1 00:00:00,030 --> 00:00:04,010 [slate] 2 00:00:04,030 --> 00:00:08,020 [slate] 3 00:00:08,040 --> 00:00:12,080 4 00:00:12,100 --> 00:00:16,080 So exoplanets are planets 5 00:00:16,100 --> 00:00:20,090 outside of our solar system, they're orbiting other stars 6 00:00:20,110 --> 00:00:24,290 and that makes them very far away. So it's very difficult 7 00:00:24,310 --> 00:00:28,290 to observe details about exoplanets. We have to use special 8 00:00:28,310 --> 00:00:32,300 techniques to do that. The way we have used the Hubble Space 9 00:00:32,320 --> 00:00:36,320 Telescope to understand atmospheres of exoplanets is 10 00:00:36,340 --> 00:00:40,350 to look at those planets as they orbit around their parent star 11 00:00:40,370 --> 00:00:44,370 and when they sort of transit in front of that parent star, some of that starlight comes 12 00:00:44,390 --> 00:00:48,550 through the atmosphere surrounding the planet. And the atmosphere 13 00:00:48,570 --> 00:00:52,580 may absorb some of that light. And we can tell from the spectroscopic 14 00:00:52,600 --> 00:00:56,620 patterns of that light absorption what's in the atmosphere. 15 00:00:56,640 --> 00:01:00,640 In this case scientists have used the Hubble in this way to look at the spectroscopic 16 00:01:00,660 --> 00:01:04,660 signature of a planet transiting in front of its parent 17 00:01:04,680 --> 00:01:08,680 star to detect the signature of water vapor 18 00:01:08,700 --> 00:01:12,690 in the atmosphere of that exoplanet. And this is exciting news because it's not 19 00:01:12,710 --> 00:01:16,690 the first time we've seen water vapor in an exoplanet. There's some very 20 00:01:16,710 --> 00:01:20,870 large planets, big Jupiter-sized things that we've seen water vapor in. 21 00:01:20,890 --> 00:01:24,890 But this time, this planet is what we call a super-Earth. It's about eight times 22 00:01:24,910 --> 00:01:28,910 the mass of the Earth, which sounds big, but that's still a kind 23 00:01:28,930 --> 00:01:32,960 of planet that might be somewhat similar to Earth. And it also 24 00:01:32,980 --> 00:01:36,990 distance from its star where we might have moderate temperatures that would allow 25 00:01:37,010 --> 00:01:41,170 for liquid water and potentially habitability of that planet. 26 00:01:41,190 --> 00:01:45,190 So it's the next step in our investigations of exoplanets 27 00:01:45,210 --> 00:01:49,210 to see if any of them are like the planets in our own solar system. 28 00:01:49,230 --> 00:01:53,220 [slate] 29 00:01:53,240 --> 00:01:57,240 [slate] 30 00:01:57,260 --> 00:02:01,290 We don't know whether or not there could be life on 31 00:02:01,310 --> 00:02:05,290 this exoplanet. This is a next step in kind of studying what 32 00:02:05,310 --> 00:02:09,430 exoplanets are like. We're trying to understand if any of them could be 33 00:02:09,450 --> 00:02:13,460 very similar to Earth and could be habitable for life. 34 00:02:13,480 --> 00:02:17,620 One piece of that equation is to find planets like this one 35 00:02:17,640 --> 00:02:21,820 where the temperature might be moderate enough to allow water 36 00:02:21,840 --> 00:02:25,830 to be in liquid form - not so cold that it's frozen as ice 37 00:02:25,850 --> 00:02:29,830 or so hot that it boils away. This planet seems to be at that 38 00:02:29,850 --> 00:02:33,870 Goldilocks distance from its parent star to have potentially have 39 00:02:33,890 --> 00:02:37,890 liquid water and now we've seen water vapor in its atmosphere. But that's not 40 00:02:37,910 --> 00:02:42,090 the only characteristic of a planet that might be habitable. 41 00:02:42,110 --> 00:02:46,100 We also are concerned that the star that this planet is 42 00:02:46,120 --> 00:02:50,120 orbiting is probably very active. It's what we call a dwarf star. 43 00:02:50,140 --> 00:02:54,160 It may have some flaring. The planet is closer to its star 44 00:02:54,180 --> 00:02:58,190 than Earth is to our bigger sun. And it means that there might be heavy 45 00:02:58,210 --> 00:03:02,200 radiation coming on this planet which might it difficult for advanced life 46 00:03:02,220 --> 00:03:06,240 to thrive. We just don't know. But we've made this next step 47 00:03:06,260 --> 00:03:10,240 now of finding a super Earth with water vapor in the atmosphere and that's 48 00:03:10,260 --> 00:03:14,260 an exciting step to make. 49 00:03:14,280 --> 00:03:18,280 [slate] 50 00:03:18,300 --> 00:03:22,470 Well thanks to telescopes 51 00:03:22,490 --> 00:03:26,660 both on the ground and telescopes in space such as 52 00:03:26,680 --> 00:03:30,660 NASA's Kepler Space Telescope we understand that planets 53 00:03:30,680 --> 00:03:34,680 are quiet common in our galaxy. In fact many, 54 00:03:34,700 --> 00:03:38,700 if not most stars have at least one planet. Now those planets may 55 00:03:38,720 --> 00:03:42,710 not be similar to planet Earth, but planets themselves seem to be common. 56 00:03:42,730 --> 00:03:46,750 And so it's likely that there are 57 00:03:46,770 --> 00:03:50,770 millions and possibly billions of Earth 58 00:03:50,790 --> 00:03:54,810 or super-Earth sized exoplanets in the galaxy or 59 00:03:54,830 --> 00:03:58,860 orbiting other stars but most of them are very far away and very difficult 60 00:03:58,880 --> 00:04:02,890 for us to learn any great details about those exoplanets. 61 00:04:02,910 --> 00:04:06,910 We're better off looking at the near-by stars to find 62 00:04:06,930 --> 00:04:11,090 details, and we're doing that with some other NASA facilities as well 63 00:04:11,110 --> 00:04:15,130 like the TESS mission which is looking at planets round very bright stars in our 64 00:04:15,150 --> 00:04:19,140 neighborhood around the sun. And this information all works together 65 00:04:19,160 --> 00:04:23,330 to tell us some of the details of some of these exoplanets. 66 00:04:23,350 --> 00:04:27,330 But we believe exoplanets are very common and even Earth-mass, 67 00:04:27,350 --> 00:04:31,330 Earth-sized planets are probably fairly common in our galaxy. 68 00:04:31,350 --> 00:04:35,330 [slate] 69 00:04:35,350 --> 00:04:39,340 [slate] 70 00:04:39,360 --> 00:04:43,380 This particular planet is 71 00:04:43,400 --> 00:04:47,410 110 light years away. That means it's taken over 72 00:04:47,430 --> 00:04:51,420 100 years for the light from that system just to even get to our Hubble 73 00:04:51,440 --> 00:04:55,440 Space Telescope. For us to travel there would take 74 00:04:55,460 --> 00:04:59,510 many lifetimes. We don't have the technology yet 75 00:04:59,530 --> 00:05:03,620 to actually send a probe or any kind of mission to this 76 00:05:03,640 --> 00:05:07,640 system. So the way we are studying is by 77 00:05:07,660 --> 00:05:11,640 receiving the light from the star as it kind of comes through 78 00:05:11,660 --> 00:05:15,640 the atmosphere around the exoplanet as the planet orbits in front of the star 79 00:05:15,660 --> 00:05:19,670 And we can see what's in that atmosphere based on what the atmosphere absorbs from 80 00:05:19,690 --> 00:05:23,700 that starlight. That is the way we can explore this system with our current technology. 81 00:05:23,720 --> 00:05:27,700 [slate] 82 00:05:27,720 --> 00:05:31,750 [slate] 83 00:05:31,770 --> 00:05:35,750 Well we've used the Hubble Space Telescope 84 00:05:35,770 --> 00:05:39,810 for all of its mission basically to study planets 85 00:05:39,830 --> 00:05:43,880 in our own solar system. We have beautiful images of Jupiter 86 00:05:43,900 --> 00:05:47,910 and Saturn and we've also been studying their atmospheres. 87 00:05:47,930 --> 00:05:51,930 And the characteristics of their moons. But we're now using 88 00:05:51,950 --> 00:05:55,940 Hubble also to look at other star systems 89 00:05:55,960 --> 00:06:00,000 and their planets. When Hubble was launched back in 1990 we weren't even sure that 90 00:06:00,020 --> 00:06:04,060 there were abundance of planets around other stars. Hubble was not designed 91 00:06:04,080 --> 00:06:08,090 to do this kind of work. And yet now scientists are using Hubble to 92 00:06:08,110 --> 00:06:12,110 study the very compositions of atmospheres of planets orbiting 93 00:06:12,130 --> 00:06:16,130 other stars. We'd like to know how other planetary systems 94 00:06:16,150 --> 00:06:20,150 compare to our own solar system. And that is something Hubble is terrific at. 95 00:06:20,170 --> 00:06:24,170 [slate] 96 00:06:24,190 --> 00:06:28,190 [slate] The Hubble Space Telescope 97 00:06:28,210 --> 00:06:32,190 is turning 30 years old in 2020 98 00:06:32,210 --> 00:06:36,210 and it is in fantastic shape. The team 99 00:06:36,230 --> 00:06:40,210 of engineers and technical experts that oversee Hubble 100 00:06:40,230 --> 00:06:44,280 have kept it operating in tip top shape and we're grateful to astronauts who 101 00:06:44,300 --> 00:06:48,290 have returned to the Hubble several times over its mission to keep it 102 00:06:48,310 --> 00:06:52,290 refreshed with good instruments and supporting capabilities 103 00:06:52,310 --> 00:06:56,300 So right now we are getting the strongest science from the Hubble Space Telescope 104 00:06:56,320 --> 00:07:00,320 than we ever have and we expect that to continue for quite 105 00:07:00,340 --> 00:07:04,360 a few more years to come. In fact we're looking forward to an overlap of 106 00:07:04,380 --> 00:07:08,380 some years between the Hubble Space Telescope and the new James Webb 107 00:07:08,400 --> 00:07:12,410 Space Telescope that will launch in 2021. These telescopes 108 00:07:12,430 --> 00:07:16,430 will be complementary in terms of the information we get from them 109 00:07:16,450 --> 00:07:20,470 covering a spectrum of light all the way from what Hubble can see in the ultraviolet 110 00:07:20,490 --> 00:07:24,530 and visible parts of the light spectrum to the infrared 111 00:07:24,550 --> 00:07:28,590 part of the spectrum that Hubble can see and also the James Webb 112 00:07:28,610 --> 00:07:32,620 much deeper into the infrared part of the light spectrum. This teaches us 113 00:07:32,640 --> 00:07:36,620 a lot about exoplanets, about the stars 114 00:07:36,640 --> 00:07:40,650 that they orbit. About how they form and even about 115 00:07:40,670 --> 00:07:44,661 very distant star systems as well.