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8:01at these scales. And so we need to expand what we're looking at in order to capture just more clarity. Yes. And understanding what what >> we want to be sensitive to that correct part >> of the of the spectrum. Right. That makes sense. >> And so that's where these little red dots come in. And they're literally called little red dots. Okay. Weird thing about them is they they show up all over the p place about 600 million years to 800 million years after the Big Bang, but then they vanish out of existence 1.5 billion years after the Big Bang. And we don't see any of them. >> Interesting. >> It's kind of like dinosaurs where like dinosaurs were alive for, you know, 300 million years to 65 million years before us and then they're just gone.
8:42>> So it's kind of these little red dots are like dinosaurs from the early universe that are no longer there in any nearby galaxies. >> Interesting. >> So it's very weird. Right. >> That is curious. >> The other thing about them is they're really small. Okay. They're really, really small. If you look on the right hand side, on the left hand side we've got one of the JWSD deep fields and on the right hand side we have a closeup of one of these red dots. And you if you look really closely, that red dot has a sort of hexagonal hue around it. That hexagonal hue is an artifact of the James Webb Space Telescope's design because >> the James Web has a primary mirror and then a secondary mirror that sort of the
9:23light comes in primary goes to the secondary and then goes to the detector and the scaffolding that is holding up that secondary mirror has three sort of rods that hold it holds it up. So those rods are going to cause something called defraction spikes. They're just artifacts of the fact that the secondary mirror has these three rods holding it up. In the Hubble, there's four. >> Mhm. >> And so you see for the Hubble Hubble photographs, the defraction spikes are >> Yeah. Right. >> in diamond shape. >> But in the James Web, they'll be in hexagonal shape. >> Makes sense. >> Okay. So, but the fact that we're seeing
10:03those diffraction spikes for those little red dots means that they're localized point sources. And we can actually calculate how big they are and they'd be about 150 to 500 light years across. That's really light light years across. >> Years, >> right? The Milky Way is on the order of 100,000 light years. >> Okay. >> Okay. The Milky Way is much bigger >> than these things by a factor of 100 to a thousand. >> Okay. >> So, perhaps they are just like black holes. This is the first clue that maybe they're black holes. They're really compact objects, right? Um they have a lot of activity and a lot of mass. So >> yeah, >> seems like a black hole. >> Okay, so if it's a black hole, we'd like to calculate its size,
10:44>> right? >> Okay. How do we calculate a black hole size? Well, in the Milky Way, the way we calculated the black hole size is we had Andrea GZ from UCLA. She watched the black hole for about 20 years and charted the path of stars that were nearby. And then you just do Newton's laws and you figure out how big is the compact object on the inside. Now, if we've got a black hole