1 00:00:00,000 --> 00:00:07,000 Most scientists dismiss the idea of alien life forms as utterly impossible. 2 00:00:07,000 --> 00:00:13,000 But recently, a startling discovery in outer space has even some of the country's most ardent skeptics 3 00:00:13,000 --> 00:00:16,000 reconsidering their position. 4 00:00:16,000 --> 00:00:23,000 For the first time in history, we may finally have proof that there is a spark of life beyond Earth. 5 00:00:23,000 --> 00:00:31,000 We use our intellect to try to understand this universe and to try to understand our place in the universe. 6 00:00:31,000 --> 00:00:34,000 Why do we exist? 7 00:00:34,000 --> 00:00:37,000 The origin of life on Earth. 8 00:00:37,000 --> 00:00:41,000 It's a question that astronomers try to answer by looking at the cosmos. 9 00:00:41,000 --> 00:00:48,000 And recently, one tiny piece of the puzzle fell into place when NASA astronomers used the Hubble telescope 10 00:00:48,000 --> 00:00:51,000 to confirm the existence of black holes. 11 00:00:51,000 --> 00:00:59,000 And the reason this is important is that black holes are more than just some science fiction, fantastic phenomena. 12 00:00:59,000 --> 00:01:03,000 It's our first glimpse of the edge of the universe as we know it. 13 00:01:03,000 --> 00:01:10,000 As a science writer for the San Francisco Examiner, Key Davidson is continually revising his definition of space. 14 00:01:10,000 --> 00:01:18,000 It's important to remember that a black hole is something that defies space and time as we intuitively think of them. 15 00:01:18,000 --> 00:01:21,000 We tend to think of space and time as things that are absolute. 16 00:01:21,000 --> 00:01:27,000 The gravitational pull is so strong that nothing can escape from it, not even a beam of light. 17 00:01:27,000 --> 00:01:29,000 That is why we call it black hole. 18 00:01:29,000 --> 00:01:35,000 According to Hubble project specialist Duccio Machetto, a black hole's extraordinary gravitational pull 19 00:01:35,000 --> 00:01:40,000 has the ability to capture the essence of the cosmos. 20 00:01:40,000 --> 00:01:45,000 We begin to get a better view, a better understanding of how the universe as a whole works, 21 00:01:45,000 --> 00:01:51,000 of how galaxies are formed, how stars are formed, how they evolve and how we came to be. 22 00:01:51,000 --> 00:02:00,000 Think of a black hole as a cosmic factory where raw materials are sucked in and then transformed into stars, planets and galaxies. 23 00:02:00,000 --> 00:02:05,000 If this is true, then perhaps life in outer space can be created in the same way. 24 00:02:05,000 --> 00:02:13,000 And recently one of the raw materials of life has been discovered floating in space, an amino acid called glycine. 25 00:02:13,000 --> 00:02:16,000 So it would be sort of like finding a brick floating around in space. 26 00:02:16,000 --> 00:02:19,000 From that you can infer the existence of brick houses in outer space. 27 00:02:19,000 --> 00:02:26,000 Now we don't know for sure that this glycine means that larger amino acid structures are forming in space, 28 00:02:26,000 --> 00:02:32,000 but it's a clue that the formation of the building blocks of life is a routine thing in the universe. 29 00:02:32,000 --> 00:02:39,000 If the building blocks of life are to be found routinely in space, can we presume that Earth is the only living planet? 30 00:02:39,000 --> 00:02:42,000 According to many scientists, no. 31 00:02:42,000 --> 00:02:47,000 Earth is the best prospect in the solar system at the moment for another life form. 32 00:02:47,000 --> 00:02:54,000 Planetary scientist Jay Malage theorizes that catastrophic collisions between celestial bodies millions of years ago 33 00:02:54,000 --> 00:02:58,000 could have sent enormous chunks of our planet hurtling into space. 34 00:02:58,000 --> 00:03:06,000 For example, the impact that killed the dinosaurs 65 million years ago left a crater almost 200 kilometers in diameter. 35 00:03:06,000 --> 00:03:10,000 That very well may have blown rocks off the surface of the Earth entirely, 36 00:03:10,000 --> 00:03:17,000 and those rocks could potentially carry microorganisms that would then be transported through space and fall on Mars. 37 00:03:17,000 --> 00:03:20,000 And if these planetary fragments carried life from Earth to Mars, 38 00:03:20,000 --> 00:03:23,000 Ian's ago, could the reverse also be true? 39 00:03:23,000 --> 00:03:30,000 We have in our laboratories and museums chunks of Mars that have come to the Earth. 40 00:03:30,000 --> 00:03:34,000 Maybe terrestrial life has its roots on Mars. 41 00:03:34,000 --> 00:03:39,000 Maybe we're all evolved Martians. 42 00:03:39,000 --> 00:03:43,000 But for life to exist, there must be water. 43 00:03:43,000 --> 00:03:48,000 Geologist Jeff Cargo has found evidence that water once flowed on Mars. 44 00:03:48,000 --> 00:03:51,000 I would say that Mars is extremely water rich. 45 00:03:51,000 --> 00:03:54,000 Now, most of its water is in the form of ice. 46 00:03:54,000 --> 00:03:56,000 It's a cryogenic planet today. 47 00:03:56,000 --> 00:04:02,000 There are certainly abundant indications that liquid water flowed on the surface. 48 00:04:02,000 --> 00:04:09,000 And some astrogeologists believe that microbes in a state of cryogenic suspension exist under Martian ice today. 49 00:04:09,000 --> 00:04:18,000 Life is very imaginative, and it finds ways of adapting to an extraordinary range of environments. 50 00:04:18,000 --> 00:04:22,000 We find living creatures in hot springs in Yellowstone. 51 00:04:22,000 --> 00:04:26,000 We find them living beneath the ice of Antarctica. 52 00:04:26,000 --> 00:04:35,000 And I have no doubt that given enough time, life forms could exist on Mars just as they exist on the Earth. 53 00:04:35,000 --> 00:04:44,000 Less than 100 years ago, a nanosecond in cosmic time, we rode in horse-drawn buggies and depended on the Pony Express. 54 00:04:44,000 --> 00:04:48,000 Today we're sending a robot to mine the surface of Mars. 55 00:04:48,000 --> 00:04:55,000 It may be sooner than we think before we have the ability to make contact with alien life forms we can only dream about today. 56 00:04:56,000 --> 00:04:58,000 Thank you.