WEBVTT FILE 1 00:00:00.200 --> 00:00:01.434 My name is Danny Glavin. 2 00:00:01.434 --> 00:00:04.738 I'm an astrobiologist at NASA's Goddard Space Flight Center. 3 00:00:05.105 --> 00:00:08.675 And I'm leading the sample organics analysis team for the OSIRIS-REx mission. 4 00:00:09.342 --> 00:00:13.580 So, OSIRIS-REx is NASA's first asteroid sample return mission. 5 00:00:13.580 --> 00:00:19.519 It launched in 2016, rendezvoused with asteroid Bennu in 2018, 6 00:00:19.819 --> 00:00:23.790 collected a sample from the surface of the asteroid in 2020, 7 00:00:24.024 --> 00:00:28.094 and then brought it back to Earth, where it landed in Utah in 2023. 8 00:00:28.361 --> 00:00:32.332 And now this sample is available for scientists to study around the world 9 00:00:32.632 --> 00:00:35.835 to look for chemicals, including the building blocks of life, 10 00:00:35.835 --> 00:00:38.838 which is what our team is interested in. 11 00:00:38.872 --> 00:00:42.375 So our team, which included an international group of scientists 12 00:00:42.375 --> 00:00:45.945 led by our colleagues in Japan at Tohoku University, 13 00:00:46.446 --> 00:00:51.518 discovered evidence for bio-essential sugars, sugar molecules 14 00:00:51.518 --> 00:00:55.155 essential for life in the samples returned from asteroid Bennu. 15 00:00:55.422 --> 00:00:59.325 We actually found six different sugars, including two - 16 00:00:59.325 --> 00:01:03.029 ribose and glucose - that are fundamental for life as we know it. 17 00:01:03.263 --> 00:01:07.200 The reason that this discovery of ribose and glucose is so exciting 18 00:01:07.200 --> 00:01:11.337 is ribose is actually a fundamental component of nucleic acids, 19 00:01:11.371 --> 00:01:15.075 it forms the sugar phosphate backbone of RNA. 20 00:01:15.275 --> 00:01:19.813 Glucose is is an important source of energy for all living organisms, 21 00:01:20.880 --> 00:01:24.217 and this is the first discovery of glucose in any astromaterial. 22 00:01:24.217 --> 00:01:27.320 So this is this is truly exciting, a very big surprise. 23 00:01:27.320 --> 00:01:30.323 We weren't expecting to find this in the samples. 24 00:01:30.890 --> 00:01:33.927 So in order to detect these sugars essential for life, 25 00:01:33.927 --> 00:01:37.597 we actually had to take some of the Bennu chips and crush them up. 26 00:01:37.797 --> 00:01:40.500 We made a powder. Kind of like making flour. 27 00:01:40.500 --> 00:01:45.205 We used about 600 milligrams, so a fair amount of sample, 28 00:01:45.205 --> 00:01:49.642 and then we basically extracted it in water at cool temperatures, 29 00:01:49.642 --> 00:01:52.645 kind of like making a cold, cold brew, a cold tea, 30 00:01:52.779 --> 00:01:55.782 and then extracted the sugars into that water. 31 00:01:56.015 --> 00:01:59.719 Then we analyzed the water by a technique called gas chromatography 32 00:01:59.719 --> 00:02:00.820 mass spectrometry. 33 00:02:00.820 --> 00:02:03.823 Kind of a mouthful, but basically it allows you to separate 34 00:02:03.823 --> 00:02:08.328 the individual sugars and measure them and identify them by their masses. 35 00:02:09.462 --> 00:02:12.332 This discovery of these bio-essential sugars 36 00:02:12.332 --> 00:02:16.202 was led by our colleagues in Japan on the OSIRIS-REx mission 37 00:02:16.503 --> 00:02:20.373 from Tohoku University, Hokkaido University, and JAMSTEC. 38 00:02:21.307 --> 00:02:26.045 We helped them at NASA crush the samples to provide them with the powder, 39 00:02:26.446 --> 00:02:29.482 where they did the extractions in Japan and were able 40 00:02:29.482 --> 00:02:32.952 to detect these sugars including ribose and glucose, 41 00:02:33.286 --> 00:02:37.023 using these gas chromatography mass spectrometry techniques. 42 00:02:37.490 --> 00:02:38.658 So this is really exciting. 43 00:02:38.658 --> 00:02:43.096 This is truly a joint effort to make these these really important discoveries, 44 00:02:43.429 --> 00:02:44.597 and I'm proud to say 45 00:02:44.597 --> 00:02:47.767 that this is really an international team that made this happen. 46 00:02:48.635 --> 00:02:48.835 Yeah. 47 00:02:48.835 --> 00:02:53.173 So this discovery really builds on some of the earlier findings of the mission. 48 00:02:53.873 --> 00:02:57.610 When we first started the sample analysis, we discovered amino acids. 49 00:02:57.610 --> 00:03:01.047 In fact, 14 of the 20 protein amino acids found in life. 50 00:03:01.548 --> 00:03:04.284 And we also found the nucleobases. 51 00:03:04.284 --> 00:03:08.354 These are the components of the genetic code in DNA and RNA. 52 00:03:08.354 --> 00:03:11.591 All five, in fact, and phosphates. 53 00:03:11.624 --> 00:03:16.196 So we had all the components that we needed to make proteins and enzymes 54 00:03:16.596 --> 00:03:20.266 and almost all of the components we needed to make RNA. 55 00:03:20.300 --> 00:03:25.071 We have the phosphate and the nucleobases, but not the sugar. 56 00:03:25.405 --> 00:03:28.341 And so this discovery of ribose was actually really critical. 57 00:03:28.341 --> 00:03:31.778 It filled in that missing component of this nucleic acid 58 00:03:31.778 --> 00:03:35.381 that some believe was really needed for the origin of life on Earth. 59 00:03:36.082 --> 00:03:36.249 Yeah. 60 00:03:36.249 --> 00:03:39.752 So what we're learning now with the discovery of all the three main 61 00:03:39.752 --> 00:03:43.323 components, the building blocks of life and the samples from Bennu, 62 00:03:43.590 --> 00:03:46.893 is that these actually formed very early on in the outer 63 00:03:46.893 --> 00:03:50.496 part of the solar system, 4.5 billion years ago. 64 00:03:50.897 --> 00:03:54.701 You had chemical reactions inside the asteroid Bennu parent body. 65 00:03:54.701 --> 00:04:00.139 This icy body with melting and fluid, salty brines that actually formed 66 00:04:00.373 --> 00:04:03.376 the sugars and some of these other building blocks of life. 67 00:04:03.776 --> 00:04:07.013 And then the parent body was flung into the inner 68 00:04:07.013 --> 00:04:10.350 solar system, into the asteroid belt, where it was eventually disrupted 69 00:04:10.350 --> 00:04:15.088 and reaccreted to have what we now have, asteroid Bennu, a rubble pile. 70 00:04:15.388 --> 00:04:18.891 What this means is that these building blocks of life were distributed 71 00:04:18.891 --> 00:04:21.995 from the outer solar system all the way into the inner solar system. 72 00:04:22.028 --> 00:04:26.499 They were everywhere, ubiquitous, which really makes me more optimistic 73 00:04:26.499 --> 00:04:30.470 that not only could these building blocks have enabled life on Earth, 74 00:04:30.470 --> 00:04:34.507 but potentially elsewhere, Mars, Europa, the outer solar system. 75 00:04:34.807 --> 00:04:38.478 I'm becoming much more optimistic that we may be able to find life 76 00:04:38.478 --> 00:04:41.481 beyond Earth, even in our own solar system. 77 00:04:41.547 --> 00:04:44.250 So I just want to make it clear that even though we found 78 00:04:44.250 --> 00:04:48.321 all of the chemical building blocks to make proteins and nucleic acids, 79 00:04:48.321 --> 00:04:51.591 we haven't found evidence for life itself in Bennu. 80 00:04:52.225 --> 00:04:55.228 We don't see nucleic acids or large polymers. 81 00:04:55.461 --> 00:04:58.097 And this actually opens up a whole new area of research. 82 00:04:58.097 --> 00:04:59.499 And the question is why? 83 00:04:59.499 --> 00:05:03.369 Why didn't we have more chemistry leading to the origin of life 84 00:05:03.536 --> 00:05:06.572 happening inside this giant parent body? 85 00:05:07.073 --> 00:05:09.742 Did we not have enough time to form them? 86 00:05:09.742 --> 00:05:12.078 Or were the temperatures too cold? 87 00:05:12.078 --> 00:05:14.247 What is the answer to that question? 88 00:05:14.247 --> 00:05:15.348 I think this is going to open up 89 00:05:15.348 --> 00:05:18.484 a lot of new areas of research for folks to try to figure out, 90 00:05:18.718 --> 00:05:20.720 why didn't these building blocks advance 91 00:05:20.720 --> 00:05:24.891 to something more complex inside this giant asteroid parent body? 92 00:05:25.925 --> 00:05:26.893 So life, of 93 00:05:26.893 --> 00:05:30.663 course, requires the right environment, liquid water, energy sources, 94 00:05:30.663 --> 00:05:34.334 but it also requires these fundamental chemical building blocks. 95 00:05:34.334 --> 00:05:37.337 And we've already talked about the amino acids needed for proteins, 96 00:05:37.704 --> 00:05:41.674 the nucleobases, the genetic components of DNA and RNA, 97 00:05:41.774 --> 00:05:46.179 but also sugars, which can act as an energy source for life. 98 00:05:46.546 --> 00:05:49.115 We found all three of those in Bennu, 99 00:05:49.115 --> 00:05:52.785 and we've been looking for them in other asteroids and meteorites as well. 100 00:05:52.819 --> 00:05:54.954 So asteroid Ryugu, 101 00:05:54.954 --> 00:05:59.158 we have samples returned from that asteroid from the Japanese Hayabusa2 102 00:05:59.158 --> 00:06:03.763 mission, and we're looking for sugars in those samples right now. 103 00:06:03.963 --> 00:06:08.067 One of the challenges is that you need a lot more sample to analyze sugars. 104 00:06:08.267 --> 00:06:08.835 They're present 105 00:06:08.835 --> 00:06:12.505 at much lower concentrations than the amino acids and the nucleobases. 106 00:06:12.505 --> 00:06:16.909 And so with the Bennu samples, we've had the luxury of having more sample 107 00:06:16.909 --> 00:06:19.979 to work with to actually target these compounds. 108 00:06:20.313 --> 00:06:22.982 But right now, scientists are actively looking 109 00:06:22.982 --> 00:06:25.985 for these sugars in the Ryugu samples as well. 110 00:06:26.119 --> 00:06:29.122 And I wouldn't be surprised if we found them there as well. 111 00:06:30.022 --> 00:06:32.291 It's absolutely crucial that we return 112 00:06:32.291 --> 00:06:36.095 and bring back samples of pristine asteroid materials. 113 00:06:36.229 --> 00:06:39.766 We've got plenty of meteorites that we know are fragments of asteroids 114 00:06:39.999 --> 00:06:43.035 littered all over the Earth, but they get contaminated. 115 00:06:43.236 --> 00:06:46.406 The first thing that happens is a meteorite will come through the atmosphere 116 00:06:46.406 --> 00:06:49.509 and it'll be heated by atmospheric entry heating, potentially 117 00:06:49.509 --> 00:06:52.812 thermally destroying some of these fragile organic compounds. 118 00:06:53.079 --> 00:06:56.516 And then the meteorite hits the Earth, and immediately it's contaminated by 119 00:06:56.783 --> 00:06:57.650 by the soil. 120 00:06:57.650 --> 00:07:02.221 Bacteria in the soil, organics, water, which can make it really hard to be able 121 00:07:02.221 --> 00:07:04.757 to discriminate between an organic compound 122 00:07:04.757 --> 00:07:06.659 that's a terrestrial contaminant versus 123 00:07:06.659 --> 00:07:09.662 an organic molecule that was actually formed in space. 124 00:07:09.762 --> 00:07:14.300 So having these pristine materials from asteroid Bennu and asteroid Ryugu 125 00:07:14.300 --> 00:07:17.303 is really a precious opportunity. 126 00:07:17.336 --> 00:07:20.440 We have these samples that were protected from the atmospheric entry 127 00:07:20.440 --> 00:07:22.141 heating by the shield. 128 00:07:22.141 --> 00:07:25.211 They were contained in containers to protect them 129 00:07:25.311 --> 00:07:26.646 from the terrestrial environment. 130 00:07:26.646 --> 00:07:30.049 And so we know that these samples are clean from contamination. 131 00:07:30.283 --> 00:07:33.052 Bottom line is, with these pristine asteroid materials, 132 00:07:33.052 --> 00:07:36.823 we can trust the results when we detect these sugars and other molecules. 133 00:07:37.023 --> 00:07:40.026 We know that they were formed in space and came from these samples 134 00:07:40.026 --> 00:07:43.229 and weren't a product of terrestrial contaminants from the Earth. 135 00:07:44.063 --> 00:07:47.867 So one of the biggest scientific mysteries is how we all came to be. 136 00:07:47.900 --> 00:07:50.903 How did life start on the Earth? 137 00:07:50.970 --> 00:07:54.707 In order to answer that question, we go to these asteroids like asteroid 138 00:07:54.707 --> 00:07:59.078 Bennu and bring back samples to look for the chemical building blocks of life, 139 00:07:59.278 --> 00:08:03.182 to try to get clues into how life may have started on the Earth. 140 00:08:03.716 --> 00:08:06.886 Of course, with this new research, we've now found sugars, 141 00:08:06.886 --> 00:08:09.922 the missing component of the three that we need for life. 142 00:08:09.922 --> 00:08:12.758 So we have the amino acids, the nucleobases, 143 00:08:12.758 --> 00:08:15.761 and the sugars needed for proteins and nucleic acids. 144 00:08:16.062 --> 00:08:19.765 But I think what's really key here is that we're showing that these compounds 145 00:08:19.765 --> 00:08:24.003 were widespread throughout the early solar system, formed in the outer solar system 146 00:08:24.003 --> 00:08:28.808 and then delivered to the inner planets, such as Earth and Mars. 147 00:08:29.141 --> 00:08:31.377 And so I think we're we're really beginning to understand 148 00:08:31.377 --> 00:08:34.547 that these chemical building blocks were not only ubiquitous, 149 00:08:34.547 --> 00:08:38.417 but were also delivered to environments on the early Earth and potentially 150 00:08:38.417 --> 00:08:41.554 other planets that would have enabled the origin of life. 151 00:08:41.554 --> 00:08:43.322 And for me, this is really exciting. 152 00:08:43.322 --> 00:08:45.224 It really makes me more optimistic 153 00:08:45.224 --> 00:08:48.160 that if life started elsewhere in the solar system, 154 00:08:48.160 --> 00:08:51.564 the building blocks were available to do it, and I think we're going to find it. 155 00:08:52.532 --> 00:08:53.132 So we found 156 00:08:53.132 --> 00:08:57.436 ribose in the Bennu samples, which is a really important finding 157 00:08:57.436 --> 00:09:02.909 because ribose is an important component of RNA as the sugar phosphate backbone. 158 00:09:03.342 --> 00:09:05.912 RNA, some have argued, was actually 159 00:09:05.912 --> 00:09:09.148 the first genetic material that started at the origin of life. 160 00:09:09.148 --> 00:09:12.151 It's called the RNA world hypothesis. 161 00:09:12.285 --> 00:09:16.956 And that DNA and the protein world followed subsequently. 162 00:09:17.723 --> 00:09:20.259 One of the interesting findings, actually, with the Bennu samples 163 00:09:20.259 --> 00:09:22.695 isn't what we found, but what we didn't find. 164 00:09:22.695 --> 00:09:26.899 We didn't find deoxyribose, which is 165 00:09:26.899 --> 00:09:30.403 the equivalent sugar in DNA that forms the backbone of DNA. 166 00:09:30.670 --> 00:09:35.975 Deoxyribose, we didn't see it above our detection limits, but ribose was present. 167 00:09:35.975 --> 00:09:40.346 So I think this supports this idea that maybe RNA did come first 168 00:09:40.346 --> 00:09:45.952 because there was more ribose available as its building block very early on, 169 00:09:45.952 --> 00:09:51.123 and perhaps DNA and deoxyribose did come later on in biological evolution. 170 00:09:51.757 --> 00:09:56.596 Some people consider the origin of life just a simple nucleic acid like RNA 171 00:09:56.929 --> 00:10:01.200 that could make copies of itself and transfer information that way. 172 00:10:01.434 --> 00:10:05.871 Didn't even require DNA or proteins or even a cell membrane. 173 00:10:05.871 --> 00:10:08.908 So this discovery of ribose, in fact, is really important 174 00:10:09.275 --> 00:10:12.311 and adds more credibility to that hypothesis that maybe 175 00:10:12.311 --> 00:10:15.581 the origin of life was just a single strand of RNA. 176 00:10:16.449 --> 00:10:19.318 One of the goals of the OREX mission was actually to study 177 00:10:19.318 --> 00:10:23.489 asteroid Bennu, which has been classified as a potentially hazardous asteroid 178 00:10:23.756 --> 00:10:28.227 because its orbit crosses Earth's orbit every now and again. 179 00:10:28.527 --> 00:10:32.531 And so the mission actually determined that the threat of impact 180 00:10:32.598 --> 00:10:36.369 of Bennu on Earth is very low: 181 00:10:36.369 --> 00:10:39.505 0.037%. 1 in 2700 chance 182 00:10:39.505 --> 00:10:42.541 of hitting the Earth in September of 2182. 183 00:10:42.541 --> 00:10:44.910 So, well in the future. 184 00:10:44.910 --> 00:10:46.679 In fact, there's zero probability 185 00:10:46.679 --> 00:10:49.715 that Bennu will hit the Earth in the next 150 years. 186 00:10:49.982 --> 00:10:53.519 But the other aspect of this mission that was important, it was actually able 187 00:10:53.519 --> 00:10:56.789 to touch the asteroid to see what it feels like. 188 00:10:57.056 --> 00:11:00.593 During the sampling we actually sunk in to asteroid Bennu, 189 00:11:00.626 --> 00:11:02.628 which was quite an unexpected. 190 00:11:02.628 --> 00:11:05.798 We thought we were going to kind of springboard off the asteroid. 191 00:11:05.798 --> 00:11:07.633 So we learned just by touching it 192 00:11:07.633 --> 00:11:10.870 kind of how it was made up, but we also returned the samples. 193 00:11:10.870 --> 00:11:12.705 We have the samples in our lab 194 00:11:12.705 --> 00:11:15.708 to understand their physical and chemical properties, 195 00:11:15.841 --> 00:11:20.780 and all of this information is going to be really important for designing a mission 196 00:11:20.780 --> 00:11:24.050 if we ever have to deflect an asteroid like Bennu in the future so that, 197 00:11:24.517 --> 00:11:26.185 you know, [it will] avoid colliding with the Earth.