WEBVTT FILE 1 00:00:05.505 --> 00:00:05.772 Yeah. 2 00:00:05.772 --> 00:00:09.476 So we found an individual star, which is the most distant 3 00:00:09.476 --> 00:00:12.512 individual star that has been found thus far. 4 00:00:13.580 --> 00:00:16.316 So normally when we look at very distant objects, 5 00:00:16.316 --> 00:00:19.419 what we're seeing is the light from an entire galaxy. 6 00:00:19.419 --> 00:00:21.888 So millions of stars all blended together, 7 00:00:22.622 --> 00:00:25.892 and we've been able to see those out to even farther distances. 8 00:00:25.892 --> 00:00:31.831 But in this case, thanks to a very massive cluster of galaxies in the foreground, 9 00:00:32.499 --> 00:00:37.203 the light from this one star has just been very, very highly magnified. 10 00:00:37.837 --> 00:00:40.140 So we're able to see this single star 11 00:00:41.141 --> 00:00:43.309 at a much greater distance. 12 00:00:43.309 --> 00:00:47.047 So it's when the universe was less than 1 billion years old. 13 00:00:47.047 --> 00:00:50.216 So we're looking nearly 13 billion years into the past 14 00:00:50.216 --> 00:00:52.419 when we look at this object 15 00:00:56.122 --> 00:00:56.456 Yeah. 16 00:00:56.456 --> 00:00:59.325 So it's thanks to two things, really. 17 00:00:59.325 --> 00:01:02.829 So we have, first of all, the incredible power of the Hubble Space Telescope 18 00:01:02.829 --> 00:01:05.698 that's something that you really need to be able to see something like this 19 00:01:06.066 --> 00:01:10.437 and then combine that with an additional telescope in space. 20 00:01:10.437 --> 00:01:13.540 So through something called gravitation lensing, 21 00:01:14.641 --> 00:01:15.975 a very massive 22 00:01:15.975 --> 00:01:19.913 cluster of galaxies actually bends the light from the background object. 23 00:01:20.814 --> 00:01:23.316 And in doing so, just like looking through a glass lens, 24 00:01:23.316 --> 00:01:25.985 it focuses the light onto our telescope. 25 00:01:26.352 --> 00:01:29.055 And in this case, we get just the right alignment 26 00:01:29.055 --> 00:01:33.226 with the lens and with the star in the background 27 00:01:33.526 --> 00:01:36.196 that we get really, really high magnifications. 28 00:01:36.229 --> 00:01:40.100 So in this case, it's magnified by a factor of thousands. 29 00:01:40.100 --> 00:01:43.770 Whereas typically, you know, if you have a lensed galaxy, 30 00:01:43.770 --> 00:01:47.841 it would be magnified by a factor of a few to perhaps ten. 31 00:01:48.675 --> 00:01:51.077 So in this case, we just got really lucky with the alignment. 32 00:01:51.077 --> 00:01:54.447 So we can really see very small details 33 00:01:54.681 --> 00:01:56.883 in this background object 34 00:02:00.353 --> 00:02:04.390 I think the most interesting thing is that it's looking back to a time 35 00:02:04.390 --> 00:02:08.094 when the universe was much different than what it is today. So 36 00:02:09.462 --> 00:02:10.530 what we've seen of 37 00:02:10.530 --> 00:02:14.667 galaxies at this early time, we can tell that they're structured very differently 38 00:02:14.667 --> 00:02:19.205 and that they look quite a bit different than galaxies that we see nearby. 39 00:02:19.239 --> 00:02:22.375 For example, the Milky Way and our nearest neighbor, Andromeda, 40 00:02:24.377 --> 00:02:26.880 So it stands to reason that stars 41 00:02:26.880 --> 00:02:29.983 at such a great distance will look a little bit different, too. 42 00:02:29.983 --> 00:02:34.454 And we just haven't had the opportunity to really study one in detail yet. 43 00:02:34.454 --> 00:02:38.591 So I think what I'm most interested in and what I'm most excited by is the fact 44 00:02:38.591 --> 00:02:42.896 that we now have an opportunity to really pinpoint one object 45 00:02:42.896 --> 00:02:45.698 and look at it in detail. 46 00:02:48.535 --> 00:02:51.271 Yeah, Hubble and Webb are very complementary. 47 00:02:51.838 --> 00:02:54.841 So Hubble obviously gets the shorter wavelengths of light, 48 00:02:54.841 --> 00:02:57.777 and Webb is able to target longer wavelengths. 49 00:02:58.444 --> 00:03:01.648 So when you combine those, you get a much broader understanding of 50 00:03:01.648 --> 00:03:02.882 whatever objects we're looking at. 51 00:03:03.816 --> 00:03:05.685 In my case as well, 52 00:03:05.685 --> 00:03:11.157 my group has both Hubble and Webb observations scheduled at the same time. 53 00:03:11.157 --> 00:03:13.726 So we're going to be able to get 54 00:03:13.860 --> 00:03:16.362 Hubble observations of this lensed star 55 00:03:16.362 --> 00:03:21.534 and Webb observations over a similar time period within the next year or so. 56 00:03:21.568 --> 00:03:25.471 So we'll will very much so be using the data from both of them together. 57 00:03:25.471 --> 00:03:28.708 And that's going to make our analysis of this 58 00:03:28.708 --> 00:03:30.510 much more powerful 59 00:03:33.980 --> 00:03:34.247 Yeah. 60 00:03:34.247 --> 00:03:37.650 You can learn more from the NASA website. 61 00:03:37.650 --> 00:03:40.887 So nasa.gov/Hubble, you can also follow 62 00:03:40.887 --> 00:03:43.122 on social media @NASAHubble. 63 00:03:43.923 --> 00:03:46.759 They also, especially on Instagram, have lots of pretty pictures 64 00:03:46.759 --> 00:03:47.760 from the Hubble telescope. 65 00:03:47.760 --> 00:03:49.963 That's one of my favorite accounts to follow 66 00:03:55.702 --> 00:03:58.438 So right now we can constrain roughly 67 00:03:58.438 --> 00:04:01.874 how bright it is and that can tell us about how massive it is. 68 00:04:02.675 --> 00:04:05.545 So we can estimate with the existing Hubble data 69 00:04:05.545 --> 00:04:08.548 that it's about 50 to 100 times the mass of the sun 70 00:04:10.550 --> 00:04:12.252 We also know that 71 00:04:12.252 --> 00:04:15.722 obviously it's at a time when the universe was less than a billion years old. 72 00:04:15.722 --> 00:04:19.592 So we can infer that it's probably going to look a little bit different 73 00:04:19.592 --> 00:04:23.630 than stars that we would see in the Milky Way, for example. 74 00:04:24.731 --> 00:04:28.034 And this is something that we're planning to follow up with the James 75 00:04:28.034 --> 00:04:29.969 Webb Space Telescope. 76 00:04:29.969 --> 00:04:32.105 So with that, we'll be able to say more. 77 00:04:32.105 --> 00:04:36.009 But right now we can tell that it's a very massive star and it's going to be 78 00:04:36.009 --> 00:04:38.511 a very interesting object to continue to study 79 00:04:43.383 --> 00:04:45.852 It is very likely no longer alive. 80 00:04:46.853 --> 00:04:48.321 It is so massive. 81 00:04:48.321 --> 00:04:51.524 Stars tend to live fast and die young, 82 00:04:52.191 --> 00:04:54.627 and this one being 50 to 100 times 83 00:04:54.627 --> 00:04:57.997 the mass of the sun, is absolutely living up to that. 84 00:04:57.997 --> 00:05:02.068 So it would have a lifetime of a few hundred million years. 85 00:05:02.702 --> 00:05:06.406 So it is most certainly no longer around today. 86 00:05:07.874 --> 00:05:08.675 So it's 87 00:05:08.675 --> 00:05:12.211 it's one of the few cases where the star that we're seeing is long dead. 88 00:05:12.211 --> 00:05:14.580 By the time we're able to see it 89 00:05:17.650 --> 00:05:21.054 So when we look back into the very distant 90 00:05:21.054 --> 00:05:24.290 universe, into a time when the universe was less than a billion years old, 91 00:05:25.124 --> 00:05:29.729 there's been much less time for stars to have lived and died and spread 92 00:05:29.729 --> 00:05:32.865 the heavier elements that they form into the rest of the universe. 93 00:05:34.534 --> 00:05:37.070 And so that means that this star is 94 00:05:37.070 --> 00:05:39.505 much more likely to be 95 00:05:41.007 --> 00:05:44.177 low metallicity, which means that there's not much else 96 00:05:44.177 --> 00:05:46.346 besides hydrogen and helium, 97 00:05:47.280 --> 00:05:50.516 and therefore, it's probably going to look quite a bit different than the stars 98 00:05:50.516 --> 00:05:51.451 that we see today. 99 00:05:51.451 --> 00:05:52.819 Like the sun. 100 00:05:52.819 --> 00:05:55.321 In part, it ends up being much more massive because of that. 101 00:05:56.422 --> 00:05:57.957 And it's since we know 102 00:05:57.957 --> 00:06:01.527 that the universe at this time is quite a bit different than the universe today. 103 00:06:01.994 --> 00:06:05.765 It's going to be very exciting to follow this up and get more information 104 00:06:05.765 --> 00:06:06.566 about it. 105 00:06:09.602 --> 00:06:10.970 Hubble's doing great. 106 00:06:10.970 --> 00:06:13.906 It's obviously still making a lot of great discoveries, 107 00:06:14.807 --> 00:06:19.879 and it's continuing to to pursue a wide array of science. 108 00:06:19.879 --> 00:06:24.183 And we expect that it will continue to do well 109 00:06:24.183 --> 00:06:27.387 and make awesome discoveries like this for years to come. 110 00:06:31.924 --> 00:06:32.959 I would love to say 111 00:06:32.959 --> 00:06:36.963 that there was a eureka moment, but it was really much more of a slow burn 112 00:06:38.297 --> 00:06:41.067 It turned into a lot of double checking whether or not 113 00:06:41.067 --> 00:06:44.504 we got our models right and trying to figure out if we did something wrong 114 00:06:45.204 --> 00:06:47.039 to get such a high magnification 115 00:06:48.374 --> 00:06:50.376 But once we did eventually 116 00:06:50.376 --> 00:06:53.146 get to a point that we believed that this was really a star 117 00:06:53.913 --> 00:06:56.416 at such a great distance, it was incredibly exciting. 118 00:06:57.450 --> 00:07:00.887 And it was really fun to get to work on something like this 119 00:07:00.887 --> 00:07:04.290 and to be part of this discovery 120 00:07:07.160 --> 00:07:07.427 Yeah. 121 00:07:07.427 --> 00:07:11.431 So the star is nicknamed Earendel, which is an old English word 122 00:07:11.431 --> 00:07:14.534 that means the Morning Star 123 00:07:14.767 --> 00:07:17.670 So the time period that we found the object 124 00:07:17.670 --> 00:07:22.074 in within the first billion years is referred to generally as Cosmic Dawn. 125 00:07:23.042 --> 00:07:25.378 So we found that a sort of 126 00:07:25.378 --> 00:07:27.680 Morning Star kind of name fit very well. 127 00:07:29.549 --> 00:07:32.919 It's also for the Lord of the Rings nerds out there. 128 00:07:32.919 --> 00:07:36.088 It's the same old English word that Tolkien 129 00:07:36.088 --> 00:07:39.425 used for inspiration for a character from the Silmarillion 130 00:07:40.426 --> 00:07:42.295 who also ends up becoming a star. 131 00:07:42.295 --> 00:07:45.832 So it's a nice parallel there 132 00:07:45.932 --> 00:07:49.035 and we just we figured that The Morning Star 133 00:07:49.035 --> 00:07:51.871 seemed to fit for such an early object 134 00:07:56.843 --> 00:08:00.079 So I was kind of given a typical grad student 135 00:08:00.079 --> 00:08:02.849 project of Here's some data, see what you can find 136 00:08:03.816 --> 00:08:08.087 So we knew that the galaxy that this star is sitting 137 00:08:08.087 --> 00:08:11.491 in was very highly magnified by the foreground 138 00:08:12.358 --> 00:08:14.727 galaxy cluster, which is acts as the lens. 139 00:08:15.528 --> 00:08:18.030 So we end up seeing the lensed galaxy 140 00:08:18.030 --> 00:08:20.132 as this long banana shaped arc. 141 00:08:21.901 --> 00:08:24.270 And we can tell from the just the first image 142 00:08:24.270 --> 00:08:28.040 that it was longer than any lensed arc 143 00:08:28.040 --> 00:08:30.276 at this distance that we had seen before. 144 00:08:31.110 --> 00:08:33.212 So I was given the task of 145 00:08:33.412 --> 00:08:36.315 figuring out what the galaxy looked like. 146 00:08:36.315 --> 00:08:37.717 And in the process of that 147 00:08:37.717 --> 00:08:41.754 and the process of figuring out how highly magnified it was, I 148 00:08:42.788 --> 00:08:45.458 sort of stumbled on to the fact that this one part of it 149 00:08:45.458 --> 00:08:48.327 seemed like it was at a very, very high magnification. 150 00:08:48.794 --> 00:08:51.731 And the more that we looked into it, the more it became clear 151 00:08:51.731 --> 00:08:54.534 that it was too small to be anything other than a star. 152 00:08:55.268 --> 00:08:59.639 So that was how we sort of came to the conclusion that this is a lensed star.