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10:00And they were originally detected using decay of radioactive material here on Earth. Right, so who cares? Or why does it matter that we detect neutrinos that are coming from space? This is the big leap that is central to this particular Nobel Prize. So right after Cowan and Reines detected the neutrino, it was immediately understood that it would be an ideal astronomical messenger because it's electrically neutral. So it doesn't get messed around by magnetic fields. And it's only subject to weak interactions or gravitational interactions. Gravity doesn't really move stuff around all that much. It's weak. To be perfectly honest, because the neutrino especially, it's weak and the neutrino is like near
10:44massless. So it's just gonna like go through. I mean, it can still move around because of the curvature of space-time, but not by a lot. And it's not really interacting with other types of matter. And so it could give us a sense of what's happening in astronomical sources because it's a direct line of sight. Okay, that's interesting. And the first time that this was actually discovered was in 1987 by two Nobel Prize winners, Davis and Koshiba. They were awarded the Nobel Prize in 2002 for pioneering contributions to astrophysics, in particular, the detection of cosmic neutrinos. These guys are the first to detected cosmic neutrinos. What they did was detect neutrinos from a very significant event, Supernova
11:291987A. On the right-hand side, that's a picture of the Magellanic Cloud, which is a kind of dwarf galaxy that's orbiting the Milky Way. In 1987, a star went Supernova in that cloud. That's really nice because it's really close to us. It's not in the Milky Way. If it was too close, we'd be freaked out. But this is just far enough that you see that central really bright star that's like outshining almost the entire galactic core over there. That is a new star that wasn't there like a week before. That's so unbelievable. You could see it with your naked eye. It was a new star that had formed. People were traveling to the Southern Hemisphere to see this thing. And believe me, had I been alive and had the ability, I would have gotten on a flight to see
12:13this thing with my naked eye. I mean, this is incredible. That's a Supernova. That's the light coming from it. These two detected the neutrinos that came from that explosion. And that was the first time that we were like, "Oh, so we can actually do this. "We can do neutrino astronomy." Right. It's a pathway by which to observe, usually we use photons to observe or other aspects of the electromagnetic spectrum to observe what's happening in space, to create a map. What we're saying is there's another way to do so. And it happens to be that neutrinos are this other vector for mapping the universe around us. Exactly. Is that kind of the right way to think about it? Okay. That's exactly right. And those particular neutrinos from the Supernova 1987A, those were on the order of mega
12:58electron volts. So that's 10 to the six, like a billion, or no, a million electron volts. Mega is a million, a million electron volts. Pretty big. Yeah. This year, the Nobel Prize recognizes the discovery of peta electron volt energies, 10 to the 15, okay? 10 to the 15 electron volts. A tera electron volt is a trillion electron volts. A peta electron volt is a thousand trillion electron volts. This thing is insane, and it's only possible because of an observatory like IceCube, okay? The reason to pursue these particles comes from a century-old mystery because we know they
13:39exist. These high energy events exist. It's about cosmic rays. Cosmic rays were first discovered in 1912 by Hess. He was the Nobel Prize winner in 1936. He got on a balloon, literally, and detected an excess of charged particles in the upper atmosphere coming from extraterrestrial origin. Dude, physicists back in the day-- Right, we're really putting their, it's gumshoe work out in the field. That's fun. Isn't that hilarious? Yeah, that's quite fun. Right, and so these cosmic rays, we'd figured out they're mostly protons and charged atomic nuclei that are arriving from space.
14:20And some of these cosmic rays reach energies of 10 to the 20 electron volts, okay? That's far beyond what anything on Earth that we've built can do, okay? CERN is at about 10 to the 12. This is 10 to the 20. That's eight orders of magnitude above. So that's like 10, no, 100 million times more energy per particle than CERN, okay? That's not a joke because CERN is like really kind of the limit of what we can do right now, okay? There are proposals for larger ones, but even then you're adding like maybe an order of magnitude. Right, not it. And it's like hard to do that, okay?