1 00:00:00,020 --> 00:00:04,060 Voice Off Screen: Our cosmic neighborhood just got a little more crowded, NASA just announced it has 2 00:00:04,060 --> 00:00:08,100 discovered seven Earth sized planets orbiting a star that's only 3 00:00:08,100 --> 00:00:12,110 forty light years away. The findings from NASA's Spitzer 4 00:00:12,110 --> 00:00:16,290 Space Telescope also found that three of these planets are in the habitable zone, where 5 00:00:16,290 --> 00:00:20,300 liquid water might flow on it's surface. This is very exciting news 6 00:00:20,300 --> 00:00:24,310 and here to tell us more about this result and what's next is 7 00:00:24,310 --> 00:00:28,320 Dr. Paul Hertz at NASA's Goddard Space Flight Center, thanks for joining us. 8 00:00:28,320 --> 00:00:32,330 Dr. Paul Hertz: You're welcome. Voice Off Screen: So start by telling us about these results 9 00:00:32,330 --> 00:00:36,510 Dr. Paul Hertz: Well yesterday we announced that we have discovered seven Earth sized planets orbiting the same star 10 00:00:36,510 --> 00:00:40,520 and three of these planets are the right distance from the star so 11 00:00:40,520 --> 00:00:44,520 their temperatures are such that they could support liquid water on the surface. 12 00:00:44,520 --> 00:00:48,710 Now this star is not like our Sun, it's only one tenth as large and is much 13 00:00:48,710 --> 00:00:52,720 fainter, so these seven planets are squeezed around that star 14 00:00:52,720 --> 00:00:56,730 closer than Mercury is to the Sun, but even so 15 00:00:56,730 --> 00:01:00,850 they're getting the right amount of light so that they could support life as we know it 16 00:01:00,850 --> 00:01:04,850 were that life to be there. 17 00:01:04,850 --> 00:01:08,850 Voice Off Screen: Forty light years away, I mean it's still far but it's relatively close in cosmic terms 18 00:01:08,850 --> 00:01:13,050 can you talk about how we're able to tell if any 19 00:01:13,050 --> 00:01:17,060 of these planets might be similar to Earth? Dr. Paul Hertz: Sure, astronomers have 20 00:01:17,060 --> 00:01:21,070 come up with this very clever way of studying planets around other stars. 21 00:01:21,070 --> 00:01:25,090 As the planet orbits the star, it passes in front of the star blocking out 22 00:01:25,090 --> 00:01:29,280 a tiny amount of light. By measuring how much light that blocks 23 00:01:29,280 --> 00:01:33,290 out, we know how big the planet is; by measuring how long it is until it 24 00:01:33,290 --> 00:01:37,300 blocks out light again we can measure how long it's year is, and that tells 25 00:01:37,300 --> 00:01:41,300 us how far from the star it is and how much sunlight it gets. So this tells us 26 00:01:41,300 --> 00:01:45,310 how big it is, it's Earth size, tells us how much sunlight it gets 27 00:01:45,310 --> 00:01:49,310 It's Earth-like temperature that puts it firmly in the area of planets that 28 00:01:49,310 --> 00:01:53,330 might be able to have water on their surface. 29 00:01:53,330 --> 00:01:57,510 Voice Off Screen: Now it wasn't that long ago really that we didn't even know if there were 30 00:01:57,510 --> 00:02:01,520 planets orbiting other stars. We figured there probably were 31 00:02:01,520 --> 00:02:05,530 be, can you talk about how some of NASA's 32 00:02:05,530 --> 00:02:09,610 space telescopes, Hubble and Spitzer, are 33 00:02:09,610 --> 00:02:13,700 you know, looking at these exoplanets and determining their atmospheres? 34 00:02:13,700 --> 00:02:17,710 Dr. Paul Hertz: Well now that we know those planets are there we can use the NASA 35 00:02:17,710 --> 00:02:21,900 space telescopes to study them, so we're studying these planets with Hubble and Spitzer 36 00:02:21,900 --> 00:02:26,000 looking for the light as it passes through those 37 00:02:26,000 --> 00:02:30,030 star's atmospheres and that tells us something about those planets. Next year 38 00:02:30,030 --> 00:02:34,200 we'll be launching the TESS satellite and that's going 39 00:02:34,200 --> 00:02:38,270 to scan the entire sky looking for more stars and more planets 40 00:02:38,270 --> 00:02:42,450 like the ones we announced yesterday. And at the end of next year we'll be 41 00:02:42,450 --> 00:02:46,460 launching the James Webb Space Telescope, the largest space telescope 42 00:02:46,460 --> 00:02:50,580 that NASA has ever launched with its very large mirror and exquisite optics 43 00:02:50,580 --> 00:02:54,660 we'll be able to study these planets and planets around other stars 44 00:02:54,660 --> 00:02:58,660 in much more detail than we have before and we'll be able to study 45 00:02:58,660 --> 00:03:02,670 the planet's atmospheres in great detail looking for molecules 46 00:03:02,670 --> 00:03:06,850 in those atmospheres that on Earth indicate the presence of life. 47 00:03:06,850 --> 00:03:11,040 Molecules like Oxygen, Water, Methane. 48 00:03:11,040 --> 00:03:15,150 Voice Off Screen: Tell us a little about, you know as far as this 49 00:03:15,150 --> 00:03:19,160 discovery, talk about what that was like when you 50 00:03:19,160 --> 00:03:23,340 heard there were seven Earth sized planets orbiting 51 00:03:23,340 --> 00:03:27,350 this relatively close star. Dr. Paul Hertz: Well when I was a 52 00:03:27,350 --> 00:03:31,540 astronomy student, we didn't know of any planets around stars other than our own 53 00:03:31,540 --> 00:03:35,560 Sun. I was skeptical like many other astronomers 54 00:03:35,560 --> 00:03:39,740 that we would ever be able to discover and study them even if 55 00:03:39,740 --> 00:03:43,940 they were there. Twenty years ago we were able to discover the very first exoplanet 56 00:03:43,940 --> 00:03:48,130 and in twenty years we've found over five thousand of them. 57 00:03:48,130 --> 00:03:52,150 So we've come to understand that they're out there and we can study them. 58 00:03:52,150 --> 00:03:56,160 But yesterday's announcement with seven Earth-sized planets in the same, 59 00:03:56,160 --> 00:04:00,190 around the same star means that, not only does every star probably 60 00:04:00,190 --> 00:04:04,210 have a planet, every star probably has many planets 61 00:04:04,210 --> 00:04:08,390 that are rocky and in the habitable zone meaning there are billions 62 00:04:08,390 --> 00:04:12,490 of places where life might arise. 63 00:04:12,490 --> 00:04:16,500 We'll start looking at them but the fact that there are so many of them just 64 00:04:16,500 --> 00:04:20,510 boggles the imagination about what are the chances that life is out there? 65 00:04:20,510 --> 00:04:24,520 Voice Off Screen: This is very, very exciting, where can we find more about 66 00:04:24,520 --> 00:04:28,590 the recent results and any updates as we go forward? 67 00:04:28,590 --> 00:04:32,590 Dr. Paul Hertz: Well NASA makes all of it's discoveries about exoplanets available at our website 68 00:04:32,590 --> 00:04:37,928 nasa.gov/exoplanets