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2022-11-23: How To See Black Holes By Catching Neutrinos

  • 11:00: The only other sure neutrino detections from space are the Sun and the remnant of supernova 1987A in the large magellanic cloud.

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

  • 12:52: ... we’ll see changes in   all of this. That means we can remove cloud cover, track the change from day to night,   see seasonal and tidal ...

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

  • 00:00: ... weather check and came back looking  annoyed to report two gigantic clouds in the sky.   I went to look - it was the most  crystal ...
  • 01:41: ... Way. We can predict its future mergers with   the Magellanic clouds and Andromeda - but perhaps more astonishing, we can reconstruct ...
  • 07:58: ... way. It’s home to the spiral  arms and the big, bright star forming clouds   and our sun. We did an episode on why galaxies  become flat disks - ...
  • 12:11: ... two brightest satellite  galaxies, the Large and Small Magellanic Clouds,   are currently making their first pass. Already,  we see them being ...

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

  • 03:40: ... great spiral arms of the Milky Way’s disk.   While most of the cloud ended up in the shrinking  spheroid that would ultimately become ...
  • 05:52: ... “Metallicity” is our measure of the  heavy element content of a cloud   or a star. It comes from the fact that astronomers  tend to call ...
  • 06:56: ... - as a slightly overdense spot  in the near perfectly smooth cloud of particles   that filled the universe after the Big Bang. ...
  • 08:01: ... These stars fell towards the center of  the still-collapsing gas cloud like pebbles in a   pond, forming a growing cluster that would ...
  • 09:26: ... In our solar system, such encounters   disturb our Oort cloud, sending comets plummeting  towards the inner solar system. A ...

2022-03-30: Could The Universe Be Inside A Black Hole?

  • 08:15: ... They approximated the collapse of a star by modeling it as a spherical cloud of matter with a perfectly homogeneous density and zero ...
  • 08:36: ... gravity and an event horizon forms around it, but within the collapsing cloud the matter remains homogeneous and the spacetime is flat until it ...

2022-03-23: Where Is The Center of The Universe?

  • 12:09: ... was distributed with constant density across a spherically symmetric cloud, but beyond that cloud the density could change, or space could be ...
  • 12:19: ... found that an observer in a sufficiently large cloud that was expanding or contracting would observe an expanding or ...
  • 12:32: ... metric. Such a universe would have a center - the center of the cloud, assuming the cloud is ...

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

  • 09:53: We can see how stars form in multitudes from  collapsing gas clouds, and how planets then coalesce in the disks surrounding those stars.

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

  • 05:06: ... example we have protostars - the clouds of gas in the process of collapsing into a new star, circumstellar disks ...
  • 05:40: So yeah, we could go flicking through the frequency channels of gas clouds looking for alien TV shows.

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

  • 07:05: ... asteroid-mass black hole at the absolute top end of our mass range, the cloud of plasma is barely microns in size, but it still shines with the power ...

2021-07-21: How Magnetism Shapes The Universe

  • 09:53: Magnetic fields generated by collapsing gas clouds help to slow the rotation of those clouds - expel angular momentum.
  • 10:00: Without that, those clouds would never be able to collapse all the way into stars.

2021-07-07: Electrons DO NOT Spin

  • 17:29: ... Mwangi also dropped some knowledge,  informing us that “The Cloud” - is actually named after Dr, Shannon, the founder of the  field of ...

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

  • 01:22: ... orbit in the midst of a giant cloud of debris - rocket boosters, protective shields, old broken satellites ...
  • 11:21: The Kessler syndrome accelerates, churning up low earth orbit into a cloud of shrapnel.

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

  • 09:21: ... the obscuring stuff filters the star’s light i n a way consistent with clouds of particulates - space dust, rather than an opaque object. So we’re ...

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

  • 08:52: ... Magellanic Clouds are especially good for this - the low level of microlensing of stars in ...
  • 09:07: ... even if MACHOs aren’t all of dark matter, studies of the Magellanic Clouds and Andromeda have found enough microlensing events to suggest that 20% ...

2020-10-05: Venus May Have Life!

  • 01:40: ... atmosphere also sports a permanent thick layer of sulfuric acid clouds, So yeah, when we realized just out just how awful Venus was, our ...
  • 02:22: ... other weird thing is that the clouds of Venus appear to absorb the Sun’s light in a weird way - more short ...
  • 02:55: ... surface, it’s a paradise, and we talked about the possibility of human cloud-city settlements in a previous ...
  • 07:00: You might get some produced by lightning strikes in the cloud layers, or by cosmic rays hitting the upper atmosphere.
  • 08:07: But the requirements for life in the clouds of Venus are pretty strict.
  • 10:20: These spores are extremely tiny and light, and so they float in the haze below Venus’s cloud banks.

2020-09-08: The Truth About Beauty in Physics

  • 14:47: ... the other hand, if you have a cloud of gas hanging out in space like a nebula - it will be illuminated by ...
  • 15:05: You won't see absorption unless you look directly through the cloud at one of those stars.

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

  • 07:10: ... that told how much of each ionization state you should get if you have a cloud of some element at a given temperature and ...

2020-08-24: Can Future Colliders Break the Standard Model?

  • 16:54: ... gives you a supernova and leaves nothing behind but a pretty cloud of gas Leandro asks how we manage to get such good sound quality out ...

2020-05-04: How We Know The Universe is Ancient

  • 09:39: ... had originally made an awkward mistake - they had been counting bright clouds of hydrogen gas - so-called HII regions - as stars, which threw their ...

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

  • 00:47: ... of the Sun, but it also swarms with smaller black holes, searing hot clouds of gas, massive stars right on the edge of going supernova, and some of ...
  • 03:18: ... of a diffuse cloud of gamma rays, they saw a massive pair of high-energy gamma ray bubbles ...

2020-02-18: Does Consciousness Influence Quantum Mechanics?

  • 03:20: ... we make that measurement the wavefunction “collapses” - it goes from a cloud of possible final destinations for the electron to a more or less ...
  • 03:34: ... because our large-scale, classical world isn’t made of probability clouds, it’s made of objects with clearly definable ...

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

  • 06:13: Stars are formed when giant clouds of gas collapse under their own gravity.
  • 06:37: ... elements and molecules allow clouds to cool and stars to form much more quickly, and of these, carbon ...

2019-09-16: Could We Terraform Mars?

  • 18:29: ... isn't nearly as strong as Earth's, however, so our Venusian floating cloud cities had better still have very thick ...

2019-07-25: Deciphering The Vast Scale of the Universe

  • 01:53: But as far as we knew they were just clouds of gas inside our own galaxy.

2019-07-15: The Quantum Internet

  • 09:27: ... solutions, ranging from storing entangled photon quantum states in a cloud of caesium atoms, a kind of quantum atomic disk drive, or the spin-state ...

2019-06-20: The Quasar from The Beginning of Time

  • 03:57: The infrared Andromeda is a swirl of star-forming clouds and gas.

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

  • 02:47: ... forest to map where along the line of sight to a quasar there are clouds of hydrogen gas and learn about their size and density based on the ...

2019-05-16: The Cosmic Dark Ages

  • 10:47: ... the Lyman-alpha forest, where the quasar light passed through individual clouds of neutral gas, each of which cut a narrow slice out of the ...

2018-11-21: 'Oumuamua Is Not Aliens

  • 08:56: For example, it may be that stars release their Oort Clouds, when they die.
  • 09:01: ... every star that passed before us shed its vast cloud of comets into the galaxy, that would make plenty enough interstellar ...
  • 09:22: ... from outside our solar system at all, but rather comes from our own Oort cloud and was socked from its orbit by impact and or gravitational interaction ...

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

  • 02:15: He guessed that both of these resulted from surface water, clouds, and ice.

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.

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

  • 01:41: ... there was originally no way to know whether Andromeda was a much smaller cloud of gas, a nebula inside our galaxy, or whether it was a galaxy in its ...

2018-02-21: The Death of the Sun

  • 00:46: They're born inside a cloud of gas and dust.

2018-02-14: What is Energy?

  • 12:40: These star-forming clouds can vary in metallicity across their vast widths, which are often hundreds of light years.

2018-01-31: Kronos: Devourer Of Worlds

  • 00:28: [FUTURISTIC MUSIC] Our story begins where every story begins, in the heart of a vast cloud of gas and dust drifting through interstellar space.
  • 01:14: Binary stars typically have the same chemical composition as each other, having formed from the same cloud.
  • 02:06: They also allow us to test to what degree stars that formed in the same cloud share a chemical signature.
  • 04:43: These stars definitely formed from the same molecular cloud.
  • 04:56: But if they formed from the same cloud, they should be made of the same stuff, right?

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

  • 01:28: ... the sun was born, it's initial gravitational collapse from a giant gas cloud was halted as soon as the core became dense enough, dense enough for ...
  • 07:21: The increase in cloud cover may reflect some of the extra radiation.

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

  • 04:39: The first is that it originated in our Kuiper belt Oort cloud.
  • 05:35: They found that the object passed through the Oort cloud of another star, the unpoetically named TYC4742-102701 around 1.3 million years ago.
  • 07:35: Now that's higher than the density of comet like objects in the Oort cloud.

2017-12-06: Understanding the Uncertainty Principle with Quantum Fourier Series

  • 13:58: ... the light echo from a dead quasar that was once in that galaxy, so the cloud of gas ionized by the last burp of energy from an active supermassive ...

2017-11-22: Suicide Space Robots

  • 07:33: Tens of millions of kilograms of comet were ejected in a debris cloud to be analyzed by the surviving spacecraft component of Deep Impact.

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

  • 06:48: When a quasar's light passes through giant clouds of gas on its way to us, elements in those clouds absorb photons to produce spectral lines.
  • 06:58: By looking at many quasars, we can find absorbing clouds that existed in different past epochs of the universe.
  • 07:18: They used the Keck telescope in Hawaii to study iron and magnesium absorption lines from clouds along the lines of sight of 143 quasars.
  • 08:26: ... really difficult. Photons from these extremely distant quasars and gas clouds are massively redshifted-- their wavelengths stretched out due to the ...

2017-09-20: The Future of Space Telescopes

  • 04:24: We'll be able to detect continents, oceans, icecaps, and cloud banks of faraway worlds.
  • 07:41: ... a terrestrial planet at tens of light years distance and even map the cloud structure of a gas giant, especially if you add a starshade to the ...
  • 08:46: ... the sky, scientists have proposed we use photon pressure to suspend a cloud of tiny reflective particles in Earth's ...
  • 08:58: A laser can find a glitter cloud, if you will.
  • 10:47: ... when the first orbiting rainbow is launched and that sparkling glitter cloud is thrown into the universe, we will consider it to be a celebration of ...

2017-08-16: Extraterrestrial Superstorms

  • 03:04: As it cools, it condenses into clouds, which are driven outwards.
  • 05:02: Most of Jupiter's visible clouds are ammonia ice, tainted with colorful impurities, but there also clouds of hydrogen sulfide and regular H2O.
  • 07:56: ... probe will swing within 3,400 kilometers of the Jovian cloud tops and ultimately crash into them to avoid contaminating potentially ...
  • 08:10: ... atmospherics high-pressure depths, an imaging spectrograph for studying cloud chemistry, a magnetometer for measuring Jupiter's intense magnetic ...
  • 08:48: This is perfect for measuring cloud heights and also to record horizontal cloud drift, which gives us wind speeds.
  • 09:16: All of these images were taken on July 10 during Juno's seventh flyby from just 5,600 kilometers above the clouds.

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

  • 01:01: ... long before the sun was even a twinkle in the eye of a giant molecular cloud. ...
  • 05:52: Stars form when vast clouds of mostly molecular hydrogen collapse under their own gravity.
  • 05:58: Now, for that collapse to proceed, the pull of gravity needs to overcome the cloud's own internal thermal pressure.
  • 06:05: Warm clouds have more internal energy, helping them to stay puffed up against their own gravity.
  • 06:12: To collapse into stars, clouds have to cool.
  • 06:22: As these metals get jostled in a warm cloud, their electrons absorb energy, jumping up in energy levels.
  • 06:39: Those photons quickly escape the cloud, taking energy with them, and helping to cool things down.
  • 06:45: ... when there's a metal-rich giant molecular cloud that begins to contract under its own gravity, it can shed its thermal ...
  • 06:58: Unimpeded by pesky thermal pressure, the cloud collapses quickly.
  • 07:03: In fact, any over-dense lump within the cloud will, itself, collapse, causing the cloud to fragment.
  • 07:17: At that point, the contraction is much slower, and those cloud fragments become stars.
  • 07:22: But without materials to help cooling, a giant cloud of pristine hydrogen helium gas can't shed its heat quickly enough.
  • 07:37: Pressure and temperature have time to equalize across the cloud before it breaks apart.
  • 07:44: The result is much larger cloud chunks that evolve into gigantic stars.
  • 07:51: By the way, this sort of cloud fragmentation is described by the Jeans instability.

2017-05-10: The Great American Eclipse

  • 08:12: Have a backup plan in case of clouds, and of course, be checking the weather forecasts several days earlier.

2017-05-03: Are We Living in an Ancestor Simulation? ft. Neil deGrasse Tyson

  • 15:06: ... principle, if you were to take such an expanded cloud of particles and exactly reverse their velocities, then they would all ...
  • 15:37: Because particles can be pushed beyond the edge of the cloud, there end up being somewhat more interactions driving particles outwards than inwards.

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

  • 10:48: ... equal to the gene's length, which itself is the maximum size region of cloud can be before it fragments, because local gravitational collapse happens ...
  • 11:23: As long as the cloud is still smaller than the gene's length, it won't fragment further and a single star will form.

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

  • 02:14: Start with a dense core in a giant molecular cloud.
  • 02:32: And you have a hot protostar surrounded by a great cloud of dust and gas.
  • 08:34: Stars typically form in groups as very large clouds of molecular hydrogen collapse and break apart into separate pieces.

2017-01-25: Why Quasars are so Awesome

  • 00:42: Giant molecular clouds-- beautiful and tranquil, but also screaming vortices spitting stars into the cosmos.

2016-11-16: Strange Stars

  • 09:08: Even the famous supernova that exploded in the Large Magellanic Cloud in 1987 has been hypothesized to have left behind a quark star.

2016-10-26: The Many Worlds of the Quantum Multiverse

  • 00:44: Instead, they seem to behave as probability clouds of all properties they might have were we to try to measure them.

2016-10-19: The First Humans on Mars

  • 07:39: Mars will be fun, but we're really holding out for those Venusian cloud cities here at Space Time.

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

  • 08:21: ... passed by the outskirts of the Solar System, it could shake up the Oort cloud and send a nice rain of comets to pepper the inner Solar ...

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

  • 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.

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

  • 11:58: It's called "the Jeans mass." It depends on cloud size, temperature, rotation rate, and composition.
  • 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.

2016-04-13: Will the Universe Expand Forever?

  • 12:11: And so, by now, it's wandered very far from the giant cloud of gas from which it formed.
  • 12:18: That cloud is long gone, anyway.
  • 12:35: ... more will be from previous generations of stars that enriched that giant cloud before it formed stars of its ...

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?

  • 08:42: Let's think about what happens when a vast interstellar cloud of gas and dust collapses to form a star.
  • 09:10: This global rotation makes it even harder for the cloud to collapse.
  • 09:28: The cloud can still collapse in the down direction, and it does so, ending up as a spinning disk when it finds itself in equilibrium.

2016-02-11: LIGO's First Detection of Gravitational Waves!

  • 07:42: In terms of a long-term colony, Venusian cloud cities are going to be much healthier.
  • 08:03: Venus' surface, or even cloud city gravity, is 90% that of Earth's.
  • 08:12: Laura Lorca wants to know exactly how to build a cloud city.

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

  • 06:35: But we discussed a much better option in a previous episode-- floating cloud cities at an altitude of 50 kilometers.
  • 06:49: You decide to go for a nice walk outside to catch the views from the cloud city.
  • 07:10: Unfortunately, it's almost always cloudy, because at 50 kilometers you're right at the base of the Venusian cloud layer.
  • 07:42: It just means that your pleasant stroll through the cloud city has to be done in an acid-proof, heat-resistant suit with an air tank.

2015-12-09: How to Build a Black Hole

  • 05:35: ... neutron, for instance, is not in any one place but exists as a cloud of possible locations that might be tightly constrained or maybe very ...
  • 05:46: Location remains a possibility cloud until the neutron interacts with another particle, at which point, its location is resolved.

2015-09-30: What Happens At The Edge Of The Universe?

  • 08:51: By comparison, the cold hydrogen gas that fills our galaxy clumps together in giant clouds.
  • 08:57: But then these clouds radiate light in different ways, allowing the gas to cool even more and collapse into stars.

2015-05-13: 9 NASA Technologies Shaping YOUR Future

  • 09:06: Talia Enright pointed out that all these arguments could apply to a #OccupyVenus Cloud City mission.

2015-05-06: Should the First Mars Mission Be All Women?

  • 00:18: Look, it's no secret that we here at "Space Time" love the idea of cloud cities on Venus.

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

  • 05:03: So it might make sense to colonize Venus with cloud cities.
  • 05:30: We are very far from sending this guy to lead our Venutian Cloud City.
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