WEBVTT FILE 1 00:00:00.200 --> 00:00:04.938 [Music] 2 00:00:04.938 --> 00:00:07.841 There are many important reasons for studying asteroids 3 00:00:07.841 --> 00:00:10.744 like the target of OSIRIS-REx, asteroid Bennu. 4 00:00:10.744 --> 00:00:13.814 First and foremost, for me especially, they're geologic 5 00:00:13.814 --> 00:00:16.116 remnants from the dawn of our solar system. 6 00:00:16.116 --> 00:00:19.052 They're literally the first material that formed around our 7 00:00:19.052 --> 00:00:22.890 star, and they represent the building blocks of planets, and 8 00:00:22.890 --> 00:00:26.326 we hope, in the case of Bennu of life, and the reason that Earth 9 00:00:26.326 --> 00:00:28.996 may be a habitable planet in the form of delivering water and 10 00:00:28.996 --> 00:00:31.198 other important volatile material. 11 00:00:31.198 --> 00:00:33.934 When we look at asteroids which are these primitive objects, 12 00:00:33.934 --> 00:00:37.704 these little leftover pieces from solar system formation, and 13 00:00:37.704 --> 00:00:40.707 we find they may have organics, then that tells us perhaps the 14 00:00:40.707 --> 00:00:43.110 conditions for life could have erupted anywhere in the solar 15 00:00:43.110 --> 00:00:45.312 system, and Earth was just right. 16 00:00:45.312 --> 00:00:48.682 When we study meteorites, we think they represent these 17 00:00:48.682 --> 00:00:51.385 asteroids and their different histories, but they've all 18 00:00:51.385 --> 00:00:55.088 interacted with the Earth's atmosphere, its biosphere, its 19 00:00:55.088 --> 00:00:57.758 hydrosphere, and so we don't know what effect just 20 00:00:57.758 --> 00:01:01.061 interacting with the Earth has had on these meteorites. 21 00:01:01.061 --> 00:01:05.032 We really want to get samples that are pristine, and so we can 22 00:01:05.032 --> 00:01:07.601 do all of those things through this mission. 23 00:01:07.601 --> 00:01:11.805 OSIRIS-REx is a mission in the NASA New Frontiers Program. 24 00:01:11.805 --> 00:01:15.342 Our objective is to travel out to a near-Earth asteroid named 25 00:01:15.342 --> 00:01:19.346 Bennu, survey that object in great detail to understand its 26 00:01:19.346 --> 00:01:23.650 geology, its mineralogy and composition, ultimately select a 27 00:01:23.650 --> 00:01:26.286 single location on the asteroid's surface to acquire a 28 00:01:26.286 --> 00:01:29.423 sample, and return that material back to the Earth for scientific 29 00:01:29.423 --> 00:01:30.857 analysis. 30 00:01:30.857 --> 00:01:33.961 Asteroid Bennu is a fragment of the early solar system, an 31 00:01:33.961 --> 00:01:37.998 un-melted, unaltered piece of the origin of the solar system. 32 00:01:37.998 --> 00:01:41.268 It preserves the ingredients, the raw materials that went into 33 00:01:41.268 --> 00:01:44.237 the formation of planets, the formation of life. 34 00:01:44.237 --> 00:01:47.441 By bringing a sample back to the Earth, such as OSIRIS-REx will 35 00:01:47.441 --> 00:01:51.545 do with samples of Bennu in 2023. we'll be able to look at 36 00:01:51.545 --> 00:01:54.948 the samples in laboratories around the world, to understand 37 00:01:54.948 --> 00:02:00.087 in great detail the nature of the sample and its place in the 38 00:02:00.087 --> 00:02:01.922 origin of the solar system. 39 00:02:01.922 --> 00:02:04.891 The OSIRIS-REx spacecraft launched in 2016, and it's 40 00:02:04.891 --> 00:02:08.762 actually taken us two years to get to the asteroid Bennu, and 41 00:02:08.762 --> 00:02:10.497 in that time we had an Earth flyby. 42 00:02:10.497 --> 00:02:14.334 So, we used an Earth flyby in 2017 to change the plane of our 43 00:02:14.334 --> 00:02:17.604 orbit to match Bennu's orbit plane, and it's also provided a 44 00:02:17.604 --> 00:02:21.208 great opportunity from a flight dynamics perspective to really 45 00:02:21.208 --> 00:02:24.411 calibrate our models and learn how to fly the spacecraft which 46 00:02:24.411 --> 00:02:26.980 will help us in the really challenging part of the mission, 47 00:02:26.980 --> 00:02:29.516 which is orbiting in the low-gravity environment of the 48 00:02:29.516 --> 00:02:30.751 asteroid. 49 00:02:30.751 --> 00:02:32.919 Over the past few months, the flight dynamics team has been 50 00:02:32.919 --> 00:02:35.689 getting images of the asteroid Bennu, and it started out as 51 00:02:35.689 --> 00:02:38.892 just a very small point source in the camera, and it's been 52 00:02:38.892 --> 00:02:41.561 getting bigger and bigger and bigger in the field of view. 53 00:02:41.561 --> 00:02:45.232 And that's allowed us to perform optical navigation, to refine 54 00:02:45.232 --> 00:02:49.236 our prediction of the asteroid's orbit, and allow us to more 55 00:02:49.236 --> 00:02:53.040 precisely navigate and target our approach to the asteroid. 56 00:02:53.040 --> 00:02:56.043 As OSIRIS-REx approaches the asteroid, we've done a series of 57 00:02:56.043 --> 00:02:58.412 braking maneuvers called Asteroid Approach Maneuvers to 58 00:02:58.412 --> 00:03:01.615 slow down the spacecraft, so that we can get into orbit 59 00:03:01.615 --> 00:03:03.550 around the asteroid later this year. 60 00:03:03.550 --> 00:03:06.887 We're also taking lots of images of Bennu to understand its 61 00:03:06.887 --> 00:03:09.856 rotation, look for natural satellites, and potential dust 62 00:03:09.856 --> 00:03:11.058 plumes. 63 00:03:11.058 --> 00:03:14.127 This is an extremely exciting time on OSIRIS-REx as we're just 64 00:03:14.127 --> 00:03:16.029 poised at arrival at Bennu. 65 00:03:16.029 --> 00:03:18.799 And one of the most exciting things to us, and relieving too 66 00:03:18.799 --> 00:03:22.269 to the engineers, is how closely the asteroid has resembled what 67 00:03:22.269 --> 00:03:23.270 we had predicted. 68 00:03:23.270 --> 00:03:26.273 Early on our science team, prior to launch, had come up with of a 69 00:03:26.273 --> 00:03:29.142 model of what they thought the asteroid would look like, based 70 00:03:29.142 --> 00:03:32.712 purely on ground-based radar observations from Arecibo, and 71 00:03:32.712 --> 00:03:36.349 from that they created a reference asteroid that we used 72 00:03:36.349 --> 00:03:38.752 as the requirements to design the mission against. 73 00:03:38.752 --> 00:03:41.054 But no one could be sure that the asteroid would really look 74 00:03:41.054 --> 00:03:43.256 like the scientists had predicted, so it's been a 75 00:03:43.256 --> 00:03:47.060 tremendous relief to us to find that the actual Bennu is very 76 00:03:47.060 --> 00:03:49.563 similar to what the scientists had predicted. 77 00:03:49.563 --> 00:03:51.264 So, the science team really nailed it. 78 00:03:51.264 --> 00:03:54.367 Well right now as we're approaching asteroid Bennu, 79 00:03:54.367 --> 00:03:57.771 we're looking for debris or other objects that are orbiting 80 00:03:57.771 --> 00:04:00.373 the asteroid just in case we need to avoid those. 81 00:04:00.373 --> 00:04:03.176 And then once we arrive on December 3 we'll perform 82 00:04:03.176 --> 00:04:06.046 Preliminary Survey, and in Preliminary Survey we fly over 83 00:04:06.046 --> 00:04:08.982 the north pole, south pole, and the middle of the asteroid. 84 00:04:08.982 --> 00:04:11.985 This helps us to map the gravity of the asteroid and understand 85 00:04:11.985 --> 00:04:14.421 how to operate near such a small body. 86 00:04:14.421 --> 00:04:16.656 Additionally, this will be the first time that we get close-up 87 00:04:16.656 --> 00:04:19.292 pictures of the surface, and we'll know how smooth or rocky 88 00:04:19.292 --> 00:04:21.161 the surface that we're going to study is. 89 00:04:21.161 --> 00:04:25.098 As we get closer to asteroid Bennu, we'll begin to map its 90 00:04:25.098 --> 00:04:27.968 surface in higher detail. 91 00:04:27.968 --> 00:04:31.872 What we'll be able to do is first identify the distribution 92 00:04:31.872 --> 00:04:36.176 of rocks and particles that might pose a hazard to the 93 00:04:36.176 --> 00:04:39.479 sampling mechanism on the spacecraft, and we'll also get a 94 00:04:39.479 --> 00:04:42.849 better sense of what the shape of Bennu is like at smaller 95 00:04:42.849 --> 00:04:43.517 scales. 96 00:04:43.517 --> 00:04:46.820 Looking at Bennu in more and more detail is going to help us 97 00:04:46.820 --> 00:04:50.524 identify all the areas that we shouldn't go to grab a sample 98 00:04:50.524 --> 00:04:51.191 from. 99 00:04:51.191 --> 00:04:54.261 Throughout 2019 we'll be doing global characterization of the 100 00:04:54.261 --> 00:04:57.797 asteroid, basically making maps of the entire surface. 101 00:04:57.797 --> 00:05:00.100 We're interested in its topography. 102 00:05:00.100 --> 00:05:01.034 Are there craters? 103 00:05:01.034 --> 00:05:03.703 Where are the boulders, the valleys, the mountains of the 104 00:05:03.703 --> 00:05:04.371 asteroid? 105 00:05:04.371 --> 00:05:07.240 And then we want to understand the distribution of geologic 106 00:05:07.240 --> 00:05:10.177 materials: are we finding different patches of minerals in 107 00:05:10.177 --> 00:05:13.680 one location versus another, and why are certain areas that have 108 00:05:13.680 --> 00:05:15.682 a composition and others maybe different? 109 00:05:15.682 --> 00:05:19.085 We're going to be looking most importantly for areas where we 110 00:05:19.085 --> 00:05:21.021 can collect a sample. 111 00:05:21.021 --> 00:05:24.424 OSIRIS-REx will collect a sample from Bennu using our TAGSAM, 112 00:05:24.424 --> 00:05:27.594 which is the Touch And Go Sample Acquisition Mechanism. 113 00:05:27.594 --> 00:05:30.697 What that is, is an arm connected to this sampler head 114 00:05:30.697 --> 00:05:31.464 that you see here. 115 00:05:31.464 --> 00:05:34.968 This is similar in size to an air filter from a car. 116 00:05:34.968 --> 00:05:38.238 How this mechanism works is there's compressed gas that is 117 00:05:38.238 --> 00:05:41.174 released that will stir up the regolith from Bennu, store it 118 00:05:41.174 --> 00:05:44.611 into this canister, which we will then put inside of our 119 00:05:44.611 --> 00:05:47.080 sample release capsule and bring back to Earth. 120 00:05:47.080 --> 00:05:50.617 We will collect the sample of Bennu in 2020 and return it to 121 00:05:50.617 --> 00:05:51.751 Earth in 2023. 122 00:05:51.751 --> 00:05:55.889 Once we're in the vicinity of our home world, about 123 00:05:55.889 --> 00:05:59.226 four-and-a-half hours before impacting the top of the 124 00:05:59.226 --> 00:06:02.162 atmosphere, the spacecraft spins up and releases that sample 125 00:06:02.162 --> 00:06:02.963 return capsule. 126 00:06:02.963 --> 00:06:06.867 The spacecraft fires its engines to perform a deflection burn, 127 00:06:06.867 --> 00:06:09.936 going off into orbit around the sun, and the return capsule 128 00:06:09.936 --> 00:06:13.173 enters the Earth's atmosphere, targeting a landing in the Utah 129 00:06:13.173 --> 00:06:14.074 desert. 130 00:06:14.074 --> 00:06:17.344 I'll be there on site when we open that capsule up and we see 131 00:06:17.344 --> 00:06:21.014 those samples for the first time, and science begins at that 132 00:06:21.014 --> 00:06:23.984 point on the next phase of the mission, the sample analysis 133 00:06:23.984 --> 00:06:24.985 period. 134 00:06:24.985 --> 00:06:27.520 [Music] 135 00:06:27.520 --> 00:06:39.266 [Satellite beeping]