1 00:00:00,000 --> 00:00:08,880 For hundreds of years, humans have dreamed of exploring the planet Mars. 2 00:00:08,880 --> 00:00:13,040 One important reason for this is that, other than Earth, Mars is the planet with the most 3 00:00:13,040 --> 00:00:15,600 hospitable climate in our solar system. 4 00:00:15,600 --> 00:00:20,920 The climate on Mars is so hospitable, in fact, that many scientists believe that liquid water 5 00:00:20,920 --> 00:00:25,520 may have once flowed over its surface, harboring primitive bacterial life. 6 00:00:25,520 --> 00:00:30,160 In an effort to investigate these intriguing possibilities, NASA's planned several new 7 00:00:30,160 --> 00:00:32,720 Mars exploration missions. 8 00:00:32,720 --> 00:00:36,920 NASA planners hope these missions will help explain many unanswered questions about the 9 00:00:36,920 --> 00:00:40,840 Red Planet and how those answers will affect us here on Earth. 10 00:00:40,840 --> 00:00:46,240 I spoke with Preysan Desai from NASA Langley Research Center to find out more. 11 00:00:46,240 --> 00:00:50,960 In mid-2003, two Mars exploration rovers will be launched to explore the surface of Mars. 12 00:00:50,960 --> 00:00:54,360 You may remember the Pathfinder mission from a few years ago. 13 00:00:54,360 --> 00:00:56,920 These are very similar, but have some major differences. 14 00:00:56,920 --> 00:01:01,080 The Pathfinder mission had a lander, which acted as a base station, and a small rover, 15 00:01:01,080 --> 00:01:03,200 which was about a foot and a half in length. 16 00:01:03,200 --> 00:01:07,920 The 2003 rovers have many more instruments and will be able to traverse much longer distances 17 00:01:07,920 --> 00:01:09,640 on the surface of Mars. 18 00:01:09,640 --> 00:01:14,840 These new rovers will act like mobile field geologists. 19 00:01:14,840 --> 00:01:17,240 This mission is actually very exciting compared to previous missions. 20 00:01:17,240 --> 00:01:20,880 For the first time, the rovers will be able to go much greater distances away from the 21 00:01:20,880 --> 00:01:25,720 lander, and for the first time, we could also go to a hill on top of it and see what's 22 00:01:25,720 --> 00:01:26,720 over it. 23 00:01:26,720 --> 00:01:30,340 And so, we would be able to cover a lot more different areas and see different geological 24 00:01:30,340 --> 00:01:35,720 features to try to get a better understanding of how Mars is evolving in those regions. 25 00:01:35,720 --> 00:01:38,920 Preysan, what's the process of getting the rovers to Mars? 26 00:01:38,920 --> 00:01:44,000 Well, Tonya, the rovers will be launched on Delta rockets in June and July of 2003. 27 00:01:44,000 --> 00:01:48,160 The rockets will provide the appropriate speed needed to get the spacecraft to go to 28 00:01:48,160 --> 00:01:49,160 Mars. 29 00:01:49,160 --> 00:01:57,320 The spacecraft consists of a cruise stage, which supply the communications and power 30 00:01:57,320 --> 00:02:10,320 during the seven-month journey to Mars, and a lander, which has the rover inside it. 31 00:02:10,320 --> 00:02:15,040 Upon arrival at Mars in January 2004, the landers are separated and enter the Martian 32 00:02:15,040 --> 00:02:16,040 atmosphere. 33 00:02:16,040 --> 00:02:20,800 Once the lander enters the Martian atmosphere, the aeroshell design will slow the entry from 34 00:02:20,800 --> 00:02:29,000 12,000 miles per hour to about 900 miles per hour. 35 00:02:29,000 --> 00:02:48,160 A parachute will then deploy, further slowing the spacecraft. 36 00:02:48,160 --> 00:02:53,920 Then airbags will inflate around the craft to cushion the landing. 37 00:02:53,920 --> 00:03:04,840 At about 600 feet above the surface, retro-rockets will fire, slowing the craft even further. 38 00:03:04,840 --> 00:03:09,520 Once the spacecraft stops rolling, the airbags will deflate and pedals will open up, bringing 39 00:03:09,520 --> 00:03:12,280 the lander to an upright position. 40 00:03:12,280 --> 00:03:16,920 Since the rovers carry all of their instruments on board, they'll be able to start exploring 41 00:03:16,920 --> 00:03:23,600 the planet almost immediately without having to stay close to the lander. 42 00:03:23,600 --> 00:03:24,920 How will the rovers be commanded? 43 00:03:24,920 --> 00:03:27,360 Will they be driven by remote control from Earth? 44 00:03:27,360 --> 00:03:32,200 Actually, the controllers from the Earth will only command the rovers to specific soil and 45 00:03:32,200 --> 00:03:33,200 rock targets. 46 00:03:33,200 --> 00:03:36,280 It'll be up to the rovers to find their own way to get there. 47 00:03:36,280 --> 00:03:39,840 The reason we have to do this is because a signal from Earth takes too long to get to 48 00:03:39,840 --> 00:03:43,120 Mars to have us operate them by remote control. 49 00:03:43,120 --> 00:03:46,660 As a result, the rovers must be able to operate autonomously. 50 00:03:46,660 --> 00:03:50,960 We will decide, based on information we get from the cameras and instruments that are 51 00:03:50,960 --> 00:03:54,400 sitting on the rover, where are good sites to go to and then command the rovers to go 52 00:03:54,400 --> 00:03:55,400 there. 53 00:03:55,400 --> 00:03:59,080 We hope the rovers will be able to travel up to a half a mile from the landing site. 54 00:03:59,080 --> 00:04:03,480 Okay, so once the rover gets to a rock of interest, how will it examine it? 55 00:04:03,480 --> 00:04:07,480 The rovers have many different instruments on there that allow us to examine the rocks 56 00:04:07,480 --> 00:04:09,680 down to the microscopic level. 57 00:04:09,680 --> 00:04:12,760 Once we analyze this type of information, we can tell a lot of different things about 58 00:04:12,760 --> 00:04:18,900 the rock themselves, like their mineralogy, elemental chemistry, their surface texture. 59 00:04:18,900 --> 00:04:22,620 This type of information will give us evidence of ancient environmental conditions and the 60 00:04:22,620 --> 00:04:25,660 possibility of some type of biological activity occurring. 61 00:04:25,660 --> 00:04:30,260 Recent satellite images of Mars show geologic features like channels, which support the 62 00:04:30,260 --> 00:04:33,140 theory that liquid water once flowed over the surface. 63 00:04:33,140 --> 00:04:37,540 Today, the Martian temperature is too low and the atmosphere too thin for liquid water 64 00:04:37,540 --> 00:04:42,300 to exist on the surface, but many scientists believe that liquid water may still exist 65 00:04:42,300 --> 00:04:46,180 below the surface of Mars where temperatures are not as harsh. 66 00:04:46,180 --> 00:04:51,660 If the rovers find convincing evidence of liquid water on Mars, then it's also possible 67 00:04:51,660 --> 00:04:54,860 they may find proof of life on Mars as well. 68 00:04:54,860 --> 00:04:59,580 There's a lot of evidence that there's frozen water just below the surface of Mars and a 69 00:04:59,580 --> 00:05:03,420 lot of these missions that we're trying to go to Mars in the next few years is trying 70 00:05:03,420 --> 00:05:08,180 to get a better understanding of how much water is there and is it in the liquid form 71 00:05:08,180 --> 00:05:09,300 near the surface somewhere. 72 00:05:09,300 --> 00:05:12,460 Three billion years ago, Mars and Earth were very much alike. 73 00:05:12,460 --> 00:05:17,700 Mars was, at that time, much wetter and much warmer than it is now and something has happened. 74 00:05:17,700 --> 00:05:21,500 So by trying to get a better understanding of how Mars' environment has evolved, it will 75 00:05:21,500 --> 00:05:24,860 give us a better understanding of potentially how the Earth's environment would evolve and 76 00:05:24,860 --> 00:05:28,140 give us an idea of how it's going to change in the future. 77 00:05:28,140 --> 00:05:32,660 So by studying Mars, it may be able to tell where our future is headed in this space? 78 00:05:32,660 --> 00:05:33,660 Exactly. 79 00:05:33,660 --> 00:05:37,080 The reason we are exploring Mars and other places in the solar system for that matter 80 00:05:37,080 --> 00:05:40,680 is to help answer two fundamental questions. 81 00:05:40,680 --> 00:05:45,480 One, to explain the formation and evolution of our solar system and the Earth within it 82 00:05:45,480 --> 00:05:50,080 and two, to seek the origins of life and its existence beyond the Earth. 83 00:05:50,080 --> 00:05:54,480 During the next decade, Mars will be the solar system's most popular travel destination. 84 00:05:54,480 --> 00:05:58,120 There are plans for nearly a dozen Mars missions being planned by three countries, the United 85 00:05:58,120 --> 00:06:01,160 States, Russia and Japan. 86 00:06:01,160 --> 00:06:04,880 Coming up, a new device developed by NASA might help parents and caregivers keep an 87 00:06:04,880 --> 00:06:06,660 electronic eye on their children. 88 00:06:06,660 --> 00:06:10,680 But first, did you know that the Viking 1 spacecraft was the first craft to land on 89 00:06:10,680 --> 00:06:14,280 the Martian surface on July 20, 1976? 90 00:06:14,280 --> 00:06:19,240 With its companion craft, Viking 2, the two landers analyzed atmospheric and weather conditions, 91 00:06:19,240 --> 00:06:25,200 collected soil samples and took over 56,000 pictures of the planet's surface.