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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.
  • 11:35: Supernovae, colliding neutron stars and black holes, tidal disruption events when black holes rip apart stars, you name it.
  • 16:23: So any that formed naturally, say in a supernova, may have decayed by now.
  • 16:33: ... heavy elements are produced in supernovae or in colliding neutron stars by the R-process - basically bombarding ...

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

  • 03:36: Those elements eventually find their way into planets, which form from the guts of those stars after they explode as supernovae.

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

  • 18:29: ... could get there. Also some transient phenomena - like supernovae, or cosmic ray ...

2022-09-14: Could the Higgs Boson Lead Us to Dark Matter?

  • 04:26: ... this source of gamma rays from other astrophysical sources like pulsars, supernovae, and things being eaten by black ...

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

  • 06:25: ... constant - the current rate of expansion of the universe, based on supernova explosions over the past several billion years, we get one number for ...
  • 13:27: ... of the expansion rate back billions of years from the current supernova measurements. There are also suggestions that the quintessence field may ...

2022-06-22: Is Interstellar Travel Impossible?

  • 06:26: It was probably created by a past supernova explosion.
  • 06:41: This stuff comes from heavy elements that are fused in the cores of massive stars and ejected in supernovae or in the winds from giant stars.
  • 12:29: These things are accelerated in the monstrous magnetic fields of black holes and supernovae and of the galaxy itself.

2022-06-01: What If Physics IS NOT Describing Reality?

  • 14:22: ... abundance of necessary elements   and there not being too many supernovae. The  galactic habitable zone is defined to be a   ring ...

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

  • 05:11: ... the gas that formed them   was enriched by the same number of supernovae and other explosions. We can measure the heavy element   ...
  • 12:11: ... bout of star formation in about  2 billion years. The accompanying supernova waves   may not be the best thing for life on Earth, but  ...

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

  • 06:28: ... in  massive stars and then spread through the galaxy   in supernova explosions. So a big factor  in determining the galactic habitable ...
  • 07:36: ... and spraying heavy elements into the surrounding  gas in colossal supernova explosions.   The metallicity of the universe began to ...
  • 08:01: ... the galactic bulge grew,   it was wracked by further waves of supernovae. As  Moiya mentioned, having excessive exploding stars   ...
  • 10:48: ... thousand light years from the  center, it expanded inwards as the supernova rates   dropped, and outwards as metallicity increased.  ...
  • 11:12: ... element abundance; the likelihood  of surviving obliteration by supernovae;   and the probability that life could emerge given  the amount of ...

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

  • 00:30: ... structure will be obliterated, gas will be compacted to produce waves of supernovae, and the giant Milkdromeda galaxy will have been ...
  • 08:45: ... and even star and planet destruction  in collisions or supernovae. ...
  • 10:02: ... gas and dark matter interacting to produce waves of star formation and supernovae, settling into spiral structures - just like we see in the real ...

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

  • 00:02: ... possibly so regular where do they come from [Music] do they become supernovae and something something thanks lol from italy so stefania lol to you ...

2021-09-21: How Electron Spin Makes Matter Possible

  • 16:27: ... There was speculation that quasars could be swarms of neutron stars or supernova cascades or even bizarre objects flying at crazy speeds out of the Milky ...

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

  • 00:25: ... form from the dead cores of massive stars,   left over after supernova explosions. We’ve  seen how they look from afar - ...
  • 04:39: ... forged in the core of the star in the   hours before it went supernova - and some of it still survives here at the neutron star ...

2021-08-10: How to Communicate Across the Quantum Multiverse

  • 15:46: ... one possibility is that the partner goes on to explode as a supernova. But the mass transfer onto the white dwarf actually makes this less ...
  • 16:27: ... Persona asks what happens to the star’s magnetic fields after it goes supernova. And then guesses the correct answer - it dissipates into space with the ...
  • 16:58: ... fields have very clear bubble-like structures that come from past supernovae. ...

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

  • 08:29: ... a white dwarf and then slowly add more mass it’ll explode as a type 1a supernova. ...
  • 11:20: ... white dwarfs DO explode then it may well be that many of the type 1a supernovae that we see are NOT from accreting white dwarfs, as originally ...
  • 11:36: ... universe on the largest scales. That’s because observations of type 1a supernovae were how we first discovered the existence of dark energy, and we’ve ...
  • 11:52: ... it turns out that a significant number of those supernovae came from merging white dwarfs rather than accreting white dwarfs then ...
  • 12:16: ... get me wrong, this issue with the supernovae would not make dark energy go away - there’s too much independent ...
  • 13:30: ... electron capture chain reaction may begin - giving us another path to supernova, and a bad end for our highly suspicious little ...

2021-07-21: How Magnetism Shapes The Universe

  • 06:00: The interstellar medium - the space between the stars - is scattered with tiny specks of dust produced in past supernova explosions.
  • 09:21: ... coriolis-induced helical flows, and those flows can also be produced by supernova ...
  • 09:38: Those supernovae may also give us the seeds of magnetic fields that can then be amplified by the galactic dynamo.
  • 10:09: ... blasts accompany every supernova explosion, and these help to compress gas in the path of that explosion, ...
  • 10:17: ... same supernovae are expected to blast their own guts entirely out of the galaxy, which ...
  • 11:15: These can also be accelerated in the magnetic shock-fronts of supernova explosions.

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

  • 03:16: We know black holes form from the remaining cores of the most massive stars, after they explode as supernovae.
  • 03:37: ... can also see the products of the supernova explosions- not so much the black holes produced in those explosions, ...
  • 03:47: ... heavy element abundance tells us there haven’t been anywhere near enough supernovae to give us enough black holes to make up all of dark ...
  • 07:04: Like striking a match, this would ignite a cataclysmic chain reaction, exploding the star as a type 1a supernova.
  • 07:22: But we see too few type 1a supernova and too many neutron stars for this to be a common phenomenon.

2021-03-23: Zeno's Paradox & The Quantum Zeno Effect

  • 13:22: ... microwave background, and in the more modern universe measured with supernovae. ...
  • 14:22: ... could therefore be resolved by finding an error in either the CMB or supernova measurements, but also by finding one of the assumptions in the CMB ...
  • 16:44: Whether it's a full blown existential crisis, or just a little radiating Hubble tension in your neck from staring at too much supernova data.

2021-03-16: The NEW Crisis in Cosmology

  • 03:13: ... of   standard candle - the incredibly bright “type 1a” supernovae that result when a white dwarf   star explodes after ...
  • 03:55: ... One is to double down on the old method - find more type 1a supernova and improve those   distance measures. The other is to find a ...
  • 05:31: ... discoverers of dark energy   has doubled down on the supernova  method. A couple of years ago his   team published a new ...
  • 06:22: ... or the other   if the difference between the Planck  and supernova results is real.   Most people still think that there ...
  • 09:17: ... candles, which in turned   enabled a recalibration of type 1a supernovae - which in turn gave Adam Reiss and team a refined   ...
  • 09:50: ... options that will either to break the   tie between Planck and supernova,  or to confirm that the difference is ...
  • 10:40: ... a Hubble constant in the low 70s - so   in agreement with the supernova guys. But this game is about to take off, with upcoming ...

2021-02-17: Gravitational Wave Background Discovered?

  • 00:00: ... holes and neutron stars have been merging for all of cosmic history and supernovae have been exploding and stellar remnants have been spinning and probably ...

2020-12-22: Navigating with Quantum Entanglement

  • 13:08: ... week we talked about a possible new type of supernova - the black dwarf or iron star supernova, which may be the very last ...
  • 13:23: Kroy H correctly summized there there are still more types of supernova to talk about.
  • 13:47: ... a very massive star collapses after expending its fuel - that’s a type 2 supernova - or the remnant of a lower mass star - a white dwarf - gains extra mass ...

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

  • 00:54: ... forward to one last source of astrophysical cataclysms - a new type of supernova that can only happen at the end of the ...
  • 01:52: ... will undergo catastrophic collapse, and then rebound as a spectacular supernova explosion - a last firework to celebrate the end of ...
  • 06:17: We now know that the end result is either a neutron star or a black hole, accompanied by a powerful supernova explosion.
  • 09:45: ... for some of these iron stars to end on a brighter note - as black dwarf supernovae. ...
  • 11:03: ... that happens, catastrophic collapse should result in a new type of supernova that will only happen in that distant future - a black dwarf ...
  • 12:14: ... we’ve decided to dedicate all 10^3600 years of black dwarf supernovae across the entire end of the universe as a barely-adequate fireworks ...
  • 12:25: And if it turns out that black dwarf supernovae don’t actually exist - well, I can assure you that our gratitude still does.

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

  • 02:40: ... ago, before even Earth formed, when tiny particles of dust from a past supernova found each other in the forming solar system and built up into grains ...

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

  • 07:25: ... - for example using natural particle accelerators like the sun or supernovae or quasars or galactic magnetic fields, which continuously spray the ...
  • 16:54: ... gives you a supernova and leaves nothing behind but a pretty cloud of gas Leandro asks how we ...

2020-08-17: How Stars Destroy Each Other

  • 09:59: A runaway fusion reaction rips through the star, which explodes as a Type 1 supernova.
  • 10:05: Those supernovae are visible not just across the galaxy, but in galaxies across the universe.

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

  • 04:44: A neutron star is what’s left after some massive stars explode as supernovae.
  • 05:01: ... of matter while the rest of the infalling core rebounded causing the supernova ...
  • 10:08: Like I said earlier, a neutron star forms when a star’s core collapses, but most of the material rebounds as a supernova explosion.

2020-06-15: What Happens After the Universe Ends?

  • 18:05: ... is it possible to be devoured by a black hole while being blasted by a supernova, and frozen by the heat death of the universe all at the same ...

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

  • 00:00: ... plane to the crowd but oh it is gold leaf and goals was forged in some supernova well emerging of nutrients neutrons to see you learn a lot living in ...

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

  • 00:47: ... searing hot clouds of gas, massive stars right on the edge of going supernova, and some of the most energetic radiation in the ...
  • 03:56: It goes like this: atomic nuclei - mostly lone protons - can get accelerated to extreme energies, typically in supernovae or other cataclysmic events.
  • 05:42: It’s estimated that the energy contained in this ocean of electrons is equivalent to that released by 100,000 supernova explosions.
  • 06:21: I mentioned an energy of 100,000 supernovae - well that’s actually a serious option.
  • 06:36: Believe it or not, it’s not so uncommon for astronomers to witness storms of supernova explosions raging across a galaxy.
  • 07:09: ... Bubbles, but starbursts are always accompanied by an enormous number of supernova explosions because the most massive stars produced in the starburst die ...
  • 07:25: ... shock waves created by the supernovae from a starburst in the Milky Way could literally punch a hole through ...
  • 07:43: All of those supernovae would have had to leave remnants behind - neutron stars and black holes.
  • 10:17: This starburst and the subsequent supernova barrage smooths out the energy in the bubbles.
  • 12:21: ... researchers believe that the starburst and accompanying supernova cascade that may have helped forged the Fermi Bubbles would have been ...

2020-01-13: How To Capture Black Holes

  • 00:24: ... new things. When we figured out how to see in radio waves quasars and supernova remnants lit up the sky, When we learned to see in neutrinos the core of ...

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

  • 05:49: In our modern universe, black holes are made when the most massive stars explode as supernovae.

2019-12-02: Is The Universe Finite?

  • 02:06: ... observed today - particularly the modern expansion rate determined from supernova ...

2019-10-15: Loop Quantum Gravity Explained

  • 14:59: We do see this effect in the light from gravitationally lensed quasars and supernovae.

2019-06-17: How Black Holes Kill Galaxies

  • 07:21: ... self-limiting process because intense starbursts leads to intense supernova activity which could also heat or expell gas and limit further formation ...

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

  • 00:34: ... and that elements heavier than iron were synthesized in the following supernova explosion that latter process is well understood the stars dead core ...
  • 02:47: ... elements exist but their source doesn't seem to be supernova explosions one of the proposed alternatives shot to prominence last year ...

2019-05-16: The Cosmic Dark Ages

  • 02:52: ... of their electrons once again. They also died quickly, and their violent supernova explosions contributed to reionization. They also scattered the first ...

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

  • 10:58: ... Cosmic Microwave Background, in the baryon acoustic oscillations and in supernovae - We've talked about all of these thing ...

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

  • 01:38: They were measuring the distances to supernovae to track the changing size of the expanding universe.
  • 03:54: The expansion history of the universe is typically measured using the same type of supernova observations that first discovered dark energy.
  • 04:14: ... our telescope, we can figure out pretty precisely how far away the supernova was when it ...
  • 04:25: Type 1a supernovae are what we call standard candles – objects of known brightness that can be used to find distance.
  • 04:33: If we have lots of supernovae at different distances when we have a set of rulers spanning both time and space.
  • 04:40: The most distant supernova we’ve seen is so far away that its light has been traveling to us for around 75% of the age of the universe.
  • 05:21: It may be an issue with how we determine the starting conditions of the universe, or it may be our measurements of supernovae.
  • 05:44: ... reliable than our measurement of its subsequent expansion history via supernovae. ...
  • 05:55: Part of the reason for that is that supernovae aren’t bright enough to see through ALL of cosmic history.
  • 06:03: We miss the first 25%, and we’ve found too few supernovae over the first 50% of cosmic time.
  • 09:46: Fortunately there are a LOT of quasars out there – far more than known supernovae.
  • 12:59: In fact there are alternative ideas that try to resolve the conflict between the CMB, supernova, and now the quasar results.
  • 13:27: ... a systematic problem with the way supernova and/or quasar distances are determined, or even an issue with the cosmic ...

2019-02-07: Sound Waves from the Beginning of Time

  • 11:00: Dark energy was first discovered by using distant supernovae as distance measurements- to track the rate of expansion of the universe.
  • 12:06: The baryon acoustic oscillations agree with and confirm what we measure using supernovae distances- The expansion of the universe is accelerating.

2019-01-24: The Crisis in Cosmology

  • 04:34: Supernovae can be seen much further,...
  • 04:38: ...and type 1a supernovae are the key.
  • 04:59: ...astronomers were using these supernovae to better nail down the Hubble constant.
  • 05:21: A big part of his work is to improve the calibration of type 1a supernovae as standard candles.
  • 05:27: Riess's Supernovae H0 for the Equation of State project, - SHOES -,...
  • 05:32: ...uses the Hubble Space Telescope to match old supernovae observations...
  • 05:41: ...all past supernovae distances also improve.
  • 06:37: ...or there is a big problem, with either our supernova measurements...
  • 06:47: ... observation I'm referring to is far more reliable than Cepheids and supernovae. ...
  • 09:53: ...compared to the supernova result of 73.5 ± 1.7.
  • 10:20: This discrepancy first emerged in 2016, when Riess's new calibration of the supernova-derived H0...
  • 10:35: ...and independent methods have been used to calibrate the supernovae as standard candles.
  • 10:57: ...in either the supernova or Planck measurements.

2019-01-09: Are Dark Matter And Dark Energy The Same?

  • 01:52: Observations of distant supernovae tell us that the expansion of the universe is accelerating.
  • 10:23: First, does it predict an expansion history that fits the supernova observations that originally discovered dark energy?
  • 10:31: Those supernova results suggest a universe that started expanding rapidly and then slowed down due to the gravity of matter – mostly dark matter.
  • 10:57: That’s hard to fit to the supernova data.
  • 11:25: But a constant or near-constant expansion rate definitely does not fit the supernova data.

2018-11-14: Supersymmetric Particle Found?

  • 03:52: ... Supernova explosions, gamma ray bursts, black hole magnetic fields are all ...
  • 09:56: ... the Earth with enough high energy neutrinos, for example from a supernova explosion, and at least some of the ultra high energy ones could make it ...
  • 10:05: In fact, one of the two events may have been associated with a distant supernova that was observed around the same time and location.
  • 10:13: The probability of a chance association with a supernova is around 3%, so it's unlikely but it does happen.
  • 10:21: On the other hand, the supernova in question wasn't nearly bright enough to make even one earth penetrating ultra high energy neutrino likely.
  • 10:33: The other event wasn't associated with any supernova or gamma ray burst.

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

  • 11:05: ... of weak gravitational lensing in distant galaxies, and see more distant supernovae, monitoring more distant quasars for their ...

2018-05-09: How Gaia Changed Astronomy Forever

  • 07:58: And it'll identify 100,000 supernova.

2018-04-25: Black Hole Swarms

  • 02:11: Black holes form when the most massive stars end their lives in spectacular supernova explosions.
  • 02:37: Even after blowing off most of their mass in a supernova, these black holes are still heavier than most stars.
  • 09:26: Majestic potato asked, whether a supernova can produce gravitational waves detectable from Earth?
  • 09:36: The trick is that supernova can't be spherically symmetric.
  • 09:52: So if the explosion of a supernova is concentrated, say, more on one side, then LIGO could potentially see the resulting gravitational waves.

2018-02-21: The Death of the Sun

  • 01:09: The most massive stars live only for hundreds of thousands to millions of years, and die in spectacular explosions called supernovae.

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

  • 00:35: ... deal with their effects, like the damage caused by gamma-ray bursts and supernovae. ...
  • 01:17: ... but let's start with the one that could happen any time-- a supernova or gamma-ray burst frying our ...
  • 02:34: As many of you know, a supernova is the explosion that follows the catastrophic collapse of a massive star at the end of its life.
  • 02:58: Any planet within a few tens of light years of a supernova is in trouble.
  • 08:38: Gamma-ray bursts are much less common than regular supernovae.
  • 08:42: And in fact, regular supernovae can do just as much damage as a GRB.
  • 08:46: However, for a supernova to produce the same effects, it needs to be much closer, within 20 to 30 light years.

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

  • 01:05: ... is in spotting changes in the night sky, spotting things like comets and supernovae or monitoring variable ...
  • 01:48: Supernovae are also fair game for amateurs.
  • 01:57: ... there are a number of supernova-hunting amateurs, but perhaps the most impressive is Tim Puckett's effort out of ...
  • 02:05: His Supernova Search program has found well over 300 supernovae, contributing to many scientific papers.
  • 02:51: Fair warning, though, if you want your own supernova hunting program, you'd better be ready to spend some money.
  • 03:53: ... example, spotting supernovae or looking for gravitational wave signals in LIGO and finding planets ...

2017-09-20: The Future of Space Telescopes

  • 13:25: And if not merging neutron stars, then it was likely a supernova explosion.

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

  • 01:15: LIGO was supposed to also detect some other crazy stuff like certain types of supernova explosion and the merger of binary neutron stars.
  • 01:54: When a massive star ends its life in a supernova explosion, it leaves behind an ultra dense core.
  • 06:58: Most are believed to result from supernova explosions.
  • 08:03: We rarely see supernovae from this galaxy type because their most massive stars have long since exploded to leave neutron stars and black holes.
  • 08:55: It definitely happens in supernova explosions, which for a long time were thought to be the primary source of heavy elements.

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

  • 00:13: The resulting swarms of supernova explosions enriched the universe with the first heavy elements and lots of black holes.
  • 01:01: ... in the cores of earlier generations of stars-- stars that exploded as supernovae, and spread their element-enriched guts through the galaxy, long before ...
  • 05:33: With masses that high, all population three stars would have gone supernova while the universe was still in its infancy.
  • 08:03: ... that there were violent waves of star formation followed by cascades of supernova explosions, ripping through the first ...

2017-04-19: The Oh My God Particle

  • 06:10: For lower energy cosmic rays, it's believed that many, and perhaps most, come from supernova explosions within our galaxy.

2017-02-15: Telescopes of Tomorrow

  • 08:58: It will be easier to find new supernovae, the explosive deaths of stars which, among other things, will improve our understanding of dark energy.

2017-01-25: Why Quasars are so Awesome

  • 07:54: Waves of star formation, followed by waves of supernovae.
  • 09:02: Galaxies had formed, but were no longer wracked by supernovae.

2016-11-16: Strange Stars

  • 02:07: The rest of the in-falling star collides with the new neutron star and ricochets outwards in the most powerful explosion in the universe, a supernova.
  • 08:00: ... all, the pulsar in the Crab Nebula was also observed as a supernova by Chinese astronomers in 1054, except something was weird in the case ...
  • 08:54: Then there are supernovae that appear way too bright and last too long.
  • 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.
  • 09:17: ... still haven't found the expected neutron star at the location of the supernova. ...

2016-11-09: Did Dark Energy Just Disappear?

  • 00:32: They discovered this by watching for the explosions of Type 1-A supernovae.
  • 01:11: ... energy." The finding led to a shared Nobel Prize for the leaders of the supernova hunter teams, Adam Riess, Brian Schmidt, and Saul ...
  • 01:40: Because another team has just announced a new analysis of updated supernova data.
  • 02:26: ... a paper titled "Marginal Evidence for Cosmic Acceleration from Type IA Supernovae." It appeared in the prestigious Nature journal, and that helped it get a ...
  • 02:43: As with the initial discovery of dark energy, these scientists used Type 1-A supernovae to track the expansion history of the universe.
  • 05:32: So the new result doesn't give a high enough significance from the supernova data alone.
  • 05:44: ... or lower for a positive cosmological constant based on that early supernova data ...
  • 06:00: So why did anyone pay any attention? Because they didn't consider the supernova data alone, and nor should we.
  • 07:28: Those blue ovals represent the ranges of combinations of matter and dark energy that are consistent with the new supernova measurements.
  • 08:07: ... if we consider the supernova data by itself, represented by these contours there appears to be a ...
  • 08:52: That alone rules out the region of the supernova results that suggests there's no dark energy.
  • 08:58: Now this was known in the late 90's, which is why the first supernova results were taken seriously.
  • 10:24: That little region where the supernova and CMB results overlap represents the most likely combination of dark energy and matter.

2016-10-19: The First Humans on Mars

  • 10:42: Those seeds may have been from the very first generation of supernovae, near the beginning of the universe.

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

  • 08:30: Of course, regular black holes from supernovae can, and perhaps have, done that.

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

  • 03:28: But in the case of a big asteroid impact or a nearby supernova, it could come with so little warning that we might not have time to do much about it.
  • 08:25: A supernova explosion within 30 light years would destroy the ozone layer, leading to a horrible hard ultraviolet bath and the worst sunburn ever.
  • 08:40: For example, a huge amount of smoggy nitrogen oxide would blanket the planet, causing a supernova winter.
  • 08:47: Fortunately, we know for sure that there are no stars ready to go supernova within any dangerous distance.
  • 08:58: ... a very massive star goes supernova, the resulting collapse of the core into a neutron star, or black hole, ...
  • 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: ... and start colonizing the galaxy beyond the 30-light-year range of a supernova and beyond the width of a typical gamma ray burst death ...

2016-07-20: The Future of Gravitational Waves

  • 04:54: We should eventually see mergers between two neutron stars or a neutron star and a black hole, as well as supernova explosions.

2016-05-18: Anti-gravity and the True Nature of Dark Energy

  • 01:12: We know this, because we've mapped its past expansion history using distant supernovae.

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

  • 11:03: ... sort of luminosity reference point before we can start using white dwarf supernovae or Type 1a supernovae, the standard ...
  • 11:17: We need to figure out the luminosities for a good number of these supernovae independently, before we can start using them as standard candles.
  • 11:25: We do that by finding independent distances to white dwarf supernovae in nearby galaxies.
  • 11:33: ... standard candle, to get an independent distance to the galaxy in which a supernova ...

2016-04-27: What Does Dark Energy Really Do?

  • 03:42: ... a very special type of supernova that's both spectacularly bright and for which we can figure out very ...
  • 03:51: It's a type Ia or white dwarf supernova.
  • 04:04: When the star reaches a critical mass, a runaway fusion reaction obliterates the star as a supernova.
  • 04:24: When you catch a white dwarf supernova, you know its distance and redshift.
  • 05:46: ... also flip this logic and say that for a given redshift, we would expect supernovae to be bright or closer in a high-density, recollapsing universe and ...
  • 06:03: ... separate teams of astronomers spent years catching white dwarf supernovae exploding in galaxies billions of light years away to measure the past ...
  • 06:32: Or conversely, the supernovae were fainter than you'd expect, even for a universe that has no matter in it at all.
  • 06:41: That means the expansion rate of the universe has actually sped up, accelerated, while that supernova light was traveling to us.
  • 09:19: That's what we see in our white dwarf supernova measurements.

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

  • 11:35: ... to know where the actual elements in our bodies came from and where the supernovae that produce those elements and their remnants are ...
  • 12:28: And it was blasted away by supernovae from the most massive stars it produced.
  • 12:35: ... that form the Earth and that form you may, in part, be from those supernovae, but more will be from previous generations of stars that enriched that ...

2016-04-06: We Are Star Stuff

  • 00:00: ... forged in violent stellar alchemy and spread through the galaxy in past supernovae. ...
  • 07:24: ... star and ricochet back in the largest explosion in the universe, a supernova. ...
  • 07:49: All of the main ingredients of your own body were fusion shells in past supernovae.
  • 08:06: Until recently, it was thought that most naturally occurring elements heavier than iron were produced in that supernova explosion itself.
  • 08:42: But was that explosion necessarily a typical supernova?
  • 09:04: This is also seen as a supernova, and it also laces the galaxy with heavy elements.
  • 09:16: ... including a lot of the gold in the universe, were formed not in a supernova, but in the collision of two neutron ...

2016-03-30: Pulsar Starquakes Make Fast Radio Bursts? + Challenge Winners!

  • 01:11: ... various types of cataclysmic events, like colliding stellar remnants, supernovae, neutron stars collapsing into black holes, crazy stuff like ...

2016-02-24: Why the Big Bang Definitely Happened

  • 05:46: ... star formation but poor in the heavy elements released by generations of supernovae. ...

2016-02-17: Planet X Discovered?? + Challenge Winners!

  • 07:12: ... the same time, supernovae that are moving away from us due to the expansion of the universe appear ...

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

  • 04:14: We'll also spot supernova explosions that produce neutron stars.
  • 06:13: ... holes and neutron stars, as well as the formation of neutron stars and supernova ...

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

  • 01:18: Just wait a few million years for the supernova.
  • 02:09: The collapsing outer shells ricochet off this impossibly dense nugget in a supernova explosion, enriching the galaxy with juicy new elements.

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

  • 09:48: ... the epoch of life in a universe abundant in the rich resources of past supernova explosions, but after the violence of the starburst and quasar ...

2015-10-22: Have Gravitational Waves Been Discovered?!?

  • 03:16: ... in-spiraling just before merger, or gravitational catastrophes like supernova explosions or collisions between giant black holes-- these make g-waves ...
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