Why we need to go back to Mars
-
0:00 - 0:05I want to talk about 4.6 billion years of history
-
0:05 - 0:07in 18 minutes.
-
0:07 - 0:10That's 300 million years per minute.
-
0:10 - 0:14Let's start with the first photograph NASA obtained
-
0:14 - 0:16of planet Mars.
-
0:16 - 0:18This is fly-by, Mariner IV.
-
0:18 - 0:21It was taken in 1965.
-
0:21 - 0:23When this picture appeared,
-
0:23 - 0:26that well-known scientific journal,
-
0:26 - 0:29The New York Times, wrote in its editorial,
-
0:29 - 0:31"Mars is uninteresting.
-
0:31 - 0:34It's a dead world. NASA should not spend
-
0:34 - 0:38any time or effort studying Mars anymore."
-
0:38 - 0:40Fortunately, our leaders in Washington
-
0:40 - 0:42at NASA headquarters knew better
-
0:42 - 0:46and we began a very extensive study
-
0:46 - 0:48of the red planet.
-
0:48 - 0:52One of the key questions in all of science,
-
0:52 - 0:54"Is there life outside of Earth?"
-
0:54 - 0:58I believe that Mars is the most likely target
-
0:58 - 1:00for life outside the Earth.
-
1:00 - 1:02I'm going to show you in a few minutes
-
1:02 - 1:04some amazing measurements that suggest
-
1:04 - 1:06there may be life on Mars.
-
1:06 - 1:10But let me start with a Viking photograph.
-
1:10 - 1:14This is a composite taken by Viking in 1976.
-
1:14 - 1:17Viking was developed and managed at the
-
1:17 - 1:19NASA Langley Research Center.
-
1:19 - 1:23We sent two orbiters and two landers in the summer of 1976.
-
1:23 - 1:27We had four spacecraft, two around Mars,
-
1:27 - 1:29two on the surface --
-
1:29 - 1:31an amazing accomplishment.
-
1:31 - 1:33This is the first photograph taken from
-
1:33 - 1:35the surface of any planet.
-
1:35 - 1:37This is a Viking Lander photograph
-
1:37 - 1:39of the surface of Mars.
-
1:39 - 1:42And yes, the red planet is red.
-
1:42 - 1:45Mars is half the size of the Earth,
-
1:45 - 1:48but because two-thirds of the Earth is covered by water,
-
1:48 - 1:51the land area on Mars
-
1:51 - 1:53is comparable to the land area on Earth.
-
1:53 - 1:58So, Mars is a pretty big place even though it's half the size.
-
1:58 - 2:01We have obtained topographic measurements
-
2:01 - 2:03of the surface of Mars. We understand
-
2:03 - 2:05the elevation differences.
-
2:05 - 2:07We know a lot about Mars.
-
2:07 - 2:11Mars has the largest volcano in the solar system,
-
2:11 - 2:13Olympus Mons.
-
2:13 - 2:15Mars has the Grand Canyon
-
2:15 - 2:18of the solar system, Valles Marineris.
-
2:18 - 2:20Very, very interesting planet.
-
2:20 - 2:23Mars has the largest
-
2:23 - 2:25impact crater in the solar system,
-
2:25 - 2:27Hellas Basin.
-
2:27 - 2:29This is 2,000 miles across.
-
2:29 - 2:31If you happened to be on Mars
-
2:31 - 2:33when this impactor hit,
-
2:33 - 2:35it was a really bad day on Mars.
-
2:35 - 2:37(Laughter)
-
2:37 - 2:39This is Olympus Mons.
-
2:39 - 2:42This is bigger than the state of Arizona.
-
2:42 - 2:44Volcanoes are important, because volcanoes
-
2:44 - 2:47produce atmospheres and they produce oceans.
-
2:47 - 2:50We're looking at Valles Marineris,
-
2:50 - 2:52the largest canyon in the solar system,
-
2:52 - 2:55superimposed on a map of the United States,
-
2:55 - 2:573,000 miles across.
-
2:57 - 3:00One of the most intriguing features about Mars,
-
3:00 - 3:02the National Academy of Science says
-
3:02 - 3:05one of the 10 major mysteries of the space age,
-
3:05 - 3:08is why certain areas of Mars
-
3:08 - 3:10are so highly magnetized.
-
3:10 - 3:12We call this crustal magnetism.
-
3:12 - 3:15There are regions on Mars, where, for some reason --
-
3:15 - 3:18we don't understand why at this point --
-
3:18 - 3:21the surface is very, very highly magnetized.
-
3:21 - 3:23Is there water on Mars?
-
3:23 - 3:26The answer is no, there is no liquid water
-
3:26 - 3:28on the surface of Mars today.
-
3:28 - 3:30But there is intriguing evidence
-
3:30 - 3:33that suggests that the early history of Mars
-
3:33 - 3:35there may have been rivers
-
3:35 - 3:38and fast flowing water.
-
3:38 - 3:40Today Mars is very very dry.
-
3:40 - 3:43We believe there's some water in the polar caps,
-
3:43 - 3:46there are polar caps of North Pole and South Pole.
-
3:46 - 3:48Here are some recent images.
-
3:48 - 3:51This is from Spirit and Opportunity.
-
3:51 - 3:53These images that show at one time,
-
3:53 - 3:57there was very fast flowing water on the surface of Mars.
-
3:57 - 3:59Why is water important? Water is important
-
3:59 - 4:03because if you want life you have to have water.
-
4:03 - 4:05Water is the key ingredient
-
4:05 - 4:09in the evolution, the origin of life on a planet.
-
4:09 - 4:11Here is some picture of Antarctica
-
4:11 - 4:14and a picture of Olympus Mons,
-
4:14 - 4:16very similar features, glaciers.
-
4:16 - 4:18So, this is frozen water.
-
4:18 - 4:21This is ice water on Mars.
-
4:21 - 4:24This is my favorite picture. This was just taken a few weeks ago.
-
4:24 - 4:26It has not been seen publicly.
-
4:26 - 4:29This is European space agency
-
4:29 - 4:31Mars Express, image of a crater on Mars
-
4:31 - 4:33and in the middle of the crater
-
4:33 - 4:36we have liquid water, we have ice.
-
4:36 - 4:38Very intriguing photograph.
-
4:38 - 4:42We now believe that in the early history of Mars,
-
4:42 - 4:45which is 4.6 billion years ago,
-
4:45 - 4:494.6 billion years ago, Mars was very Earth-like.
-
4:49 - 4:52Mars had rivers, Mars had lakes,
-
4:52 - 4:56but more important Mars had planetary-scale oceans.
-
4:56 - 5:00We believe that the oceans were in the northern hemisphere,
-
5:00 - 5:02and this area in blue,
-
5:02 - 5:05which shows a depression of about four miles,
-
5:05 - 5:08was the ancient ocean area
-
5:08 - 5:10on the surface of Mars.
-
5:10 - 5:13Where did the ocean's worth of water on Mars go?
-
5:13 - 5:15Well, we have an idea.
-
5:15 - 5:18This is a measurement we obtained a few years ago
-
5:18 - 5:22from a Mars-orbiting satellite called Odyssey.
-
5:22 - 5:24Sub-surface water on Mars,
-
5:24 - 5:27frozen in the form of ice.
-
5:27 - 5:30And this shows the percent. If it's a blueish color,
-
5:30 - 5:33it means 16 percent by weight.
-
5:33 - 5:35Sixteen percent, by weight, of the interior
-
5:35 - 5:38contains frozen water, or ice.
-
5:38 - 5:41So, there is a lot of water below the surface.
-
5:41 - 5:45The most intriguing and puzzling measurement,
-
5:45 - 5:48in my opinion, we've obtained of Mars,
-
5:48 - 5:51was released earlier this year
-
5:51 - 5:54in the magazine Science.
-
5:54 - 5:58And what we're looking at is the presence of the gas methane,
-
5:58 - 6:02CH4, in the atmosphere of Mars.
-
6:02 - 6:06And you can see there are three distinct regions of methane.
-
6:06 - 6:08Why is methane important?
-
6:08 - 6:10Because on Earth, almost all --
-
6:10 - 6:1399.9 percent -- of the methane
-
6:13 - 6:16is produced by living systems,
-
6:16 - 6:20not little green men, but microscopic life
-
6:20 - 6:22below the surface or at the surface.
-
6:22 - 6:24We now have evidence
-
6:24 - 6:27that methane is in the atmosphere of Mars,
-
6:27 - 6:29a gas that, on Earth,
-
6:29 - 6:31is biogenic in origin,
-
6:31 - 6:33produced by living systems.
-
6:33 - 6:37These are the three plumes: A, B1, B2.
-
6:37 - 6:40And this is the terrain it appears over,
-
6:40 - 6:43and we know from geological studies
-
6:43 - 6:47that these regions are the oldest regions on Mars.
-
6:47 - 6:49In fact, the Earth and Mars
-
6:49 - 6:53are both 4.6 billion years old.
-
6:53 - 6:57The oldest rock on Earth is only 3.6 billion.
-
6:57 - 7:00The reason there is a billion-year gap
-
7:00 - 7:02in our geological understanding
-
7:02 - 7:04is because of plate tectonics,
-
7:04 - 7:07The crust of the Earth has been recycled.
-
7:07 - 7:09We have no geological record prior
-
7:09 - 7:11for the first billion years.
-
7:11 - 7:13That record exists on Mars.
-
7:13 - 7:15And this terrain that we're looking at
-
7:15 - 7:19dates back to 4.6 billion years
-
7:19 - 7:22when Earth and Mars were formed.
-
7:22 - 7:24It was a Tuesday.
-
7:24 - 7:26(Laughter)
-
7:26 - 7:28This is a map that shows
-
7:28 - 7:32where we've put our spacecraft on the surface of Mars.
-
7:32 - 7:35Here is Viking I, Viking II.
-
7:35 - 7:38This is Opportunity. This is Spirit.
-
7:38 - 7:40This is Mars Pathfinder. This is Phoenix,
-
7:40 - 7:42we just put two years ago.
-
7:42 - 7:46Notice all of our rovers and all of our landers
-
7:46 - 7:48have gone to the northern hemisphere.
-
7:48 - 7:51That's because the northern hemisphere
-
7:51 - 7:53is the region of the ancient
-
7:53 - 7:55ocean basin.
-
7:55 - 7:57There aren't many craters.
-
7:57 - 8:00And that's because the water protected the basin
-
8:00 - 8:04from being impacted by asteroids and meteorites.
-
8:04 - 8:07But look in the southern hemisphere.
-
8:07 - 8:09In the southern hemisphere there are impact craters,
-
8:09 - 8:11there are volcanic craters.
-
8:11 - 8:13Here's Hellas Basin,
-
8:13 - 8:16a very very different place, geologically.
-
8:16 - 8:19Look where the methane is, the methane is in a very
-
8:19 - 8:23rough terrain area.
-
8:23 - 8:25What is the best way to unravel
-
8:25 - 8:28the mysteries on Mars that exist?
-
8:28 - 8:32We asked this question 10 years ago.
-
8:32 - 8:35We invited 10 of the top Mars scientists
-
8:35 - 8:39to the Langley Research Center for two days.
-
8:39 - 8:41We addressed on the board
-
8:41 - 8:44the major questions that have not been answered.
-
8:44 - 8:47And we spent two days deciding
-
8:47 - 8:50how to best answer this question.
-
8:50 - 8:53And the result of our meeting
-
8:53 - 8:59was a robotic rocket-powered airplane we call ARES.
-
8:59 - 9:03It's an Aerial Regional-scale Environmental Surveyor.
-
9:03 - 9:05There's a model of ARES here.
-
9:05 - 9:08This is a 20-percent scale model.
-
9:08 - 9:12This airplane was designed at the Langley Research Center.
-
9:12 - 9:14If any place in the world
-
9:14 - 9:16can build an airplane to fly on Mars,
-
9:16 - 9:18it's the Langley Research Center,
-
9:18 - 9:20for almost 100 years
-
9:20 - 9:23a leading center of aeronautics in the world.
-
9:23 - 9:26We fly about a mile above the surface.
-
9:26 - 9:28We cover hundreds of miles,
-
9:28 - 9:31and we fly about 450 miles an hour.
-
9:31 - 9:34We can do things that rovers can't do
-
9:34 - 9:36and landers can't do:
-
9:36 - 9:39We can fly above mountains, volcanoes, impact craters;
-
9:39 - 9:41we fly over valleys;
-
9:41 - 9:43we can fly over surface magnetism,
-
9:43 - 9:46the polar caps, subsurface water;
-
9:46 - 9:48and we can search for life on Mars.
-
9:48 - 9:50But, of equal importance,
-
9:50 - 9:53as we fly through the atmosphere of Mars,
-
9:53 - 9:56we transmit that journey,
-
9:56 - 9:59the first flight of an airplane outside of the Earth,
-
9:59 - 10:02we transmit those images back to Earth.
-
10:02 - 10:06And our goal is to inspire the American public
-
10:06 - 10:09who is paying for this mission through tax dollars.
-
10:09 - 10:12But more important we will
-
10:12 - 10:15inspire the next generation of scientists,
-
10:15 - 10:18technologists, engineers and mathematicians.
-
10:18 - 10:22And that's a critical area of national security
-
10:22 - 10:26and economic vitality, to make sure
-
10:26 - 10:28we produce the next generation
-
10:28 - 10:31of scientists, engineers, mathematicians and technologists.
-
10:31 - 10:34This is what ARES looks like
-
10:34 - 10:36as it flies over Mars.
-
10:36 - 10:38We preprogram it.
-
10:38 - 10:40We will fly where the methane is.
-
10:40 - 10:43We will have instruments aboard the plane
-
10:43 - 10:46that will sample, every three minutes, the atmosphere of Mars.
-
10:46 - 10:48We will look for methane
-
10:48 - 10:50as well as other gasses
-
10:50 - 10:52produced by living systems.
-
10:52 - 10:56We will pinpoint where these gases emanate from,
-
10:56 - 10:59because we can measure the gradient where it comes from,
-
10:59 - 11:02and there, we can direct the next mission
-
11:02 - 11:05to land right in that area.
-
11:05 - 11:08How do we transport an airplane to Mars?
-
11:08 - 11:11In two words, very carefully.
-
11:11 - 11:15The problem is we don't fly it to Mars,
-
11:15 - 11:18we put it in a spacecraft
-
11:18 - 11:20and we send it to Mars.
-
11:20 - 11:22The problem is the spacecraft's
-
11:22 - 11:26largest diameter is nine feet;
-
11:26 - 11:31ARES is 21-foot wingspan, 17 feet long.
-
11:31 - 11:33How do we get it to Mars?
-
11:33 - 11:35We fold it,
-
11:35 - 11:38and we transport it in a spacecraft.
-
11:38 - 11:41And we have it in something called an aeroshell.
-
11:41 - 11:43This is how we do it.
-
11:43 - 11:47And we have a little video that describes the sequence.
-
11:47 - 11:52Video: Seven, six. Green board. Five, four, three, two, one.
-
11:52 - 11:55Main engine start, and liftoff.
-
12:05 - 12:08Joel Levine: This is a launch from the Kennedy Space Center in Florida.
-
12:14 - 12:16This is the spacecraft taking nine months
-
12:16 - 12:18to get to Mars.
-
12:18 - 12:21It enters the atmosphere of Mars.
-
12:21 - 12:23A lot of heating,
-
12:26 - 12:28frictional heating. It's going 18 thousand miles an hour.
-
12:28 - 12:32A parachute opens up to slow it down.
-
12:32 - 12:35The thermal tiles fall off.
-
12:35 - 12:38The airplane is exposed to the atmosphere for the first time.
-
12:38 - 12:41It unfolds.
-
12:41 - 12:43The rocket engine begins.
-
12:50 - 12:53We believe that in a one-hour flight
-
12:53 - 12:56we can rewrite the textbook on Mars
-
12:56 - 12:59by making high-resolution measurements of the atmosphere,
-
12:59 - 13:02looking for gases of biogenic origin,
-
13:02 - 13:05looking for gases of volcanic origin,
-
13:05 - 13:08studying the surface, studying the magnetism
-
13:08 - 13:10on the surface, which we don't understand,
-
13:10 - 13:13as well as about a dozen other areas.
-
13:13 - 13:15Practice makes perfect.
-
13:15 - 13:17How do we know we can do it?
-
13:17 - 13:21Because we have tested ARES model,
-
13:21 - 13:24several models in a half a dozen wind tunnels
-
13:24 - 13:27at the NASA Langley Research Center for eight years,
-
13:27 - 13:29under Mars conditions.
-
13:29 - 13:31And, of equal importance
-
13:31 - 13:35is, we test ARES in the Earth's atmosphere,
-
13:35 - 13:38at 100,000 feet,
-
13:38 - 13:41which is comparable to the density and pressure
-
13:41 - 13:44of the atmosphere on Mars where we'll fly.
-
13:44 - 13:47Now, 100,000 feet, if you fly cross-country to Los Angeles,
-
13:47 - 13:49you fly 37,000 feet.
-
13:49 - 13:52We do our tests at 100,000 feet.
-
13:52 - 13:55And I want to show you one of our tests.
-
13:55 - 13:57This is a half-scale model.
-
13:57 - 13:59This is a high-altitude helium balloon.
-
13:59 - 14:02This is over Tilamook, Oregon.
-
14:02 - 14:06We put the folded airplane on the balloon --
-
14:06 - 14:08it took about three hours to get up there --
-
14:08 - 14:10and then we released it on command
-
14:10 - 14:12at 103,000 feet,
-
14:12 - 14:16and we deploy the airplane and everything works perfectly.
-
14:16 - 14:18And we've done
-
14:18 - 14:20high-altitude and low-altitude tests,
-
14:20 - 14:25just to perfect this technique.
-
14:25 - 14:27We're ready to go.
-
14:27 - 14:29I have a scale model here.
-
14:29 - 14:31But we have a full-scale model
-
14:31 - 14:34in storage at the NASA Langley Research Center.
-
14:34 - 14:38We're ready to go. All we need is a check from NASA headquarters
-
14:38 - 14:40(Laughter)
-
14:40 - 14:42to cover the costs.
-
14:42 - 14:45I'm prepared to donate my honorarium for today's talk
-
14:45 - 14:47for this mission.
-
14:47 - 14:51There's actually no honorarium for anyone for this thing.
-
14:51 - 14:53This is the ARES team;
-
14:53 - 14:57we have about 150 scientists, engineers;
-
14:57 - 14:59where we're working with Jet Propulsion Laboratory,
-
14:59 - 15:01Goddard Space Flight Center,
-
15:01 - 15:04Ames Research Center and half a dozen major universities
-
15:04 - 15:06and corporations in developing this.
-
15:06 - 15:13It's a large effort. It's all at NASA Langley Research Center.
-
15:13 - 15:16And let me conclude by saying
-
15:16 - 15:18not too far from here,
-
15:18 - 15:21right down the road in Kittyhawk, North Carolina,
-
15:21 - 15:23a little more than 100 years ago
-
15:23 - 15:25history was made
-
15:25 - 15:28when we had the first powered flight of an airplane on Earth.
-
15:28 - 15:30We are on the verge right now
-
15:30 - 15:33to make the first flight of an airplane
-
15:33 - 15:35outside the Earth's atmosphere.
-
15:35 - 15:38We are prepared to fly this on Mars,
-
15:38 - 15:40rewrite the textbook about Mars.
-
15:40 - 15:43If you're interested in more information,
-
15:43 - 15:46we have a website that describes this exciting
-
15:46 - 15:49and intriguing mission, and why we want to do it.
-
15:49 - 15:51Thank you very much.
-
15:51 - 15:54(Applause)
- Title:
- Why we need to go back to Mars
- Speaker:
- Joel Levine
- Description:
-
At TEDxNASA, planetary scientist Joel Levine shows some intriguing -- and puzzling -- new discoveries about Mars: craters full of ice, traces of ancient oceans, and compelling hints at the presence, sometime in the past, of life. He makes the case for going back to Mars to find out more.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 15:54
TED edited English subtitles for Why we need to go back to Mars | ||
TED added a translation |