1 00:00:00,020 --> 00:00:04,100 Narrator: In the last few decades 2 00:00:04,100 --> 00:00:08,210 we have found thousands of worlds around other stars. 3 00:00:08,210 --> 00:00:12,330 A new NASA astrophysics mission will help us find 4 00:00:12,330 --> 00:00:16,520 many more. Elisa Quintana: TESS, the Transiting Exoplanet Survey Satellite, 5 00:00:16,520 --> 00:00:20,590 is NASA's newest exoplanet mission. It's being led out of MIT, 6 00:00:20,590 --> 00:00:24,680 and it's going to find thousands of new planets orbiting bright nearby stars. 7 00:00:24,680 --> 00:00:28,800 And it's going to build upon the legacy of the Kepler mission, 8 00:00:28,800 --> 00:00:32,950 only it's going focus on nearby bright stars that are sprinkled across the whole sky, 9 00:00:32,950 --> 00:00:37,040 and it's going to help us answer a really important question. And that is: which of 10 00:00:37,040 --> 00:00:40,620 our nearest stellar neighbors has planets? Narrator: During its 11 00:00:40,620 --> 00:00:45,320 two year survey, TESS will look for signs of planets, ranging 12 00:00:45,320 --> 00:00:49,200 from Earth size, to giants larger than Jupiter. 13 00:00:49,200 --> 00:00:53,600 TESS will search for these new worlds, or exoplanets, using 14 00:00:53,610 --> 00:00:57,730 transits, the same method as the Kepler mission. 15 00:00:57,730 --> 00:01:01,830 As a planet passes in front of its star, it blocks some of the 16 00:01:01,830 --> 00:01:05,990 light, causing a slight drop in brightness. 17 00:01:05,990 --> 00:01:10,070 TESS can detect those subtle dips, and even use them to 18 00:01:10,070 --> 00:01:14,150 determine some basic features of the planets, such as their size, 19 00:01:14,150 --> 00:01:18,320 and orbit. Each of TESS's cameras has 20 00:01:18,320 --> 00:01:22,440 a 16.8-megapixel sensor, covering a 24-degree square-- 21 00:01:22,440 --> 00:01:26,530 large enough to contain an entire constellation. 22 00:01:26,530 --> 00:01:30,680 TESS has four of these cameras, arranged to view a vertical strip of 23 00:01:30,680 --> 00:01:34,810 the sky, called an observation sector. George Ricker: The coverage of 24 00:01:34,810 --> 00:01:38,930 the TESS cameras is unprecidented in terms of the amount of sky 25 00:01:38,930 --> 00:01:43,140 that they can actually see at any given time and also their 26 00:01:43,140 --> 00:01:47,320 ability to cover such a broad portion of the sky. 27 00:01:47,320 --> 00:01:51,520 The types of targets that TESS will allow us to find, 28 00:01:51,520 --> 00:01:55,580 will enclose essentially all of the bright nearby stars. 29 00:01:55,580 --> 00:01:59,640 Narrator: TESS will watch each observation sector for about 27 days 30 00:01:59,640 --> 00:02:03,750 before rotating to next one, covering first the south, and then the north 31 00:02:03,750 --> 00:02:07,870 to eventually build a map of 85 percent of the sky. 32 00:02:07,870 --> 00:02:11,950 This coverage--about 350 times 33 00:02:11,950 --> 00:02:16,060 what Kepler first observed--will make TESS the first 34 00:02:16,060 --> 00:02:20,180 exoplanet mission to survey almost the entire sky. 35 00:02:20,180 --> 00:02:24,360 TESS will fly in a highly elliptical orbit that maximizes 36 00:02:24,360 --> 00:02:28,490 the amount of sky the spacecraft can image and is carefully timed with the orbit 37 00:02:28,490 --> 00:02:32,490 of the moon. It will spend most of each 13.7 day 38 00:02:32,490 --> 00:02:36,640 orbit collecting data, and then, as it passes closer to Earth, 39 00:02:36,640 --> 00:02:40,750 it will transmit that data to the ground. 40 00:02:40,750 --> 00:02:44,870 Because TESS's observation sectors overlap, it will have 41 00:02:44,870 --> 00:02:48,910 an area near the pole under constant observation. 42 00:02:48,910 --> 00:02:53,000 This region is easily monitored by the James Webb Space Telescope, 43 00:02:53,000 --> 00:02:57,120 which allows the two missions to work together to first find, and then 44 00:02:57,120 --> 00:03:01,240 carefully study exoplanets. Since most of the exoplanets 45 00:03:01,240 --> 00:03:05,360 found by TESS will orbit bright stars, missions like Webb will be 46 00:03:05,360 --> 00:03:09,560 able to measure the spectra of starlight absorbed by the planets' atmospheres, 47 00:03:09,560 --> 00:03:13,740 which can indicate what they're made of. Ground-based measurements 48 00:03:13,740 --> 00:03:17,810 of the TESS Exoplanets can determine their masses. Combining 49 00:03:17,810 --> 00:03:21,950 the masses with TESS's size measurements reveals densities, allowing 50 00:03:21,950 --> 00:03:26,100 scientists to better understand the exoplanets' compositions. 51 00:03:26,100 --> 00:03:30,180 Jennifer Burt: The thing that we're really excited about with TESS is the way that it'll actually build 52 00:03:30,180 --> 00:03:34,290 on the momentum that we started with Kepler. So TESS is going to take that same 53 00:03:34,290 --> 00:03:38,430 search approach, but apply it to the vast majority of the sky, which still hasn't 54 00:03:38,430 --> 00:03:42,520 really been looked at in detail when searching for exoplanets. And by focusing 55 00:03:42,520 --> 00:03:46,700 especially on planets that orbit bright nearby stars, TESS allows us to start looking 56 00:03:46,700 --> 00:03:50,810 at things like composition and atmospheric makeup, and that'll then be crucial when we 57 00:03:50,810 --> 00:03:54,870 want to start looking around stars that are even further away and in deeper parts of the galaxy as well. 58 00:03:54,870 --> 00:03:59,030 Narrator: TESS is the vanguard of a new 59 00:03:59,030 --> 00:04:03,160 era of exoplanet study, and will forever expand 60 00:04:03,160 --> 00:04:07,220 our understanding of worlds beyond our own. 61 00:04:07,220 --> 00:04:11,310 ♪Music♪ 62 00:04:11,310 --> 00:04:15,420 ♪Music♪ 63 00:04:15,420 --> 00:04:19,530 [Beeping] 64 00:04:19,530 --> 00:04:26,333 [Beeping]