solar System!

  • 02:05: That makes Fomalhaut an incredible laboratory for us to study our own solar system and how it may have formed.
  • 04:07: Our own solar system went through this process 4 and 1/2 billion years ago.
  • 04:11: And the solar wind has long since dispersed what was left of our own protoplanetary disk.
  • 08:07: ... formed close together until a close encounter destabilized the whole solar system and flung the gas giants into their current, more spread out ...
  • 09:14: Was our solar system once so Mordor-like?
  • 09:33: Only then can we start to use it to learn about our solar system's early years.
  • 09:54: Brian Cox's Wonders of the Solar System has an awesome episode-- Order Out of Chaos.
  • 09:59: It does a great job describing the forces that shaped our own early solar system.

2017-02-15: Telescopes of Tomorrow

  • 07:23: ... sharpness will actually allow to take photographs of planets in other solar systems and even to observe the spectra of the atmospheres of some ...
  • 08:49: We'll spot countless fast-moving objects in our own solar system, including potentially hazardous asteroids that could one day impact the Earth.

2017-01-25: Why Quasars are so Awesome

  • 01:11: That's surrounded by a solar system-sized whirlpool of superheated plasma that shines brighter than an entire galaxy.
  • 06:39: Most of the energetic craziness happens on a size scale similar to our solar system, or even smaller.

2017-01-19: The Phantom Singularity

  • 00:29: In fact, we still use it to fly spacecraft around the solar system today.

2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer

  • 02:24: These orbits tell us that a dark something of around four million solar masses lurks in the center.

2016-12-21: Have They Seen Us?

  • 11:33: ... within hours, or even minutes, of aliens pointing the facility to our solar system, even if they weren't looking for ...
  • 12:11: However, our steady broadcasts have only washed over a few hundred solar-type star systems and only a few thousand stars total.

2016-12-14: Escape The Kugelblitz Challenge

  • 04:31: Their spaceships form a sphere around the solar system and blast a pulse of light inwards.

2016-10-19: The First Humans on Mars

  • 03:20: ... to protect against high-energy cosmic rays and solar outbursts and from the micrometeorites that also pass easily through ...
  • 05:30: Giant solar arrays stretching across the Martian surface are the obvious answer.
  • 07:28: A lot of what we learn about living on Mars will work elsewhere in the solar system, too.
  • 07:32: In fact, the proposed spacecraft is meant to be a general purpose solar system explorer.

2016-10-12: Black Holes from the Dawn of Time

  • 07:58: It wouldn't be right to end a discussion on primordial black holes without talking about what would happen if one passed through the Solar System.
  • 08:21: ... if it passed by the outskirts of the Solar System, it could shake up the Oort cloud and send a nice rain of comets ...
  • 08:50: They'd just zip right through the solar system unnoticed.

2016-09-29: Life on Europa?

  • 00:58: The moon is increasingly looked at as our best chance to find extraterrestrial life in our solar system.

2016-09-21: Quantum Entanglement and the Great Bohr-Einstein Debate

  • 11:41: Daniel Oberley and others point out that a Von Neumann probe may be in our solar system, but be well hidden.
  • 12:34: ... of bane civilization, there should also be probes blundering through the solar system with no concern about being ...

2016-09-14: Self-Replicating Robots and Galactic Domination

  • 03:50: ... is a tiny spacecraft that will be powered by a solar sail-fed ion drive that could harvest planetary resources to build more ...
  • 05:06: So a spacecraft is launched from the home Solar System with an engine capable of taking it to 10% or 20% lightspeed.
  • 05:34: It deploys initial solar panels and mining bots, and uses these resources to build a factory.
  • 05:42: That factory includes larger solar power plant, a strip-mining operation, and perhaps more assemblers.
  • 07:02: Given B, we should see replication factories in our own solar system.
  • 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.
  • 12:03: But even solar power stations at Earth's surface will soon be a viable solution for most of our current energy needs.
  • 12:12: Mr. Mercury is a little uncomfortable with building a power source that has the potential to destroy our solar system.

2016-08-24: Should We Build a Dyson Sphere?

  • 01:46: The incredible stresses on a solar structure that size are vastly greater than could be sustained by any known or yet imagined material.
  • 01:55: ... than there is non-hydrogen or helium matter in all of the planets in the solar ...
  • 02:36: It's not feasible to build a giant solar sphere.
  • 02:49: ... of building a Dyson sphere, build a Dyson swarm, individual solar collectors that are only kilometers or less in diameter and each with ...
  • 04:13: It would reflect light into a small solar power plant that would then beam energy somewhere useful, perhaps with a laser or a maser.
  • 05:16: ... need to devour Venus, Mars, and a good number of asteroids and outer solar system moons, too, assuming we want to leave Earth ...
  • 06:47: Also, we need a mega structure to harvest it, with a raw material requirement close to that of all the terrestrial planets in the solar system.
  • 08:13: That's nothing, compared to the hundreds of quadrillion solar collectors in a full Dyson swarm.
  • 08:37: However, there's enough mass in the solar system to run a type 3 civilization's Kugelblitz swarm for many times the current age of the universe.

2016-08-10: How the Quantum Eraser Rewrites the Past

  • 11:10: ... like that passing through the solar system, even if nowhere near the Earth, would probably disrupt planetary ...
  • 11:21: Even if it passed by the outer reaches of the solar system, it would perturb the Oort cloud and send swarms of comets plummeting inwards.
  • 11:42: And one of these passing through the solar system would only be dangerous if it was moving slowly enough, and if it came very close to the Earth.

2016-08-03: Can We Survive the Destruction of the Earth? ft. Neal Stephenson

  • 08:14: But there is one threat that no settlement on any planetary surface or space hotel in the solar system can protect us from-- that's an exploding star.
  • 09:44: No planetary surface or space ark in the solar system would be safe from a supernova or a gamma ray burst.
  • 10:09: ... two, get the hell out of the solar system and start colonizing the galaxy beyond the 30-light-year range of ...

2016-07-27: The Quantum Experiment that Broke Reality

  • 11:12: Let's look at some of the comments from our episode on the role of Jupiter in the formation of our solar system.
  • 11:18: ... are around 7.5% the mass of the Sun, while Jupiter is 1/10,000 of a solar ...

2016-07-20: The Future of Gravitational Waves

  • 01:14: This time, they're a bit smaller, at 14 and eight solar masses.

2016-07-06: Juno to Reveal Jupiter's Violent Past

  • 00:14: ... from our point of view, and it holds the secrets to the formation of the solar ...
  • 00:32: It's by far the largest and most massive thing in our solar system after the sun.
  • 00:45: Jupiter's enormous gravity influences the orbit of all the planets in the solar system.
  • 00:50: In fact, its effect during the first billion years of the solar system's formation defines the positions of all planetary orbits.
  • 02:02: It's 20,000 times the strength of Earth's field, giving Jupiter the brightest auroras in the solar system.
  • 02:09: Jupiter patrols the outer solar system at an average distance of 5.2 astronomical units.
  • 02:23: In the wake of its intense gravitational field, it drags with it its own mini solar system of at least 67 moons and a faint ring system.
  • 02:34: That gravitational influence extends through the entire solar system.
  • 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.
  • 03:22: It's more like a giant monster stalking the edge of the garden of the inner solar system.
  • 03:43: But the havoc caused by Jupiter now is nothing compared to the earliest days of the solar system.
  • 03:54: See, the early solar system was a messy place.
  • 04:58: We're going to outline a possible scenario for the first billion years of the solar system.
  • 06:09: But it also solves several problems with the way our inner solar system is currently laid out.
  • 06:54: Our solar system has none.
  • 06:56: ... early rampage into the inner solar system would have sent such planets spiraling into the sun, leaving only ...
  • 07:11: ... comprised of a mixture of materials from both the inner and outer solar system, and that's exactly what you might expect if Jupiter passed ...
  • 07:44: The solar system at this point had all its planets-- eight, maybe nine of them-- but also a huge amount of left over junk.
  • 08:42: As the three outer gas giants plowed through the great field of planetesimals, they scattered this material through the solar system.
  • 09:29: ... the solar system's formation really happened this way or by some completely ...

2016-06-08: New Fundamental Particle Discovered?? + Challenge Winners!

  • 05:52: Bookmaker talks about the connection between solar activity and Earth's climate.
  • 06:01: So it's true that high sunspot activity can increase solar irradiance.
  • 06:06: And in the first half of the 1900s, increasing activity did increase solar output by about 0.1 of a percent.
  • 06:18: But even ignoring this consensus, the correlation between solar activity and warming stopped a while ago.
  • 06:26: As Bookmaker suggests, solar activity is diminishing.

2016-05-04: Will Starshot's Insterstellar Journey Succeed?

  • 02:19: This solar sail has buzzed past Venus and now explores the interplanetary space in an orbit between Earth and Venus.
  • 02:26: Solar sails work well within the solar system and there are a number of plans for more of these.

2016-03-23: How Cosmic Inflation Flattened the Universe

  • 10:28: The Milky Way and our solar system were originally made of gas, giant clouds of the stuff.

2016-03-16: Why is the Earth Round and the Milky Way Flat?

  • 00:23: It loves building spheres like stars, planets, and moons, and disks like spiral galaxies, solar systems, and some crazy stuff like quasars.
  • 01:53: disk-shaped things like galaxies and solar systems have circular symmetry.
  • 08:20: This is not true of things like spiral galaxies, solar systems, and the whirlpools of gas around quasars.

2016-03-02: What’s Wrong With the Big Bang Theory?

  • 10:48: It doesn't work in galaxies or solar systems.
  • 10:51: For example, the solar system is better described with the Schwarzschild metric, dominated by the sun's gravitational field.

2016-02-03: Will Mars or Venus Kill You First?

  • 01:35: ... lack of a strong magnetosphere has allowed the solar wind, the constant stream of energetic particles from the sun, to ...
  • 04:29: See, space is flooded with extremely energetic solar radiation and cosmic rays.
  • 05:21: But that low constant solar wind is nothing compared to a coronal mass ejection.
  • 06:06: ... Mars from the sun and are preceded by some visible indication like a solar flare, whose light reaches you in ...

2015-11-18: 5 Ways to Stop a Killer Asteroid

  • 04:24: See, the Earth is a very small target on the scale of the solar system.

2015-11-05: Why Haven't We Found Alien Life?

  • 06:42: ... the solar wind pushes infested material into interstellar space so that tens of ...

2015-10-15: 5 REAL Possibilities for Interstellar Travel

  • 06:55: ... by massive Helium 3 reactors or in orbit around the sun powered by vast solar ...

2015-09-23: Does Dark Matter BREAK Physics?

  • 03:37: This relationship is definitely true on the scale of the solar system.

2015-08-27: Watch THIS! (New Host + Challenge Winners)

  • 03:15: In 15 billion years, what will you find at the center of the solar system?

2015-08-19: Do Events Inside Black Holes Happen?

  • 05:32: So we associate one solar mass with the black hole itself.
  • 08:50: For instance, the 4 million solar mass black hole at the center of the Milky Way is about as dense as water.
  • 09:05: ... even though a solar mass black hole would spaghettify you from pretty far away, you could ...

2015-07-08: The Leap Second Explained

  • 00:22: Back in the day, the second was defined as exactly 1/86,400 of a solar day.
  • 00:30: Thus, in 1960, the second was redefined to be whatever would make the motions of multiple objects in the solar system fit Newton's laws of motion.
  • 01:05: ... has gotten about 2 and 1/2 milliseconds longer so that by the 1960s, one solar day was now 86,400.0025 new ...
  • 01:19: As a result of all this unit shifting, the current solar day right now is already 2 and 1/2 official milliseconds longer than 24 hours.

2015-06-24: The Calendar, Australia & White Christmas

  • 02:26: Instead, it's locked to the solar year, to the seasons, so that it backtracks along Earth's orbit right along with the equinoxes and the solstices.
  • 04:40: ... spinning down due to its interactions with the moon, so that the mean solar day is getting longer, by about one to two milliseconds every 100 ...
  • 06:45: ... because these things are going to get blown out of orbit by the solar wind without some kind of ...

2015-06-17: How to Signal Aliens

  • 04:35: So I'm picturing an ultra-thin, ultra-lightweight, opaque material that we could launch into solar orbit and then unroll like a sail.
  • 04:45: Now, we would need to tweak the orbit occasionally due to solar wind and radiation pressure.
  • 04:49: ... if that could be automated or if space maintenance missions inside the solar system become easier for us in the future, then this setup could serve ...

2015-06-03: Is Gravity An Illusion?

  • 10:57: ... when we're never going to go there and we still haven't explored our own solar ...

2015-03-11: What Will Destroy Planet Earth?

  • 00:34: About as much solar energy as a whole Earth receives over 40 million years.
  • 02:18: In fact, a head-on collision between Earth and any solar system object deflected into our path will top out at a mere 70 to 80 kilometers per second.
  • 03:00: ... some French physicists ran 2,500 distinct simulations of the solar system's evolution over the next few billion ...
  • 03:14: OK, you know that diorama of the solar system you made back in fifth grade?
  • 04:09: See, another paper in the description works out that an Earth-like planet in a solar atmosphere would vaporize after a few million years.
  • 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.

2015-03-04: Should We Colonize Venus Instead of Mars?

  • 00:39: Basically, Venus has the worst public relations team in the solar system.
  • 01:45: It's closer to the sun, which means about four times more available solar power then you have on Mars.
  • 04:54: ... like the upper atmosphere of Venus might be the closest thing in the solar system to an Earth-like ...

2015-02-25: How Do You Measure the Size of the Universe?

  • 00:26: The diameter of the solar system is about 8 light hours or 9 billion kilometers.

2015-02-18: Is It Irrational to Believe in Aliens?

  • 03:51: Remember, our species, which is only about 200,000 years old, has already sent the Pioneer and Voyager probes out of the solar system.

2015-02-11: What Planet Is Super Mario World?

  • 04:49: So Super Mario World is clearly not in our solar system.
  • 04:52: ... to planets outside the solar system are trickier, because astronomers don't have good estimates of ...
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