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

  • 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: ... years - although we do encounter it in nature because it’s created when cosmic rays hit nitrogen nuclei in the ...

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

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

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

  • 03:14: So dark matter detectors consist of huge tubs of liquid or massive chunks of crystal, placed deep underground to avoid cosmic rays.

2022-06-22: Is Interstellar Travel Impossible?

  • 03:50: And that’s to say nothing of cosmic rays - particles moving fast enough to kill all on their own.
  • 12:17: But none of this helps against the other type of radiation - cosmic rays.
  • 12:35: ... radiation dose from cosmic rays is lower than that of the interstellar gas - it’s not instantly lethal, ...
  • 12:48: However it’s harder to protect against cosmic rays because they hit the ship from all directions.
  • 12:55: If you manage to accelerate to 80 or 90% light speed then most of the cosmic rays will hit from in front, and then your windshield protects you.
  • 13:32: ... years, shielding against the interstellar medium, micrometeoroids and cosmic rays will have to get more ...

2021-10-05: Why Magnetic Monopoles SHOULD Exist

  • 13:24: ... also look for magnetic monopoles coming from space - typically using cosmic ray observatories - or contributing to the Earth’s magnetic field - and in a ...

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

  • 16:27: ... particles to even higher energies. This is believed to be one source of cosmic rays that reach the earth. The magnetic fields then go on to add to the ...

2021-07-21: How Magnetism Shapes The Universe

  • 11:08: Electrons and atomic nuclei can be accelerated in this magnetic field to high energies - into what we call cosmic rays.
  • 11:20: But the most energetic cosmic rays are accelerated by the strongest magnetic fields.
  • 11:47: Those fields grab particles of matter and accelerate them to incredible energies, flinging cosmic rays out into the universe.

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

  • 02:55: ... in the chips and dents on its surface, it recalls being hit by cosmic rays in the melt-tracks through its embedded glassy grains, and those grains ...
  • 03:52: Well, more collisions building it up or breaking it down, more cosmic ray hits, that sort of thing.
  • 06:13: Over time the rock changes - new clumps might hit the rock and become embedded, cosmic rays leave their mark, etc.
  • 06:34: ... particles with all of its detailed structure mysteriously in place - cosmic ray tracks, embedded clumps, bumps and scratches, ...
  • 06:45: ... those features get erased one by one - cosmic rays happen to pass through in exactly the right way to erase their tracks, ...
  • 08:02: Let’s say it’s a final cosmic ray strike.
  • 08:06: ... its entire future, because there’s no way you could predict that future cosmic ray strike with the internal structure of the asteroid ...
  • 08:18: Before the cosmic ray strikes, the asteroid has no knowledge of the incoming impact.
  • 08:22: We would say that the rock and the cosmic ray are not correlated in any way.
  • 08:30: Even without access to the cosmic ray, the rock now holds information about the ray, and the ray holds information about the rock.
  • 08:48: It has this inexplicable scar running through it that is now perfectly removed by a passingly cosmic ray.
  • 08:56: That means that before the cosmic ray hit, the asteroid was correlated with its environment.

2020-10-05: Venus May Have Life!

  • 07:00: You might get some produced by lightning strikes in the cloud layers, or by cosmic rays hitting the upper atmosphere.

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

  • 07:41: ... these ultra-high energy cosmic rays are rare, and to reliably detect a new particle we need to watch the ...

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

  • 00:00: ... so this is you know looking for uh you know looking for like cosmic ray cosmic rays gamma gamma ray bursts you know uh uh but also ...

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

  • 05:43: ... in nature - for 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?

  • 09:21: ... virus has survived being bathed in the equivalent of 250 years of cosmic rays, simulated by an intense shower of energetic ...
  • 09:55: Some viruses do have the remarkable ability to sort of reassemble their genetic code after irradiation by UV or cosmic rays.
  • 10:52: ... a barrier of rock or ice will shield against ultraviolet light and cosmic rays. ...

2020-04-22: Will Wormholes Allow Fast Interstellar Travel?

  • 15:35: ... within a galaxy, the space between the stars is full of gas, radiation, cosmic rays, and dust. When I say "full", I mean it's everywhere - but its very ...

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

  • 03:52: This is mostly from cosmic ray interactions with the interstellar medium.
  • 04:06: These “cosmic rays” can then collide with nuclei in the gas between the stars - again, mostly the protons of hydrogen.
  • 04:49: The gamma rays produced by neutral pion decay from these cosmic ray collisions tend to drop off in intensity towards higher energies.

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

  • 08:25: ... Carbon-14 exists on the surface of the earth because it’s produced when cosmic rays hit nitrogen in the atmosphere, resulting in a constant proportion of ...

2019-09-16: Could We Terraform Mars?

  • 02:15: And of course Earth’s atmosphere protects us from harmful cosmic rays and the most dangerous ultraviolet radiation from the Sun.

2019-06-17: How Black Holes Kill Galaxies

  • 14:00: But you might see the result of it's decay a particular spectrum of radiation and cosmic rays.

2018-12-20: Why String Theory is Wrong

  • 14:12: There's a hint from cosmic rays, we talked about it earlier.

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

  • 00:37: ... UV radiation of a star interstellar space is thick with energetic cosmic rays near light speed atomic nuclei as well as x-rays and gamma rays ...

2018-11-21: 'Oumuamua Is Not Aliens

  • 07:13: ... has been fused into a crust by millennia of exposure to interstellar cosmic rays. ...

2018-11-14: Supersymmetric Particle Found?

  • 04:02: These are cosmic rays.
  • 04:05: The highest energy cosmic rays can have energies around a billion times that of the LHC.
  • 04:11: Unfortunately, for particle physics experiments cosmic rays at these energies are extremely rare.
  • 04:17: So it's not surprising that we haven't seen supersymmetric particles in our cosmic ray observations yet, or have we?
  • 04:37: It's a cosmic ray experiment of a very special sort.
  • 04:40: In fact, it's a cosmic ray detector disguised as a neutrino detector disguised as a radio antenna disguised as a hot air balloon.
  • 04:50: When ultra high energy cosmic rays travel through space, they bump into the photons of the cosmic microwave background.
  • 05:01: Those cosmic rays lose energy to the CMB, which is partly why the most energetic cosmic rays are so rare here on earth.
  • 05:09: But in those interactions, cosmic rays can create extremely high energy neutrinos.
  • 05:20: So detecting the highest energy neutrinos allows us to learn about the cosmic rays that produced them.
  • 06:08: ... the very highest energy neutrinos, the ones that are produced by cosmic ray interactions with the ...
  • 06:55: That allows it to sort out neutrino radio flashes from the flashes produced by other cosmic rays coming in from above.

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

  • 02:46: ... so ultraviolet, x-rays, gamma rays, and near-light-speed particles-- so cosmic rays-- into the surrounding interstellar ...

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

  • 09:19: Only a few years after Dirac wrote down his equation in 1928, the positron, the anti-matter electron, was spotted in cosmic rays by Carl Anderson.

2017-05-17: Martian Evolution

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

2017-04-19: The Oh My God Particle

  • 00:00: ... Long before the God particle, there is the Oh-My-God particle, a cosmic ray vastly more energetic than had ever been seen or was even thought ...
  • 00:13: These ultra-high energy cosmic rays still perplex scientists.
  • 00:51: ... an early experiment by the University of Utah to spot the highest energy cosmic rays in the ...
  • 01:03: ... analyzing the Fly's Eye data calculated that the cosmic ray responsible for this particular flash must have had a kinetic energy of ...
  • 01:35: In fact, cosmic rays of that energy was supposed to be impossible.
  • 01:40: Let's talk about cosmic rays for a second.
  • 02:42: Cosmic rays had been discovered.
  • 02:44: ... of the Oh-My-God particle, we've come a long way in the art of catching cosmic rays. ...
  • 03:03: For lower energy cosmic rays, one approach is to look for their Cherenkov radiation.
  • 03:09: All cosmic rays are traveling at pretty close to the speed of light, but that's the speed of light in a vacuum.
  • 03:18: So when cosmic rays enter the atmosphere, they're actually traveling faster than the new, lower speed of light.
  • 03:31: Higher energy cosmic rays tend to obliterate themselves several kilometers above the ground in massive collisions with nuclei of air molecules.
  • 04:02: ... debris, the collision that produced them and the nature of the original cosmic ray can be ...
  • 04:12: Several facilities around the world are devoted to catching cosmic rays.
  • 04:16: For example, the Pierre Auger Observatory in Argentina monitors a region around 3,000 square kilometers for high-energy cosmic rays.
  • 05:01: By now, we have a pretty good census of the types of cosmic rays that tend to hit the Earth.
  • 05:13: But about 1% of cosmic rays are heavier nuclei, as heavier as iron.
  • 05:54: To accelerate a particle to the energies of cosmic rays, you need a particle accelerator.
  • 06:10: For lower energy cosmic rays, it's believed that many, and perhaps most, come from supernova explosions within our galaxy.
  • 06:29: The higher the energy of the cosmic ray, though, the more likely it is to have originated from outside our galaxy.
  • 06:36: The exact sources of these so-called extra galactic cosmic rays are more mysterious.
  • 06:47: The most ridiculous cosmic rays, like the Oh-My-God particle, shouldn't exist at all.
  • 07:11: ... Cosmic rays with energies over 5 times 10 to the power of 19 electron volts, about 8 ...
  • 07:27: For years, it was thought that no cosmic ray could exceed it, except that the OMG particle was six times more energetic.
  • 07:36: Only a very small number of these extreme energy cosmic rays have been seen since the OMG particle.
  • 08:15: It's still a mystery exactly what produces these extreme cosmic rays and how close to us the sources are.
  • 08:22: For cosmic ray astrophysicists, there's a giant invisible particle accelerating elephant in the room.
  • 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.
  • 08:39: ... strange flashes of light, which may be due to Cherenkov radiation from cosmic rays passing through their eye's vitreous humor, or from the particles ...
  • 09:00: Along with solar outbursts, cosmic rays are one of the most serious obstacles to manned interplanetary travel.
  • 09:07: ... we figure out the origins of these particles, cosmic ray astronomy is becoming an increasingly powerful tool for investigating ...
  • 09:20: ... highest energy cosmic rays, like the Oh-My-God particle, generate collisions far more energetic than ...
  • 09:30: Studying cosmic rays may crack open the mysteries of both the largest and the smallest scales of space time.

2017-01-25: Why Quasars are so Awesome

  • 07:59: These forming galaxies were continuously blasted with energetic radiation and cosmic rays.

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 ...

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

  • 06:23: Everything will have to withstand tens of thousands of G's of acceleration and impact from interstellar dust or cosmic rays.

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

  • 04:29: See, space is flooded with extremely energetic solar radiation and cosmic rays.

2015-06-17: How to Signal Aliens

  • 02:31: ... repeated flashes to know that you don't have a false positive from a cosmic ray or ...
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