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

  • 13:25: ... Venusian atmosphere is almost entirely carbon dioxide, creating a greenhouse effect that ...
  • 14:11: All of that is buried beneath extremely thick atmospheres of gas-phase mostly-hydrogen.

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

  • 06:09: More challenging are confounding particles from our own atmosphere.
  • 06:13: When cosmic rays hit molecules in our atmosphere, many different particles can be produced, but the most annoying are muons and neutrinos.
  • 07:26: There’s only about 50 neutrinos more than you would expected from cosmic rays in the atmosphere, but it’s pretty clearly something out there in space.

2022-11-16: Are there Undiscovered Elements Beyond The Periodic Table?

  • 05:01: ... nature because it’s created when cosmic rays hit nitrogen nuclei in the atmosphere. ...

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

  • 00:33: ... is helping - it can   detect different molecules in the atmospheres of exoplanets a bit larger than the Earth. JWST   will even take ...

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

  • 00:19: ... pretty amazing stuff, from colliding galaxies to planets and exoplanet atmospheres to the earliest, most distant galaxies ever ...
  • 05:09: ... also let’s us see the atmospheres of planets in other solar systems, which is an important step towards ...

2022-06-22: Is Interstellar Travel Impossible?

  • 07:34: Think about a satellite or meteoroid entering the Earth’s atmosphere.
  • 08:02: Interstellar space is quite a bit less dense than the upper atmosphere - by a factor of around 10^16.

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

  • 14:38: ... rocky or icy core forms to start  holding on to hydrogen and helium atmospheres.   That needs to happen before the star turns on and blasts away all ...

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

  • 03:40: ... planets like the Earth, while the larger collected  vast atmospheres of hydrogen and helium and became   the gas giants. At the ...
  • 08:01: ... may lead to excessive mutation and degradation of   the atmosphere. For example, a supernova within  150 light years would obliterate ...

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

  • 15:57: Life draws carbon from the atmosphere and sequestered in the crust.

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

  • 03:22: ... from electron transitions in the atoms and molecules of the star’s atmosphere. ...
  • 09:04: But is it similar enough to have an atmosphere?
  • 09:50: For one thing, unless there’s a lot of atmospheric circulation, that permanent night could cause the atmosphere to collapse, freezing to the surface.
  • 11:43: ... sufficiently thick atmosphere and strong planetary magnetic field could in principle protect any ...
  • 12:38: ... order for Proxima B’s hypothetical oceans and atmosphere to have survived this earlier, hotter period it would have to have ...
  • 13:19: ... sensitive enough to detect emission lines from molecules in Proxima B’s atmosphere, if it has one, or even the light reflected from the planet’s ...
  • 14:45: Four lights are visible through the thick atmosphere - the gleaming white twins Tolimar and Rigel Kentaurus, the glowering red orb of Proxima herself.

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

  • 06:02: ... talk about what happens when our black hole first enters the atmosphere. In the immediate surroundings of any black hole, gravity accelerates ...
  • 07:29: ... such a black hole passed into our atmosphere, it would look like the brightest shooting star you’ve ever seen, ...
  • 08:16: ... there was only one shockwave detected in the Earth’s atmosphere, and a black hole’s exit on the other side of the planet should have made ...
  • 08:41: ... black hole, the more likely it is we’d miss it as it passed through the atmosphere. ...
  • 10:16: ... neither the earth’s atmosphere nor its surface would keep a good record of micro black holes hitting ...

2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe

  • 02:35: ... surface   is a little fuzzy. We’re seeing the star’s  atmosphere. Similar to Earth’s atmosphere,   this layer of haze starts ...
  • 03:07: ... the neutron star’s atmosphere  is not made of atoms, rather it's a plasma,   in which atoms ...
  • 03:27: ... while Earth’s atmosphere is something like 100 km thick, depending on how you define the ...
  • 04:04: ... degeneracy pressure stops further collapse and ultimately holds the atmosphere ...

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

  • 04:17: Below around 1000 km, Earth’s atmosphere is incredibly diffuse but still present.
  • 04:31: ... during times of high solar activity when more energy is pumped into the atmosphere, causing it to puff up and cause increased drag to higher ...
  • 05:41: I already mentioned that orbits decay due to interaction with the upper reaches of Earth’s atmosphere.
  • 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

  • 05:11: ... 2020 Astronomers reported the signature of phosphine in the upper atmosphere of Venus from radio data taken with ALMA, the Atacama Large ...
  • 11:24: ... is a dangerously active red dwarf - it’s unlikely that any planetary atmosphere could survive ts outbursts. It’s also so close! If there’s a ...

2021-03-16: The NEW Crisis in Cosmology

  • 08:03: ... telescopes in space - above   the blurring effect of Earth’s atmosphere it’s possible to make better position measurements.   The ...

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

  • 13:21: Last episode we reported on the incredible discovery of possible biosignatures in the atmosphere of Venus.
  • 15:37: ... to kindly shut down their factories so we can more carefully analize the atmosphere for much more interesting ...

2020-10-05: Venus May Have Life!

  • 00:32: And yet the horrible hellhole that is the atmosphere of Venus has just yielded perhaps the most exciting lead for extraterrestrial life.
  • 00:38: Arguably, it’s our only lead - the faint signature of the chemical phosphine in Venus’s atmosphere, which may have been produced by living organisms.
  • 01:28: Its atmosphere is 100 times the mass of Earth’s and mostly carbon dioxide.
  • 01:40: ... atmosphere also sports a permanent thick layer of sulfuric acid clouds, So yeah, ...
  • 03:05: ... life might exist permanently aloft in Venus’s relatively habitable upper atmosphere. ...
  • 03:31: ... to detect so-called atmospheric biosignatures - chemicals in a planet’s atmosphere that are very hard to explain without the presence of ...
  • 03:44: There are lots of ways to do this - for example seeing the effect on a star’s light as it passes through its own planets atmospheres.
  • 03:51: Another possibility is to look for the absorption of the planet’s own light as it emerges from deep within its atmosphere.
  • 04:48: ... Array - and confirmed that there had to be phosphine in the upper atmosphere of ...
  • 06:41: The stuff is very quickly oxidized - particularly in the highly acidic atmosphere of Venus.
  • 07:00: You might get some produced by lightning strikes in the cloud layers, or by cosmic rays hitting the upper atmosphere.
  • 07:07: Most of the non-biological production is likely to happen at the surface, and would take years to diffuse to the upper atmosphere.
  • 08:32: ... to be essential to life, and in the extreme dryness of the Venusian atmosphere free-floating microbes would quickly dry ...
  • 09:07: These droplets can only exist in a narrow range in the atmosphere.
  • 09:11: ... grow they begin to fall back down into the crushing oven of the lower atmosphere, where they quickly evaporate ...
  • 09:56: So what if Venusian microbes passed through such a spore state in the lower atmosphere?
  • 10:03: The life cycle would look like this: microbes are in a metabolic state in sulphuric acid droplets in the upper atmosphere.
  • 11:04: ... lifeforms in its atmosphere today must have evolved from presumably much more sensible critters that ...
  • 12:07: Ultimately we want to bring back samples of the Venusian atmosphere - to actually get microbes under a microscope, if they exist.

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

  • 14:42: That's the case when looking through the Sun's atmosphere at it's bright interior.

2020-08-17: How Stars Destroy Each Other

  • 01:22: ... storm of fusion ripped around the planet-sized white dwarf, spraying its atmosphere into space and for a couple of weeks shining 10s of thousands of times ...

2020-07-08: Does Antimatter Explain Why There's Something Rather Than Nothing?

  • 05:43: ... example in the Sun, or in radioactive decay, or when cosmic rays hit the atmosphere, which is how antimatter was discovered in the first ...

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

  • 04:32: ... of alien life is to find signatures of its chemical activity in the atmospheres of alien ...
  • 04:43: ... plucked from the starlight due to it passing through that planet’s atmosphere. ...
  • 04:57: Cellular life massively alters the atmosphere because it excretes gases - oxygen, methane, nitrous oxide as that light metabolizes.
  • 07:12: Earth’s upper atmosphere is thick with bacteria and viruses - mostly swept into the atmosphere from the oceans by seaspray.
  • 07:26: ... light droplets can be lifted to the very edge of an atmosphere with the help of the planet’s magnetic field and then swept into ...

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

  • 00:00: ... band from an emission line hydrogen-alpha I think it is in the upper atmosphere of the Sun so you see these incredible details of the strung of the ...

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

  • 12:09: ... extra gamma rays being generated by this process, because our Earth’s atmosphere absorbs most of the gamma ray radiation that comes our ...

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

  • 08:25: ... of the earth because it’s produced when cosmic rays hit nitrogen in the atmosphere, resulting in a constant proportion of C-14 within the atmospheric ...
  • 08:42: ... carbon is incorporated from the atmosphere into living organism by photosynthesis, but when the plant, or whatever ...

2020-01-13: How To Capture Black Holes

  • 04:50: ... like how a satellite’s orbit will decay if it’s too close to Earth’s atmosphere. ...

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

  • 06:35: ... recycles nutrients from the crust into the mantle and then back into the atmosphere through volcanic ...
  • 10:04: ... other possible rare Earth factors - we may have an unusually hospitable atmosphere and water content and may have been lucky in avoiding various cosmic ...

2019-09-23: Is Pluto a Planet?

  • 16:05: We'd also need far less material than it would take to rebuild the Martian atmosphere.
  • 16:19: After all, it's closer in mass to the Earth and has an atmosphere - albeit a searing hot, horribly acidic one.
  • 16:47: The magnetic field that it does have comes from the interaction of the solar wind with its super thick atmosphere.
  • 16:52: But presumedly, we'd need to massively alter and even reduce that atmosphere, if we want to terraform it, which would probably kill the field.

2019-09-16: Could We Terraform Mars?

  • 01:31: In the end it’s a question of atmosphere.
  • 01:55: On Earth that same light first bounces around in our thick atmosphere, heating it up.
  • 02:05: But even if the planet were warmer, liquid water would still be impossible in that thin atmosphere – it sublimates directly from ice to gas.
  • 02:15: And of course Earth’s atmosphere protects us from harmful cosmic rays and the most dangerous ultraviolet radiation from the Sun.
  • 02:26: So, the most important step in terraforming Mars is to give it an atmosphere – ideally as close to Earth’s as possible.
  • 02:41: After all, Mars WAS once a warmer, watery planet with a much thicker atmosphere.
  • 02:55: The hope then, is that this water and the atmosphere that once supported it is now all locked in the planet’s crust and ice caps.
  • 03:20: There’s a real risk that Mars actually lost its atmosphere to space, rather than absorbed it into the surface.
  • 03:33: At 11% the mass of Earth, it has a weaker gravitational field that grips less tightly to an atmosphere.
  • 03:54: The unprotected and loosely bound Martian atmosphere may have been slowly shaved away by that wind over billions of years.
  • 04:06: The ablation of what is left of the Martian atmosphere has now been directly observed by NASA’s MAVEN spacecraft, as we’ve also discussed before.
  • 04:23: ... of using the remaining surface carbon dioxide to replenish the Martian atmosphere, based on observations of NASA’s Mars Reconnaissance Orbiter and Mars ...
  • 04:54: And… unfortunately they conclude that no near-future technology could hope to to kickstart the recovery of any useful atmosphere.
  • 05:34: ... were released, it would maybe double the current amount of CO2 in the atmosphere – which is a factor of around 100 times too low to make a ...
  • 06:49: And that’s really our only hope to find enough CO2 - or really any native Martian material - to replenish the atmosphere.
  • 07:19: Seriously, that’s how much atmosphere is above your head right now.
  • 09:18: ... could get us a carbon dioxide-oxygen atmosphere in a few decades, or in centuries … or millenia if you scale down the ...
  • 09:56: Our brand new CO2-oxygen atmosphere is not exactly earth-like.
  • 10:06: ... algaes can survive in a pure CO2 atmosphere –which is handy, because blue-green algae – cyanobacteria - was ...
  • 10:18: And we’ll need that photosynthesis because otherwise oxygen will be quickly leeched from the atmosphere as it oxidizes the surface.
  • 10:38: And perhaps eventually a breed of post-humans genetically or even cybernetically adapted to deal with a CO2 atmosphere.
  • 10:46: I just described the “easy” path to building an atmosphere on Mars.
  • 11:03: At any rate, to get a true Earth-like atmosphere we need a non-toxic filler molecule.
  • 11:18: To really build an Earth-like atmosphere we have to turn our eyes to the rest of the solar system.
  • 11:58: So, to build a quadrillion-ton nitrogen atmosphere that’s, like, 10,000 comets.
  • 12:41: Once Mars has been suitably bombarded there’s still a lot of work tweaking the new atmosphere.
  • 12:59: Mars has an atmosphere – either released from deep in the crust or brought in from the far outer solar system.
  • 13:06: The last step is to protect the new atmosphere.
  • 13:27: The resources and energy needed to build this is insane – but hey, we just built an atmosphere, so why not?
  • 14:28: ... several orders of magnitude less material than building an entire atmosphere. ...
  • 14:48: Now, without a real atmosphere, space radiation is gonna be a problem for our worldhouse, as is the constant bombardment of micro-meteors.
  • 18:06: ... an Earth-type intrinsic magnetic field, the solar wind striking its atmosphere creates an induced magnetic field that does protects the ...
  • 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.
  • 01:13: Would we lose our atmosphere?

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

  • 00:33: ... kilogram of coal and worse per ton of carbon dioxide released into the atmosphere At the other end of the spectrum is the energy released when particles ...

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

  • 01:10: ... being on another planet. I can already feel the effect of the thinner atmosphere. My natural impulse, bizarrely, is to hold my breath. Must remember to ...
  • 03:45: ... atmosphere is transparent to visible light, so a ground-based telescope can see a ...
  • 04:01: ... infrared light also makes it through the atmosphere, though it helps to be up here on a mountaintop. Although the air above ...

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

  • 07:31: ... space, and also, hovering above the accretion disk we have a hot atmosphere that radiates ...

2018-12-12: Quantum Physics in a Mirror Universe

  • 00:02: ... probes carrying super resistant life-forms well maybe let's get our atmosphere sniffing telescopes up and running to see what's already out there first ...

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

  • 00:37: ... of up to hundreds of thousands of GS and hundreds of thousands of Earth atmospheres in shock pressure similar forces apply when it smacks down at the other ...

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

  • 02:36: To answer this question, we'll need to look at the composition of their atmospheres.
  • 02:42: Life is expected to massively alter the chemical composition of its home world atmosphere.

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

  • 03:10: ... annually and thought he saw what he calls a comfortable but modest atmosphere. ...
  • 03:27: ... Herschel was a fantastic astronomer, but his wrongness about Mars's atmosphere is a nice example that even the smartest of us see what we want to ...
  • 10:48: One reported the detection of methane in the atmosphere.

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

  • 05:47: While we've used heat shields before on a spacecraft or rovers for entering atmospheres, this one is different.

2018-04-25: Black Hole Swarms

  • 01:43: Colder and hence denser water or air, sinks to the bottom of the ocean or the atmosphere.

2018-04-11: The Physics of Life (ft. It's Okay to be Smart & PBS Eons!)

  • 03:56: ... light warms the atmosphere in the oceans and it powers photosynthesis at the bottom of the food ...

2018-01-31: Kronos: Devourer Of Worlds

  • 03:49: Stellar spectra are thick, with sharp emission and absorption features that result from electron transitions in atoms in the star's atmosphere.
  • 08:34: ... or nano-particles, because A, it doesn't change the chemistry of the atmosphere, and B, we get unlimited free ...

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

  • 03:37: And this is due to CO2 leaching from the atmosphere.
  • 05:12: ... outside the outer edge of the habitable zone, at least given its current atmosphere. ...
  • 05:48: But planet surface temperature and the location of the habitable zone depends on the planet's atmosphere as well as the star's brighteners.
  • 06:31: And depending on how our atmosphere evolves, our beautiful blue orb may become a desert planet relatively soon.
  • 09:06: Unfortunately, it has neither the mass nor the atmosphere needed to retain the released water.
  • 09:11: It'll be lost to space just like its initial atmosphere was.
  • 09:15: But perhaps we'll have advanced to the point of being able to replenish the Martian atmosphere by then.
  • 09:33: ... seeding the upper atmosphere with reflective nanoparticles might do the trick, assuming humans or our ...

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

  • 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.

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

  • 01:17: ... that could happen any time-- a supernova or gamma-ray burst frying our atmosphere. ...
  • 03:50: Essentially, all of the gamma rays and x-rays are going to be blocked by our atmosphere.
  • 04:00: Instead, the danger is in the long-term effects on the atmosphere.
  • 04:05: ... rays break apart nitrogen and oxygen molecules in the atmosphere, which then recombine into various oxides of nitrogen. Those molecules ...
  • 04:28: These dangerous molecules can remain in the atmosphere for a few years.
  • 09:31: But with any luck, we'll have advanced to the stage where geoengineering of the entire atmosphere is possible.
  • 11:36: ... Oumuamua is entirely rocky and hit the atmosphere pretty much head on, it might actually reach the ground before ...

2017-11-22: Suicide Space Robots

  • 01:10: Venus, with its dead searing hot atmosphere, is the most ravenous consumer of Earth-made landers.
  • 01:20: From 1966 to 1982, 12 probes from the Soviet Venera program were devoured by Venus's atmosphere.
  • 01:38: It fought against the blistering 445 Celsius heat and crushing 90 atmosphere pressure for 23 minutes before going quiet.
  • 01:48: ... of another planet-- accurate temperature and pressure readings of the atmosphere that killed ...
  • 01:57: These measurements would have been impossible outside Venus' thick atmosphere.
  • 02:23: ... some ways, it's harder to land things on Mars due to its extremely thin atmosphere, which makes parachuted-assisted soft landings very difficult. There's a ...
  • 03:26: But this time, the alien atmosphere proved the savior, rather than the destroyer of robots.
  • 06:03: On September 15, 2017, Cassini was plunged into Saturn's atmosphere where it ended spectacularly in cleansing fire.

2017-11-08: Zero-Point Energy Demystified

  • 03:10: But try to drive your car in a dense 1,500 Kelvin atmosphere, and the piston has no reason to rise.

2017-10-19: The Nature of Nothing

  • 12:48: But increase the pressure to around 24 atmospheres, and you can make helium ice at around 1.5 kelvin.

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

  • 13:56: ... our episode on detecting life by observing extraterrestrial atmospheres, Alex asks whether we can observe the atmosphere of Proxima Centauri B. ...
  • 14:10: That method is to watch the effect on the parent stars' light as it passes through the planet's atmosphere.

2017-08-24: First Detection of Life

  • 00:47: ... among others, Carl Sagan, Galileo would measure the spectrum of Earth's atmosphere, take pictures, and look for radio emission during this brief flyby ...
  • 01:35: ... the first-- way we'll spot alien life is by its effect on its planet's atmosphere-- in particular, the chemical content of that ...
  • 01:47: ... you can see these deep dips that result from molecules in Earth's atmosphere absorbing specific wavelengths of light from what would otherwise be the ...
  • 02:12: Apparently, there's water and oxygen in our atmosphere.
  • 02:39: ... equilibrium-- that is, the natural chemical balance that an atmosphere should fall into without something weird like life messing it ...
  • 03:32: Given how quickly methane oxidizes into water and carbon dioxide, there should barely be a single methane molecule in an oxygen-rich atmosphere.
  • 04:15: It's destroyed by solar ultraviolet light in the atmosphere with a half-life of around 50 years.
  • 05:59: If you see water in the atmosphere and the temperature is right, it potentially exists as a liquid on the surface.
  • 07:12: While we need to travel far to get high res pics of an exoplanet, we finally succeeded in taking spectra of their atmospheres without leaving home.
  • 07:26: To be more precise, we analyze the light of a distant star as it passes through the atmosphere of one of its planets.
  • 07:42: ... a tiny fraction of the star's light passes through the planet's atmosphere when this happens, but by carefully subtracting most of the star's ...
  • 08:45: We don't quite have the technology to analyze an Earth-like atmosphere around an Earth-like planet.
  • 08:51: Those planets are just too small and their atmospheres too thin for any current telescope.
  • 09:21: ... seven exoplanets around TRAPPIST-1, assuming they actually have decent atmospheres. ...
  • 10:08: Our first evidence of it is likely to be found in the disequilibria of alien atmospheres.
  • 10:31: Perhaps that answer is already traveling to us in the light of a distant planet's atmosphere calling to us from across spacetime.

2017-08-16: Extraterrestrial Superstorms

  • 04:50: ... Earth, the only source of condensation is water, but the gas giants' atmospheres span such a wide range of temperature and pressure that all sorts of ...
  • 05:21: All of this happens in the troposphere, the densest and innermost layer of the atmosphere.
  • 05:48: Now, the spot itself is quite cold, in fact below freezing, but all of its activity warms the upper atmosphere to 1,600 Kelvin.

2017-07-19: The Real Star Wars

  • 05:29: X-rays are quickly absorbed in the atmosphere.

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

  • 09:52: ... through the galaxy, they may have collected enough dust in their atmospheres to disguise themselves as the younger ...

2017-05-17: Martian Evolution

  • 05:39: What about this pesky lack of a decent atmosphere?
  • 06:01: This is especially true if we eventually terraform Mars because probably whatever atmosphere we build won't be as thick as Earth's.
  • 06:30: Mars's thin atmosphere and lack of an ozone layer also means the surface is bombarded with hard UV radiation.
  • 07:20: These bombard the surface due to the sparse atmosphere and the absence of a protective magnetic field.
  • 13:33: The typical blurring of Earth's atmosphere is one to two arcseconds, which makes it tough.

2017-05-10: The Great American Eclipse

  • 05:58: ... from a specific electron transition in the hydrogen of the sun's upper atmosphere. ...
  • 06:18: What shows up next is the ghostly light of the corona, the sun's outermost atmosphere.

2017-04-19: The Oh My God Particle

  • 00:25: ... at 99.99999999999999999999951% of the speed of light crashed through our atmosphere and streaked across the Utah ...
  • 03:18: So when cosmic rays enter the atmosphere, they're actually traveling faster than the new, lower speed of light.
  • 08:29: Part of the challenge in understanding cosmic rays is that our atmosphere and magnetic field shield the surface of the earth so well.

2017-04-05: Telescopes on the Moon

  • 01:16: See, the moon has essentially no atmosphere.
  • 01:25: Two, Earth's atmosphere blocks all but a few narrow windows of the electromagnetic spectrum.
  • 01:51: ... ultraviolet wavelengths and in the visible range observable within our atmosphere. ...
  • 04:05: An extremely thin atmosphere confers several advantages, but it also has its issues.
  • 04:11: To start with, Earth's thick atmosphere is a powerful buffer against rapid changes in temperature.
  • 05:05: See without an atmosphere there is no erosion of the lunar regolith.
  • 07:20: ... is expensive, heavy, and likely to evaporate in the moon's low pressure Atmosphere Pete Worden, Director of NASA's Ames Research Center and Ermanno Borra ...
  • 08:56: The moon with its thin atmosphere, stable surface, and long nights is an astronomer's dream.

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

  • 04:39: That could be OK for habitability if they have sufficiently thick atmospheres to mix the heat from their sun globally.
  • 06:12: The TRAPPIST-1a's winds may have eroded its planet's atmospheres, just as the sun did with Mars.
  • 06:34: We don't yet know much about what those planet's atmospheres are like.
  • 06:41: All sorts of fascinating nasty compounds can end up in exoplanet atmospheres, all strongly affecting climate temperature and chemistry.
  • 06:50: ... has confirmed that the a, b, and h planets don't have hydrogen helium atmospheres, which means they aren't gassy planets like ...

2017-02-15: Telescopes of Tomorrow

  • 04:03: Space is good for that, because the heat glow of the atmosphere is so bright.
  • 05:13: However, using telescopes within the Earth's atmosphere comes with complications.
  • 05:58: But turbulence in the atmosphere warps those wavefronts.
  • 06:53: ... GMT will shine six powerful sodium lasers 90 kilometers into the upper atmosphere, where their light will produce artificial guide ...
  • 07:23: ... of planets in other solar systems and even to observe the spectra of the atmospheres of some ...

2016-10-19: The First Humans on Mars

  • 03:13: Mars's thin atmosphere and lack of magnetic field make shielding critical, especially for a permanent settlement.
  • 03:20: ... and from the micrometeorites that also pass easily through Mars's thin atmosphere, we really just need a very thick ...
  • 04:37: Mars's atmosphere is 96% CO2, and the rest equal parts nitrogen and argon.

2016-09-29: Life on Europa?

  • 07:50: ... a variety of instruments to sniff out the chemical composition of the atmosphere, surface deposits, and the giant vapor ...

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

  • 05:49: It builds fuel collectors-- maybe orbiters to harvest deuterium or tritium from gas giant atmospheres.

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

  • 08:35: It would ionize the upper atmosphere, resulting in some unfortunate chemistry.

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

  • 04:17: The planet migrates inwards in a similar way to a satellite falling to the Earth due to dragging against the upper atmosphere.
  • 10:11: They've created the most awesome model of Jupiter's weird atmosphere.

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

  • 07:11: Warming oceans and melting permafrost add more CO2 to the atmosphere.

2016-05-25: Is an Ice Age Coming?

  • 05:16: Each year's layer carries bubbles of the Earth's atmosphere from that time.
  • 08:28: Cooler oceans are better at absorbing carbon dioxide from the atmosphere, and so the Earth's natural greenhouse effect is diminished.

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

  • 06:32: The laser propulsion array needs to combine and direct its beams with incredible precision through a turbulent atmosphere.

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

  • 01:18: This puny size means it's hard for Mars to hold onto its atmosphere, for two reasons.
  • 01:35: ... stream of energetic particles from the sun, to whittle away at Mars' atmosphere. ...
  • 01:44: And this is exacerbated by point two, the atmosphere was already only weakly held by Mars' low gravity.
  • 04:35: Both thick atmosphere and strong magnetic field are excellent protection against this stuff.
  • 06:26: Now, the pressure and temperature on the surface, 90 atmospheres and 450 degrees Celsius, will implode and roast you instantly.
  • 07:31: Fortunately, the atmosphere is mostly CO2, so you asphyxiate before you go through any of that.
  • 07:55: You have a think atmosphere above to protect you from bad space radiation.
  • 08:03: ... the interaction of the sun's magnetic field with Venus's think atmosphere actually induces something of a protective magnetic sheath around the ...

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

  • 02:33: Now, beneath the thin atmosphere of ion plasma, a neutron star is a quantum mechanical entity.

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

  • 00:52: And the Chelyabinsk asteroid came in at a shallow angle, so it had lots of atmosphere to burn up in.
  • 01:25: A rock less than 10 meters in diameter vaporizes harmlessly in the atmosphere.

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

  • 07:38: These planets will have atmospheres driven by biotic processes.
  • 07:42: ... we could analyze light passing through these atmospheres, we would see signatures of oxygen, ozone, methane, nitrous oxide at ...

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

  • 13:26: Madhu Sujan Paudel-- hope I pronounced that right-- and gottabweird both asked whether Earth's atmosphere then has tides.

2015-08-05: What Physics Teachers Get Wrong About Tides!

  • 09:24: ... College of Staten Island-- had done a very similar talk about exoplanet atmospheres. ...
  • 09:49: ... down in the description, you'll see a link to her talk about alien atmospheres-- it's very good-- at the NASA Space Apps Challenge, along with a link to ...

2015-06-03: Is Gravity An Illusion?

  • 10:20: When it launches in 2018, will it be able to characterize exoplanetary atmospheres?
  • 11:08: ... systems form, of how proximity to different kinds of stars affects the atmospheres of planets, and so forth-- the prospect for life, ...

2015-05-27: Habitable Exoplanets Debunked!

  • 01:39: A planet with a super-thick atmosphere, for example, could have surface water in a larger orbit than you'd ordinarily expect.
  • 01:56: But to make a more definitive assessment of habitability, actual habitability, for any of these exoplanets, you have to analyze their atmospheres.
  • 02:05: We don't know anything about the atmospheres of any of the so-called Earth-like habitable worlds that get reported in the press.
  • 02:12: In fact, we can't be certain that they even have atmospheres at all.
  • 03:00: ... 186F is just too far away to determine its mass or anything about its atmosphere with current or planned ...
  • 03:22: But the atmosphere is, wait for it, totally up in the air.
  • 03:26: ... Mars, or a carbon dioxide super-greenhouse like on Venus, or it could no atmosphere at ...
  • 03:39: Could we measure properties of their atmospheres and locate a truly habitable world like that?
  • 03:46: You can measure the atmosphere of an exoplanet, but not if that exoplanet is an Earth-sized rocky body in a star's habitable zone.
  • 03:54: ... analyze a planet's atmosphere, you need to isolate the planet's light from that of its star and see how ...
  • 04:12: ... from its star, you can use models to get a rough picture of what the atmosphere is ...
  • 05:23: But unless it is really close or really far, its atmosphere cannot be measured easily, and you can't know whether it really might be habitable.
  • 05:34: ... planet finder, or TPF, a space telescope that could have analyzed the atmospheres of Earth-sized planets in Earth-like orbits around Sun-like like ...

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

  • 09:52: ... altitude, would there be some point near the center of the rim where the atmosphere got so thin that you'd suffocate and there'd be a suffocation ...

2015-04-29: What's the Most Realistic Artificial Gravity in Sci-Fi?

  • 05:27: And it even has radially inward-pointing walls to hold in an atmosphere.

2015-03-18: Can A Starfox Barrel Roll Work In Space?

  • 00:52: When The Arwing is in a planetary atmosphere, a barrel roll is child's play, it's aerobatics 101.
  • 01:21: So in an atmosphere, the maneuver is all about the ailerons.
  • 02:30: Now, on a planet, the clockwise and subsequent counter-clockwise torques required to do this are provided by the atmosphere.

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

  • 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.
  • 07:36: James Roach and a lot of people on the Reddit thread bring up the sulfuric acid in the atmosphere.
  • 07:40: Look, there's not that much sulfuric acid in the atmosphere.
  • 07:43: There's a lot of sulfur dioxide, but the sulfuric acid is a tiny fraction of a percent of the entire Venutian atmosphere.

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

  • 01:49: It also has a thick atmosphere, unlike that wispy layer on Mars.
  • 03:31: It's over 90 Earth's atmospheres.
  • 04:29: The pressure at that altitude also dropped to almost exactly one Earth atmosphere.
  • 04:45: ... at that altitude, the atmosphere is still dense enough for lots of stuff to floae-- like balloons filled ...
  • 04:54: ... in the favorable gravity, and it starts to look like the upper atmosphere of Venus might be the closest thing in the solar system to an Earth-like ...
  • 05:51: Centuries from now, if we learn how to sequester enough carbon out of its atmosphere, we might even be able to plant a flag or two.
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