1 00:00:00,040 --> 00:00:04,070 Voice Off Screen: So the evolution of Mars from a warm and wet planet to the cold and dry desert 2 00:00:04,070 --> 00:00:08,120 we see today is one of our solar system's biggest secrets 3 00:00:08,120 --> 00:00:12,190 and shedding a little bit of light on that secret is NASA's MAVEN mission. 4 00:00:12,190 --> 00:00:16,260 Here to tell us more about it from NASA's Goddard Space Flight Center in 5 00:00:16,260 --> 00:00:20,350 Greenbelt, Maryland is NASA Scientist Dr. Jared Espley. Thank you 6 00:00:20,350 --> 00:00:21,390 for joining us. 7 00:00:21,390 --> 00:00:22,600 Thank You. 8 00:00:22,600 --> 00:00:26,140 Voice Off Screen: So MAVEN is returning some exciting results on the martian atmosphere 9 00:00:26,140 --> 00:00:28,120 what are we seeing? 10 00:00:28,120 --> 00:00:32,500 So MAVEN is NASA's most recent Mars mission, its actually in orbit around the planet 11 00:00:32,500 --> 00:00:36,520 right now. It's main purpose is to investigate what caused 12 00:00:36,520 --> 00:00:40,530 most of the martian atmosphere to disappear over time. 13 00:00:40,530 --> 00:00:44,590 What I really mean by that is that we know that ancient Mars was a warm, wet 14 00:00:44,590 --> 00:00:48,610 and possibly habitable environment. Whereas modern Mars is 15 00:00:48,610 --> 00:00:52,670 clearly a cold, dry, and desolate place. So the question we'd like to answer is 16 00:00:52,670 --> 00:00:56,770 "how did that come to be?" and with MAVEN we have the instruments to actually directly observe 17 00:00:56,770 --> 00:01:00,890 this. We're seeing that the solar wind, this thin stream of gas flowing out 18 00:01:00,890 --> 00:01:05,010 from the sun, is actually washing over the martian atmosphere and blowing it away 19 00:01:05,010 --> 00:01:09,040 bit by bit so that over billions of years its been lost in an interplanetary 20 00:01:09,040 --> 00:01:11,650 space forever. 21 00:01:11,650 --> 00:01:13,080 Voice Off Screen: Fascinating 22 00:01:13,080 --> 00:01:17,150 So what role does atmosphereic loss play in Mars' ability to 23 00:01:17,150 --> 00:01:18,900 support life? 24 00:01:18,900 --> 00:01:23,600 So everywhere that we find with life on Earth its associated with water. 25 00:01:23,600 --> 00:01:25,330 So the question really comes down to 26 00:01:25,330 --> 00:01:29,460 "Where can we find the water at Mars?" and so as 27 00:01:29,460 --> 00:01:33,490 we talked about we actually think that Mars used to have a lot of liquid water on it 28 00:01:33,490 --> 00:01:37,520 surface, but we see only today dry riverbeds, dry lakes, 29 00:01:37,520 --> 00:01:41,550 dry gullies so something had to have happened to cause the atmosphere 30 00:01:41,550 --> 00:01:45,590 and the water to go away, so that water could have either flown off 31 00:01:45,590 --> 00:01:49,660 into space, been driven away into space, or gone into the subsurface. 32 00:01:49,660 --> 00:01:53,690 And with MAVEN we're starting to see it clearly was driven off into space at least 33 00:01:53,690 --> 00:01:57,780 a part. And so we're able to start addressing that question of where the water went. 34 00:01:57,780 --> 00:02:01,900 Where the atmosphere went, and therefore the potential for life at Mars. 35 00:02:01,900 --> 00:02:06,070 Voice Off Screen: Now what is MAVEN telling us about the impact of the Sun 36 00:02:06,070 --> 00:02:08,140 on the martian climate? 37 00:02:08,140 --> 00:02:10,100 So like we just talked about the main culprit 38 00:02:10,100 --> 00:02:14,150 we think at the moment is the solar wind to drive away the martian atmosphere 39 00:02:14,150 --> 00:02:18,210 but one of the really interesting things of course is the Sun itself has these beautiful 40 00:02:18,210 --> 00:02:22,290 solar storms, these filamentary archs 41 00:02:22,290 --> 00:02:26,360 of high energy gas that come flowing off of the Sun that makes these solar 42 00:02:26,360 --> 00:02:30,470 storms. And as these storms wash over the planet we wonder if they would be 43 00:02:30,470 --> 00:02:34,610 they would be able to create even greater atmospheric loss than just a steady state solar 44 00:02:34,610 --> 00:02:38,630 wind. So we're interested in studying the steady state solar wind and comparing it 45 00:02:38,630 --> 00:02:42,680 to what the atmosphere does when the huge solar storms wash over the planet. 46 00:02:42,680 --> 00:02:46,780 Voice Off Screen: Interesting. So now a recent NASA discovery has found 47 00:02:46,780 --> 00:02:50,850 water on Mars' surface. So how do MAVEN's results help us 48 00:02:50,850 --> 00:02:54,970 understand what has actually happened to water on the planet? 49 00:02:54,970 --> 00:02:59,100 Right, so that was a really interesting result because it showed that there was thin films 50 00:02:59,100 --> 00:03:03,130 of water that occur seasonally on Mars today. So liquid water today 51 00:03:03,130 --> 00:03:07,160 on the surface of the planet. And then MAVEN is interested in the big picture question 52 00:03:07,160 --> 00:03:11,180 of how water has evolved over time at Mars at a planet 53 00:03:11,180 --> 00:03:15,200 ary scale. What happened to the water that carved the dry river beds that we see? 54 00:03:15,200 --> 00:03:19,260 And so together with the results of tiny bits of liquid water available today 55 00:03:19,260 --> 00:03:23,350 and it's history of water that we're getting from MAVEN and how it's been lost to space 56 00:03:23,350 --> 00:03:27,450 mostly, which is starting to answer the big picture question of the evolution of 57 00:03:27,450 --> 00:03:29,970 water at Mars. 58 00:03:29,970 --> 00:03:31,580 Voice Off Screen: Where can we go to learn more 59 00:03:31,580 --> 00:03:34,000 about MAVEN and NASA's future with Mars? 60 00:03:34,000 --> 00:03:35,600 You can learn more at 61 00:03:35,600 --> 00:03:39,680 nasa.gov/maven, there's all kinds of really cool science visualizations 62 00:03:39,680 --> 00:03:43,730 and interesting videos about our mission and the results that we're getting. 63 00:03:43,730 --> 00:03:47,790 Voice Off Screen: Dr. Jared Espley thank you so much for joining us. 64 00:03:47,790 --> 00:03:49,029 Thank you.