Why we need to go back to Mars | Joel Levine | TEDxNASA

In this talk, 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.

I want to talk about two planets

the title is really,
"A tale of two planets" -

Earth and Mars.

I want to talk about
4.6 billion years of history

in 18 minutes.

That's 300 million years per minute.

Let's begin the talk.

Let's start with the first photograph
NASA obtained

of planet Mars.

This is fly-by, Mariner IV.

It was taken in 1965.

When this picture appeared,

that well-known scientific journal,

The New York Times,
wrote in its editorial,

"Mars is uninteresting.

It's a dead world.
NASA should not spend

any time or effort studying Mars anymore."

Fortunately, our leaders in Washington

at NASA headquarters knew better

and we began a very extensive study

of the red planet.

One of the key questions
in all of science,

"Is there life outside of Earth?"

I believe that Mars
is the most likely target

for life outside the Earth.

I'm going to show you in a few minutes

some amazing measurements that suggest

there may be life on Mars.

But let me start with a Viking photograph.

This is a composite
taken by Viking in 1976.

Viking was developed and managed

at the NASA Langley Research Center.

We sent two orbiters and two landers
in the summer of 1976.

We had four spacecraft, two around Mars,

two on the surface -

an amazing accomplishment.

This is the first photograph taken

from the surface of any planet.

This is a Viking Lander photograph

of the surface of Mars.

And yes, the red planet is red.

Mars is half the size of the Earth,

but because two-thirds
of the Earth is covered by water,

the land area on Mars

is comparable to the land area on Earth.

So, Mars is a pretty big place
even though it's half the size.

We have obtained topographic measurements

of the surface of Mars.

We understand the elevation differences.

We know a lot about Mars.

Mars has the largest volcano
in the solar system,

Olympus Mons.

Mars has the Grand Canyon

of the solar system, Valles Marineris.

Very, very interesting planet.

Mars has the largest

impact crater in the solar system,

Hellas Basin.

This is 2,000 miles across.

If you happened to be on Mars

when this impactor hit,

it was a really bad day on Mars.

(Laughter)

This is Olympus Mons.

This is bigger than the state of Arizona.

Volcanoes are important, because volcanoes

produce atmospheres
and they produce oceans.

We're looking at Valles Marineris,

the largest canyon in the solar system,

superimposed on a map
of the United States,

3,000 miles across.

One of the most intriguing features
about Mars,

the National Academy of Science says

one of the 10 major mysteries
of the space age,

is why certain areas of Mars

are so highly magnetized.

We call this crustal magnetism.

There are regions on Mars, where,
for some reason -

we don't understand why at this point -

the surface is very,
very highly magnetized.

Crustal magnetism.

Is there water on Mars?

The answer is no, there is no liquid water

on the surface of Mars today.

But there is intriguing evidence

that suggests
that in early history of Mars

there may have been rivers

and fast flowing water.

Today Mars is very very dry.

We believe there's some water
in the polar caps,

there are polar caps
of North Pole and South Pole.

Here are some recent images.

This is from Spirit and Opportunity.

These images that show at one time,

there was very fast flowing water
on the surface of Mars.

Why is water important?
Water is important

because if you want life
you have to have water.

Water is the key ingredient

in the evolution,
the origin of life on a planet.

Here is some picture of Antarctica

and a picture of Olympus Mons,

very similar features, glaciers.

So, this is frozen water.

This is ice water on Mars.

This is my favorite picture.
This was just taken a few weeks ago.

It has not been seen publicly.

This is European space agency

Mars Express, image of a crater on Mars

and in the middle of the crater

we have liquid water, we have ice.

Very intriguing photograph.

We now believe
that in the early history of Mars,

which is 4.6 billion years ago,

4.6 billion years ago,
Mars was very Earth-like.

Mars had rivers, Mars had lakes,

but more important
Mars had planetary-scale oceans.

We believe that the oceans
were in the northern hemisphere,

and this area in blue,

which shows a depression
of about four miles,

was the ancient ocean area

on the surface of Mars.

Where did the ocean's worth
of water on Mars go?

Well, we have an idea.

This is a measurement
we obtained a few years ago

from a Mars-orbiting satellite
called Odyssey.

Sub-surface water on Mars,

frozen in the form of ice.

And this shows the percent.
If it's a blueish color,

it means 16 percent by weight.

Sixteen percent, by weight,
of the interior

contains frozen water, or ice.

So, there is a lot of water
below the surface.

The most intriguing
and puzzling measurement,

in my opinion, we've obtained of Mars,

was released earlier this year

in the magazine Science.

And what we're looking at
is the presence of the gas methane,

CH4, in the atmosphere of Mars.

And you can see there are three
distinct regions of methane.

Why is methane important?

Because on Earth, almost all -

99.9 percent - of the methane

is produced by living systems,

not little green men, but microscopic life

below the surface or at the surface.

We now have evidence

that methane is in the atmosphere of Mars,

a gas that, on Earth,

is biogenic in origin,

produced by living systems.

These are the three plumes: A, B1, B2.

And this is the terrain it appears over,

and we know from geological studies

that these regions
are the oldest regions on Mars.

In fact, the Earth and Mars

are both 4.6 billion years old.

The oldest rock on Earth
is only 3.6 billion.

The reason there is a billion-year gap

in our geological understanding

is because of plate tectonics,

The crust of the Earth has been recycled.

So the oldest rock on Earth

is a billion years after the Earth formed.

We have no geological record prior

for the first billion years.

That record exists on Mars.

And this terrain that we're looking at

dates back to 4.6 billion years

when Earth and Mars were formed.

It was a Tuesday.

(Laughter)

This is a map that shows

where we've put our spacecraft
on the surface of Mars.

Here is Viking I, Viking II.

This is Opportunity. This is Spirit.

This is Mars Pathfinder.

This is Phoenix,
we just put two years ago.

Notice all of our rovers
and all of our landers

have gone to the northern hemisphere.

That's because the northern hemisphere

is the region of the ancient

ocean basin.

There aren't many craters.

And that's because the water
protected the basin

from being impacted
by asteroids and meteorites.

But look in the southern hemisphere.

In the southern hemisphere
there are impact craters,

there are volcanic craters.

Here's Hellas Basin,

a very very different place, geologically.

Look where the methane is,
the methane is in a very

rough terrain area.

What is the best way to unravel

the mysteries on Mars that exist?

We asked this question 10 years ago.

We invited 10 of the top Mars scientists

to the Langley Research Center
for two days.

We addressed on the board

the major questions
that have not been answered.

And we spent two days deciding

how to best answer this question.

And the result of our meeting -

two day meeting, on the best way
to solve these questions on Mars -

was a robotic rocket-powered airplane
we call ARES.

It's an Aerial Regional-scale
Environmental Surveyor.

There's a model of ARES here.

No speaker has made mention to it before,

but it's been here
since last night when I brought it,

This is a 20-percent scale model.

This airplane was designed
at the Langley Research Center.

If any place in the world

can build an airplane to fly on Mars,

it's the Langley Research Center,

for almost 100 years

a leading center of aeronautics
in the world.

We fly about a mile above the surface.

We cover hundreds of miles,

and we fly about 450 miles an hour.

We can do things that rovers can't do

and landers can't do:

We can fly above mountains,
volcanoes, impact craters;

we fly over valleys;

we can fly over surface magnetism,

the polar caps, subsurface water;

and we can search for life on Mars.

But, of equal importance,

as we fly through the atmosphere of Mars,

we transmit that journey,

the first flight of an airplane
outside of the Earth,

we transmit those images back to Earth.

And our goal is to inspire
the American public

who is paying for this mission
through tax dollars.

But more important we will

inspire the next generation of scientists,

technologists, engineers
and mathematicians.

And that's a critical area
of national security

and economic vitality, to make sure

we produce the next generation

of scientists, engineers,
mathematicians and technologists.

This is what ARES looks like

as it flies over Mars.

We preprogram it.

We will fly where the methane is.

We will have instruments aboard the plane

that will sample, every three minutes,
the atmosphere of Mars.

We will look for methane

as well as other gasses

produced by living systems.

We will pinpoint
where these gases emanate from,

because we can measure the gradient
where it comes from,

and there, we can direct the next mission

to land right in that area.

How do we transport an airplane to Mars?

In two words, very carefully.

The problem is we don't fly it to Mars,

we put it in a spacecraft

and we send it to Mars.

The problem is the spacecraft's

largest diameter is nine feet;

ARES is 21-foot wingspan, 17 feet long.

How do we get it to Mars?

We fold it,

and we transport it in a spacecraft.

And we have it in something
called an aeroshell.

This is how we do it.

And we have a little video
that describes the sequence.

Video: Seven, six. Green board.
Five, four, three, two, one.

Main engine start, and liftoff.

Joel Levine: This is a launch
from the Kennedy Space Center in Florida.

This is the spacecraft taking nine months

to get to Mars.

It enters the atmosphere of Mars.

A lot of heating, frictional heating.

It's going 18 thousand miles an hour.

A parachute opens up to slow it down.

The thermal tiles fall off.

The airplane is exposed
to the atmosphere for the first time.

It unfolds.

The rocket engine begins.

We believe that in a one-hour flight

we can rewrite the textbook on Mars

by making high-resolution measurements
of the atmosphere,

looking for gases of biogenic origin,

looking for gases of volcanic origin,

studying the surface,
studying the magnetism

on the surface, which we don't understand,

as well as about a dozen other areas.

Practice makes perfect.

How do we know we can do it?

Because we have tested ARES model,

several models
in a half a dozen wind tunnels

at the NASA Langley Research Center
for eight years,

under Mars conditions.

And, of equal importance

is, we test ARES
in the Earth's atmosphere,

at 100,000 feet,

which is comparable
to the density and pressure

of the atmosphere on Mars where we'll fly.

Now, 100,000 feet, if you fly
cross-country to Los Angeles,

you fly 37,000 feet.

We do our tests at 100,000 feet.

And I want to show you one of our tests.

This is a half-scale model.

This is a high-altitude helium balloon.

This is over Tilamook, Oregon.

We put the folded airplane
on the balloon -

it took about three hours
to get up there -

and then we released it on command

at 103,000 feet,

and we deploy the airplane
and everything works perfectly.

And we've done

high-altitude and low-altitude tests,

just to perfect this technique.

We're ready to go.

I have a scale model here.

But we have a full-scale model

in storage at the NASA
Langley Research Center.

We're ready to go.

All we need is a check
from NASA headquarters

(Laughter)

to cover the costs.

I'm prepared to donate
my honorarium for today's talk

for this mission.

There's actually no honorarium
for anyone for this thing.

This is the ARES team;

we have about 150 scientists, engineers;

where we're working
with Jet Propulsion Laboratory,

Goddard Space Flight Center,

Ames Research Center
and half a dozen major universities

and corporations in developing this.

It's a large effort.

It's all led
at NASA Langley Research Center.

And let me conclude by saying

not too far from here,

right down the road in Kittyhawk,
North Carolina,

a little more than 100 years ago

history was made

when we had the first powered flight
of an airplane on Earth.

And in Anna McGowan's talk,

you heard about
where we're going in the next 100 years.

We are on the verge right now

to make the first flight of an airplane

outside the Earth's atmosphere.

We are prepared to fly this on Mars,

rewrite the textbook about Mars.

If you're interested in more information,

we have a website
that describes this exciting

and intriguing mission,
and why we want to do it.

Thank you very much.

(Applause)