CARTER EMMART: Good afternoon.
This is Carter Emmart.
I'm Carter Emmart
and I'm the Director
of Astrovisualization
for the American
Museum of Natural History.
And it's wonderful
to have you all
join us again here in this
time where we're all at home.
And hopefully, we can take
you through an exciting day.
We're going to start off here
at our blue planet earth.
We investigated this last
week using our software
OpenSpace, which is
freely available.
But we're going to go to Mars.
Today, we're going to go
to the red planet, which
is half the size of earth.
And joining me today is my
friend and colleague Jackie
Faherty.
Jackie, would you like
to say hello please.
JACKIE FAHERTY: Hi, everybody.
I'm Jackie Faherty.
As Carter said, I'm an
astronomer at the museum.
And I'm going to be
monitoring the chat, which I
can see is already very active.
And trying to grab
your questions
to give me shout outs throughout
this live presentation
and giving them to Carter.
So give me your
best ones, and I'll
try and get all of them
answered as we go along.
CARTER EMMART: Great.
Well, Micah is
joining us as well.
He's our pilot today.
And as we moved
away from the Earth,
we saw the orbit of the
moon around the Earth.
And just as the
moon goes around us,
we go around the sun along
with the inner planets
of the solar system.
So first it's mercury.
Next out is Venus.
We're number three
with the blue orbit.
And then, number four is Mars.
And so Mars is a very
exciting destination
because it's excited
our imagination even
before telescopes.
When we could look at Mars up
in the sky we saw a red star.
It seemed to be moving.
The planets were called
the wandering stars
because they moved against
the background stars.
So as we approach Mars,
Micah is driving us.
Thanks, Micah.
We could slow up
a little bit here.
We're going to see that just
as with Earth having the moon.
And we just saw a trail
of where the moon is.
And of course, it was
a full moon last night.
It's exciting.
Is that here, we see
that Mars has two moons.
Deimos, the outer moon, and
the larger inner moon, Phobos.
But from right here, we
can see how Mars is this--
it's this reddish brown color.
And so this color,
which, of course, just
reduced this to like what
we see of Mars in the night
sky of being red.
The Chinese called
it the fire star.
That this redness comes from
the fact that it's brown.
It's reddish brown.
And what we understand
of this is that Mars
is covered with iron oxide.
Think of rust on a
nail, a rusty nail.
And so this rust color
is what makes Mars this--
what it looks like here.
Even through the best
telescopes on earth,
we could see images that were
about like what you see here.
That's why I wanted Micah
to stop just around here.
And Micah has a picture.
Micah, could we
bring up a picture
of the comparison
with a dust storm.
Because Mars has
seasons like Earth.
In the southern
summer on Mars, we
tend to get global dust storms.
And so the image on the
left we can see features.
And in fact, the
darkest feature there
that we see just to the right of
center is called Syrtis Major.
And we see the polar cap,
the southern polar cap there.
But by comparison,
the same part of Mars
that we're looking at,
if you look on the right,
you see during a
global dust storm.
And so Mars is
sometimes obliterated.
It's always been-- this is
the best kind of view we ever
had from Earth.
And this was taken
by my friend Damian
Peach, who does a beautiful job
as an amateur astronomer taking
these pictures.
So Micah, let's show
the next picture.
I'd like to show the
Hubble picture of Earth.
Of Earth, of Mars, sorry.
We're going to-- here's from
Earth, from orbiting Earth,
this is the best view that we
can get from the Hubble Space
Telescope.
And what we see is actually that
dark feature I was pointing to.
And the last picture
is over on the right.
And we can see there
are white clouds.
That's because that dark
feature stands up high.
And in fact, where
it's high, it tends
to make the flow
of the atmosphere
over it tends to make clouds.
And so we see those clouds.
And so Mars does have clouds.
It has dust storms.
But we're going to show you
now images from satellites
that have mapped Mars.
So let's just go back to our
open space please, Micah.
And here, we have Mars.
We're coming in.
And so it wasn't until we
went there in the 1960s
with our first spacecraft that
started to get close to Mars.
And they would just fly by and
they would take a few pictures.
We could see that Mars
had craters like the moon.
And so we're going to come
in and look at that first.
In the darker
lower portion here,
we're going to get closer.
We actually see the
Valles Marineris Canyon up
and toward the
left there on Mars.
We're going to talk about that
later and take an exciting fly
through.
But down just a lower center
upstream, we see these--
we see a large round impact.
And then, these are
circular craters that
are caused by asteroid impacts.
So the largest craters
we actually called
basins because they
are regional and huge.
Whereas, then these
large craters--
and then we have craters going
down to very, very small.
But these craters are,
literally, like about--
almost in the largest ones
here, about 100 miles across.
So we're coming in and
what we can see is--
Michah, can you actually
pan down a little bit.
I want to just stop here
for a second and just--
JACKIE FAHERTY: Carter,
we've got a question
[INTERPOSING VOICES]
CARTER EMMART: And I
want to take a question.
Micha, yeah, just roll
back a little bit.
Micah is actually doing
this is as I ask him to.
So we can see a dried riverbed.
That's it.
We can see that.
And that's called
Nirgal Vallis, it
flows into another
thing called Uzbol
that flows into that crater.
Thanks, Micah.
Because this shows--
unlike the moon,
this showed that there
was something happening
on Mars related to the
atmosphere that must have
had flowing water in the past.
Jackie, there was a question.
Thanks, sorry.
JACKIE FAHERTY: We're
flowing with however
we can get the best views here.
We had Eva Heineman
was asking about
are these real images or not.
But a good sub question
in here she also has is,
can you say what days
these images were taken?
CARTER EMMART:
Well, actually, it's
hard to say what days
these images are taken.
But the answer is yes.
Every one of these
pictures, they're
put together sort of like
a big puzzle of pictures.
And we know exactly
where the spacecraft is,
and they take the pictures.
And they have it right
down to the second
when the pictures are taken.
And what open space is doing
is taking various products
that NASA has put together,
like these large global maps.
Our friend Jay Dixon at
the California Institute
of Technology put
together this global map
at five meter resolution.
Five meters is about the size
of a garage for your car.
It's not as big as a house.
It's bigger than a car, but
it's smaller than a house.
But then, we have
really detailed
pictures that get down to about
the size of a soccer ball.
And that's what we're
looking at here.
These very high detailed
closeups show a river delta.
So what we're seeing here--
you see this fan shape that
comes in from the
left, and it fans out
and it meanders around.
What we're looking
at is the result
of this crater called
Eberswalde was flooded.
And so this used to be a lake.
And we have the evidence
in the rocks that we see.
So see all those
meandering forms.
And Micah, could we come
into the top one up there.
It's sort of-- let's proceed
forward if we could please.
And what we'll look
down on basically--
these stream meanders come
in and they turn around just
as we see in rivers on Earth.
And in fact,
sometimes they cut off
and they form a little
lake called an oxbow lake.
Well, instead of
this being a valley,
this is actually-- these
stand up in relief.
Actually, they stand up above
the terrain around them.
Micah, could we
look down at this.
That might help
us in just looking
at the general overall pattern.
And we could see
it branches out.
So what we're seeing is
this evidence of water.
Now, when this flooded, it
brought down a lot of cobbles--
cobblestones and bigger stones.
But also a lot of sand.
What happened is--
and the reason
that this is standing
up above the surrounding
area is the wind
on Mars eventually
blew away all the
fine sand and silt,
and left, basically,
the streams that
were defined by the heavier
material that came flowing in
and fanned out into this
delta of Eberswalde crater.
So what we see on Mars
are craters like the moon.
And then, we see
rivers like on Earth.
So Mars, in a way, is caught
between the earth, which
of course is the water planet.
We're 3/4 covered with oceans.
And the moon, which is very
dry, doesn't have an atmosphere.
JACKIE FAHERTY: Carter, question
on this too from Pat Fenan.
And the question is on why
there are so many meteors
hitting Mars.
If that's a bigger number
than Earth and the moon,
can you do that
compare and contrast?
CARTER EMMART: Yeah,
that's actually
a really important question,
and thanks for asking that.
As we move out here, we're going
to come across to a landing
site of Opportunity Rover.
But cratering we see
all over the moon.
The smooth areas on
the moon, the darker
features that we see a sort
of old man's face in the moon
or a rabbit in the
moon, those are
smoother as where
the moon was hit
so hard with a big
enough asteroid
that the lava flowed
up from underneath
and created new surface
that was smooth.
Well, we see the same
sorts of things on Mars
that we'll see in a bit.
But cratering we know--
we have less craters
on Earth now because
of weathering and erosion.
So with rain and so forth
it basically erodes away.
It softens out the craters.
And even coming in
here, we're coming
into an area called Meridiani.
And this was chosen
as a landing site
because of how these
craters are degraded.
And we thought from
a chemical signature
that we could see above from
previous satellite missions
that there was a signature
of hematite, which
is a mineral that we know
on Earth formed in lakes,
and after lakes
evaporate and go away.
And so we thought,
perhaps, this is a spot
where water may have been.
Well, we now know because
of the Opportunity Rover
that this was a lake.
It would flood and
then it would dry out.
But we see the
evidence for that.
Micah is bringing us into one
of these really detailed images.
And Micah, could you bring us
up to where Opportunity landed.
We're going to
come up to a crater
that we saw Victoria at
the bottom of the screen.
The names were given
to these craters.
And we also now see
Endurance crater, which
was the first sizeable crater.
It's about a football
field and a half
in diameter, this thing
that's coming up toward us.
But there's a smaller crater.
It's about 25 yards wide,
and we call it Eagle.
So if you're a golfer, you know
that if you hit a hole in one
that's called an eagle.
Well, what happened is this
rover wasn't programmed
to land in that crater.
It came down and
had a parachute.
And then they released it.
It had crash bags and it
rolled across the surface
and it rolled into Eagle crater.
Do you see that bull's
eye in the crater?
Micah, if we could come
a little closer that'd
be great OK, and also notice
how these round holes.
It's lighter material.
That's because the
dust has blown away
the bedrock that is exposed
by the cratering process.
So a meteor comes in,
hits, makes a hole,
and then it fills
with dark dust.
And so as we see.
So inside the crater is
basically the cocoon,
the structure around
the rover that came in
had the crash bags.
It opened up like a
flower and Opportunity
drove off and explored.
So I want Micah to take us
over to the parachute which
is over in the lower left.
We can actually see where
the parachute landed.
JACKIE FAHERTY: Carter, as
we go over to the parachute,
Emma wants to know,
you've named the rovers,
but who actually got
to name the rovers?
CARTER EMMART: Well, students
get to name the rovers.
And so NASA has put a call out.
And typically, elementary
school students
get to do name the rovers.
And so it's interesting.
The first rover we
had was Sojourner,
named after Sojourner Truth.
And so that was in 1997
with the Pathfinder mission.
And that was solar powered.
And it was small.
It was about the size of maybe
a coffee table with wheels.
And Spirit and Opportunity are
much bigger, solar powered.
And so Opportunity
and its sister rover
called Spirit were both
designed to last 90 days, just
three months.
Well, Opportunity
lasted a lot longer.
There's no place else like
NASA to get better mileage.
Opportunity lasted until 2018.
So it landed in 2004.
It was active for over 14
years of investigation.
Well, let's see where it went.
So first it went to Endeavor.
So let's fly over there to
Endeavor crater a little bit,
and then we'll fly to Victoria.
So Micah is lining us
up so we can do that.
And so if you want to--
OK, there you go.
We're going to line up.
I'll just mentioned again, the
winds on Mars, unlike the moon.
The moon doesn't
have an atmosphere.
It's too small.
The moon is half
the size of Mars.
Mars is half the size of Earth.
Mars has a thin atmosphere now.
And it's very cold.
But what we see with that
water like we saw in the delta
that we saw in Eberswalde
is that Mars used
to be a water world like Earth.
Of course, we're
the water world now.
So the big question is,
where did the water come from
and where did it go?
And Opportunity was
landed here because we
saw the evidence that this
was, in the past, a lake.
I'll get to the
question of where
the water comes from next.
But we're going to first
fly over to Victoria crater.
And--
JACKIE FAHERTY: Carter, as
we go to another related
question on this.
You mentioned Sojourner,
Spirit, Opportunity.
How many rovers-- this one comes
from Sylvia in Pennsylvania.
How many rovers are
currently on Mars?
And you can answer operational
or not operational.
CARTER EMMART: Oh no, that's--
I started to say it
and I get carried away.
So my apologies.
And Micah is actually flying
over some sand dunes right now.
So you can see that they
had to drive-through that.
So the first Rover was
Sojourner, and it was tiny.
But it proved what we could
do with a solar powered rover.
So we built Spirit
and Opportunity.
And now, unfortunately,
all three of those rovers
are no longer phoning home.
Even though just almost
two years ago now we
lost touch with Opportunity.
But we have Curiosity, which
is the size of a Mini Cooper.
It's big.
And it's actually powered
by a plutonium battery.
So we can actually weather
through global dust storms.
We saw that global dust
storm in the beginning.
If you're solar power and
you have a global dust storm
it gets dark.
And so that's not so good.
Micah is going to bring us in.
Can we come in
even closer, Micah.
This is the edge of a half mile
wide crater called Victoria.
And if we get in close
enough, we'll actually see--
I'm going to lean
in here to see it.
I see them.
If we come in even closer, we
might see some of the tracks.
That's good.
I see it on my screen,
so I think you can see.
Just toward us from
the edge of the crater
we can see kind of a V shape.
It's very subtle.
These very thin lines.
And then a line that
goes through it.
So it's sort of like
an upside down A.
And then, it exits
off to the right.
And so Micah, I guess we can
move out in that direction.
But those are the tracks
that Opportunity made.
Oh, Micah is brightening it up.
That's great.
I can see them quite well now.
So those tracks of Opportunity.
And notice those sand dunes.
Beautiful sand dunes down
there in the bottom of Victoria
crater.
And again, the
dark sand of Mars--
this is-- in some
areas, it's light
because the dust
has been blown away.
And some areas, if it's
light material, and then
some-- in this case, the dust
that's been blowing around
is darker.
We think it's darker
because it's iron rich.
There's a mineral
called olivine,
which contributes to the
dust in the sand on Mars.
And so if you've ever been to
the Black Sand Beach in Hawaii,
that's made from these sort of--
well, basaltic is the
name of it, the mineral.
But from the
volcanoes in Hawaii.
I'll talk a little bit
about that next as well.
But now, we're looking at
the ultimate destination
of Opportunity.
This is a crater so wide
it's about 13, 14 miles wide.
Do you see those hills
in the background?
There's some more
detailed pictures
in the middle of the crater.
But beyond that, we see a hill.
And then, in the right,
we also see hills.
So this crater used to be much
more defined, but erosion--
possibly these lakes
eroded it down.
And Micah, right
down in the middle
at the bottom of the screen is
where Opportunity went first.
It was called Cape York.
And then, they did a lot
of investigation there.
And then, Opportunity
spent a couple
of years exploring, basically,
this edge of a crater.
Now, because craters
come down and they
punch a hole in the surface
making this big round hole,
you can use it as a geologist.
And so these rovers
were designed
to be robot geologists.
And so they carried
a lot of instruments
to look at the
minerals and so forth.
We're looking for the conditions
that may have supported life.
Because we're not
only the water planet,
we're the life planet on Earth.
And yet Mars, seeing
evidence of water, at least
in the past, that Mars seems to
have had water around the time
life started on Earth.
And so it's a very
interesting question
if life had started on Mars.
So Micah is going
to bring us now down
to the final resting
place here in what's
called Perseverance Valley
[INTERPOSING VOICES]
JACKIE FAHERTY: I
think it's going to be
related to where we're going.
We've got a question from Mary
from Holland, Pennsylvania,
which is, what
happens to the rovers
when they reach the
end of their lives?
You were about to
say a resting place.
CARTER EMMART: Yes.
So the rover basically
uses its batteries.
And then it's charged
up by its power source.
In the case of
Curiosity, I mentioned,
it has a plutonium battery.
Mars is cold.
Plutonium, as it
decays, is warm.
And so if you run a
thermocouple in between
it generates this
battery, essentially.
But with solar
power, what you have
to do is every day
when the sun comes up
you charge your battery
and then run off of that.
And so it was amazing that
these rovers designed for three
months got this much use.
Now, Micah, bring us over
the ridge here please.
Just in this little
break, this is looking out
across Perseverance Valley,
or this little part.
And Opportunity was hopefully
going to explore down--
not at the bottom of
the crater, but it
was going to run along the
bottom part of this hill.
And that you can
see what geologists
call a bench of rockets.
Think of like a bench that you
would sit on or a stair step.
And you see another
little crater
down there, and so forth.
Micah is actually piloting us
down so close in this image,
as I mentioned,
the smallest thing
you can see in these
images from the high rise
camera on our Mars
Reconnaissance Orbiter
is something like the
size of a soccer ball.
So this will relate now
to a picture we have,
which is the last
panorama of that
was created by Opportunity.
And so Micah is lining up.
This is really nice.
And then, we'll ask Micah
to turn on the picture.
You can see sand dunes
in the upper right.
There's a little
parallel things.
Ah, there it is.
Notice how this picture
is kind of funny.
It's made up of many pictures.
And this is nice
to show because it
shows how we map Mars, even
from above with our satellites,
is that we take
many, many pictures
and we put them together.
We stitch them together.
So that creates this view.
And here, we can actually see
the view that Opportunity has.
Now, I don't see
Opportunity in this picture.
So this picture was taken
before Opportunity got here.
But I'm sure several
of you are probably
wondering that question.
Jackie, I don't know if
there are any other questions
relating to here.
JACKIE FAHERTY:
Yeah, we actually
have two good ones right here.
One is more a comment maybe.
Little Neato, who's
seven years old,
is asking should we just
rename Mars the sand planet
because you've talked
so much about sand.
CARTER EMMART: Oh yes,
well it is a desert world
and a former water planet.
So I think now we want to ask a
question more about this water
question.
I think the sand planet
is a good name for Mars.
Because sand is everywhere.
So Micah is going to
turn us around here.
JACKIE FAHERTY: One
more here too, Carter.
Just because we're
turning around.
Because Gus who's five
has a great question.
And that is one about how
expensive the rovers are.
And if schools can help
somehow in making them.
CARTER EMMART: Wow,
well, that's actually--
the answer to that is yes.
I went to the University
of Colorado in Boulder,
and we were one of the first
universities for students
to actually make a satellite.
And students contribute
to space missions.
On the New Horizons
mission to Pluto,
there was a dust collector
that was developed by students.
I think at the University
of Colorado as well.
But they are expensive.
Maybe upwards to about a billion
dollars on a bigger mission.
But as I say, NASA's
been investigating.
In this case, these are cheaper.
These were not a
billion dollars.
I think maybe even
less than half
of that, Opportunity and Spirit.
However, we didn't just get
90 days of investigation.
We got 14 years in the
case of Opportunity.
Spirit didn't last that long.
And Curiosity is operating
over in Gale Crater right now.
And that is-- that
landed in 2012.
So we're rising up above Mars.
Now, Micah, can we
go up over-- we're
going to go over Aires Vallis,
which is to the upper left.
Yeah, we're going to turn.
We're going to see more
of these dried riverbeds.
And so think about
what's going on here.
You have all these
craters come in.
Boom, boom, boom.
And they pulverized the surface.
There are big craters
and small craters.
And so what it does is it--
it pulverizes the surface.
The scientists
call it a regolith.
It's basically a
pulverized surface.
And then, Mars had rain.
We see these flows.
So what happened?
Well, Mars is colder than Earth.
It's farther from the sun.
So it's farther
from the camp fire,
if you want to think
of it that way.
And so the water
would have percolated.
It would have gone
into the ground
and frozen into ice aquifers.
But upwellings or
other craters coming
in just disturbing
the surface actually
could create a
disturbance to that ice.
And in this case,
we see evidence
of giant outflows on Mars.
And we believe
that this happened
after the big cratering
episodes, and after the rain.
So let's fly over this, Micah.
This is nice.
And just off to the
right is where Pathfinder
had landed back in 1997.
And dead ahead is where
the Viking 1 Lander
landed in Chryse Planitia.
But this is Ares Vallis.
And we can really see how
the water scoured this area.
And there's a river--
there's another channel
coming in from the left.
And they're all
running down hill.
And in this case, down
hill is to the upper right
and flows into the Chryse basin.
And remember, I said basin
is like a really big impact.
So we're going to
look at-- we've
seen the evidence of the water,
but where does water come from?
So Micah, let's fly now off to--
oh actually, just
before we do, I
want to show the evidence
that we can see ice
underneath the surface.
Micah has another picture.
I'd love to bring that
up, if we could please.
And Jackie, I don't know if--
I'm sure there are
tons of questions.
JACKIE FAHERTY:
Tons of questions.
And I think we have to
give some shout outs
to some students that
are putting in here.
Our Lady of Peace Lynnbrook
class of 2020 is here.
So welcome in
watching about Mars.
There's a lot of questions
about the ages of things.
And maybe you could comment
on the last time water
was probably flowing on Mars.
CARTER EMMART: And I'd
like to comment on that.
But before I do, I just want
to show this interesting image
of a crater that happened
while the Mars Reconnaissance
Orbiter has been orbiting
since like 2006, I believe.
And so what we're seeing here
is that white area in the middle
is actually ice that's been
exposed by this crater.
So we actually see
the evidence of ice
under the surface in various
ways by various missions.
But I wanted to show this
picture because it actually
shows the ice exposed.
So Jackie, the last time
the water was flowing.
That's a really good question.
And Micah, I think you can turn
off the slide now, I think.
But to answer that question of
when the last time water flowed
on Mars is that we
look at these features,
and we judge them by how many
craters they have or are they
covered with dust and so on.
The analysis and the
best guesses for ages
are based on the cratering
record we actually
see on the moon.
And where the oldest moon rock
is 4 and 1/2 billion years old.
We know that the smooth
areas on the moon
are about 3 billion years old.
We can tell that from these
comparisons is that Mars--
here we have the canyon
over on the left.
But Micah is going to
fly us past the canyon.
We'll fly a little bit
to the right, Micah,
and also notice how we're
getting less craters here.
We're coming up to an area
where the volcanoes are.
But the best analysis
of looking at Mars
and comparing it to
the moon and the Earth
is that the last time
water was flowing
on Mars was around the
time life began on Earth.
And we're talking about three
billion years ago, or even more
about 3, 3 and 1/2
billion years ago.
This area of smooth, less
craters, and then we're
passing over a
small volcano here.
But we're also seeing
another volcano coming up.
It's so high that it's
stuck up in the atmosphere.
So Micah, if we can
climb up a little bit.
We're going to take
you to the biggest
volcano in the solar system.
And of course, that some of
you may already know the name.
It's called Olympus Mons.
And so we're passing over
smaller volcanoes here.
But then coming up
over the horizon,
we're going to start
to see Olympus Mons.
And it's so tall that it sticks
up out of the atmosphere.
So we have to proceed forward.
We need to go forward, Micah.
And also, off to the right.
Yeah, that's fine.
There we go.
We can see it.
Understand.
And so what we're now seeing--
it seems dark on the top
just because it's sticking up
out of the atmosphere.
The atmosphere actually
lightens up what's around it.
This volcano, the largest in
the solar system, Olympus Mons,
is about the size
of New York state.
And up on top, typical of
volcanoes, well, we'll climb up
and we'll look down on it,
is what's called a caldera.
And so a caldera
looks like a crater.
Craters that we've been
seeing all over Mars
are caused by asteroid impact.
And so the moon we see all
these holes on the moon.
We see all these holes on Mars.
And for the most part,
they are craters by--
impact craters
falling in asteroids.
But here, what we see
on top of volcanoes
is a collapse basically
because the lava comes out
and then it stops and then
it collapses up at the top.
That caldera is
about 50 miles wide.
You could take all of New
York, the five burrows,
you could add in a little bit
of Connecticut and New Jersey,
and it would all stick right
there in that called caldera.
You also take the size
of Beijing or Shanghai
or Melbourne, Australia,
or any big city, Berlin.
They're all about-- they're
all roughly the same size.
London, Paris, Cape Town.
So what we're seeing is what's
called a shield volcano.
And it's very much like
the volcanoes in Hawaii,
which actually have this
lava that comes out.
Some volcanoes are
more spiky, and would
be more exciting to climb.
This volcano is very big, but
the slope is very shallow.
And similar to the
volcanoes in Hawaii.
They're called shield
volcanoes because they kind of
look like a big shield
you might hold up,
or a Greek warrior
held up shields.
So it looks like a shield, it's
the size of New York state.
Yes, Jackie.
JACKIE FAHERTY: We have a
very, very curious audience
on the senses of what might
happen around a volcano.
I'm seeing a lot of
questions about smells.
Elaina, for instance,
is asking if there
are any smells on Mars.
If there were, what kinds would
you smell around a volcano?
CARTER EMMART: Well,
that's a good question.
So what comes out of volcanoes
is, of course, they erupt.
And they erupt gases.
They erupt water.
They erupt sulfur.
And if you've ever been
around sulfur dioxide,
that's a smell of rotten eggs.
So volcanoes are smelly.
So this is where we think
the water came from on Mars.
And then, that created
clouds and rain.
We see clouds now on Mars.
They are ice clouds.
Micah, we want to now go
before we lose any more time,
I want to go to
the canyon on Mars.
And I want to talk-- we
will back out to see,
not only this volcano, but a few
volcanoes of this part of Mars.
This part of Mars
is called Tharsis.
Now, the name comes from
names of gods and warriors.
As a god--
Mars is considered a
planet associated with war
because of its red color.
But Tharsis here is a region
that we could see and name
from our telescopes.
But when we got there,
we saw these volcanoes.
And so you can see the
smooth planes, less craters.
And so Mars bulged out.
Had a lot of volcanoes
on this side.
But when it bulged
out, it actually--
because of this bulge, and
we don't exactly know why,
but it created a vast series
of cracks or fractures,
and created this giant canyon.
We're coming in over
Noctis Labyrinthus,
which is the western portion.
This is where the
canyon breaks up
into a series of
labyrinth canyons.
So it's called the
labyrinth of night.
And it breaks up and
forms this giant crack
we call Valles Marineris.
And the giant canyon on Mars.
And so it formed from,
again, Mars bulging up.
It's kind of like when you cook
bread or a cookie in the oven.
It rises, but it also in it's
rising, it gets crispy on top.
And then, it stretches and
breaks apart while it's still
gooey on the inside.
Well, we'll talk a little
bit about that here.
Micah is going to come in a
little closer on the canyon.
And so what's happening
here in the canyon,
we actually call it a rift
valley because it's spreading.
So it's rifting.
It's moving apart.
And if you've ever been to
the Grand Canyon in Arizona
or seen pictures of it, these
two little tributary valleys--
and Micah will bring us down a
little closer to it, I think.
They're the size of the
Grand Canyon in Arizona.
But this canyon is
about five times deeper.
These canyon walls are
about 20,000 to 30,000 feet.
In fact, the deepest
part of this canyon
is higher than our biggest
mountain on Earth, which is Mt.
Everest.
I forgot to tell you that
the Olympus Mons volcano is
three times the height of Mt.
Everest.
And so we're really
talking about here on Mars,
once again, it's half
the size of Earth,
but has geology that makes Earth
just look small by comparison.
JACKIE FAHERTY:
Carter, quick question
in here from Luciana from Chile.
And it's a question
about where--
she's trying to get scale here
in terms of how far away we are
from those rover sites,
and whether you'd ever want
to send a rover into this area.
CARTER EMMART: Well, that's
a really good question.
We're about to come into some
very spectacular scenery.
And this is where you
just want to send a rover.
And in fact, Micah's just
added in even more detail here.
We're going to come up and see
some real beautiful detailed
images.
And so these series of
cracks make up the canyon.
And then, the canyon widens
out through faulting of these--
so it's still growing.
We think this canyon is
actually still growing.
But as we saw with where
Opportunity landed, to be safe,
we want to land in
a really flat area.
So there's a tension
between, hey, I
want to go to where
it's really exciting.
And where it's safer
to land a rover.
Our new rover that
hopefully will
be launched on the Mars 2020
mission is called Perseverance.
And notice it's
Perseverance Valley where
Opportunity finally has
its final resting place.
That rover has been
named for, in part,
by the final resting
place of Opportunity
in Perseverance Valley.
As we come down into the
canyon, the canyon opened up.
And then, layers-- we
see evidence of layers.
And Micah's coming down into
some very beautiful terrain,
but finely layered.
Now, in the beginning,
I showed you
where there was dried riverbeds.
So we saw basically rock--
craters have been made.
And then they were
modified by water flow.
In this case, what we
see are these channels.
We see we see all sorts
of interesting stuff.
But as Micah gets close, we're
going to see these layers.
It almost looks like wood grain.
And these layers--
and they say, well,
wait a minute, OK,
the canyon formed,
but where did these
layers come from?
They're lighter
toned, and we can also
tell from spectroscopy
from orbit
that they are made of sulfates.
Now, the sulfur from
the volcano, we believe,
combined in the chemistry
in the atmosphere
and created sulfates.
And that the clouds
of sulfates going up,
and also the seasonality of
Mars may have laid these down
annually year after year.
We actually see layered
deposits up at the poles now,
where we have frozen water
and frozen carbon dioxide.
But these layers were laid
down after the canyon opened.
But then they were
sculpted by the wind.
And so as evidence
of that, we see
the wind has blown away and as
over billions of years now have
carved these features.
You might wonder how
big these hills are.
These hills are about the size
of a tall building in a city.
Whereas, that background,
the edge of the canyon--
Micah, can we tip up just
a little bit to see it?
Is that that's
about 20,000 feet.
And also Micah has brought
us down to some sand
dunes that are right down in the
lower center of view right now.
And so what we see
is the sand that's
been blown around in the
wind carving these features.
Well, where has that sand gone?
It's gone into
little sand dunes.
And so that's what we see
those sand dunes down there.
So now, we see this
fantastic area.
It's called Western
Candor Chasma.
So Candor is one of the canyons
that makes up Valles Marineris.
So we're inside the
Valles Marineris
inside one of its canyons,
and of tremendous scale.
And so if we actually
look from above,
we can see how these knobs
or these little hills
are somewhat organized
almost like weathervanes
because the prevailing
wind directions.
And those winds are coming
off the tops of the canyon.
So the wind goes up and it
cools, and then it sinks.
And so it's coming
down in this area.
Probably had very high winds
to carve these features.
And you can kind of see--
these hills are called yardangs.
It's a geologist's term
for these long hills
carved by wind.
And when they're are a
bunch of yardangs together,
they call them fleets,
just like fleets of a ship.
It's like the bottom of a
boat turned upside down.
So that's what they look like.
They're carved.
JACKIE FAHERTY: Carter,
we're short on time now.
But we've got a very young
audience in the chat,
I can tell.
And they're curious on
one thing about you,
and if you would go to Mars.
Because so many
of them have never
seen Mars like
this, and now feel
like they might want to go.
[INTERPOSING VOICES]
CARTER EMMART: Oh, I
love that question.
I was eight years old when
Neil Armstrong and Buzz
Aldrin landed on the moon.
I later got to know
Buzz Aldrin quite well.
I'm an artist, so I drew
a lot of pictures for him.
I wanted to go to Mars.
And we held a conference at
the University of Colorado
when I was a student.
I would love to go to Mars.
But it's not for
me, I'm too old.
It's for your generation.
And your generation
will probably
go because Mars now
is much more in reach
than it has been in the past.
And so I think it's exciting
for your generation.
But this visualization
with OpenSpace software.
You can download this.
Our team whose on the
chat, if you're interested,
you can go to
openspaceproject.com,
that's our website.
And you can download
the software,
and you can do this at home.
At the Hayden Planetarium, when
it's operational, we do this.
And this is the closest to being
on Mars that I'll ever get,
and that probably
many of us will get.
But the data that is sent back
and turning it into pictures,
all of this is real.
We have not
exaggerated any scale.
These are maps.
This is what NASA does.
It sends these pictures back.
And our job at the museum
is to take all that stuff
and put it into something
that we can share with you
and give to you as a tool
so that you can explore.
And hopefully, this
will inspire some of you
to actually go to
Mars in the future.
And that's, I think,
that's a pretty big deal.
So I really want to thank
you all for joining us today.
JACKIE FAHERTY: We'll just
take one last question on this.
Because I also think
that I agree, that
CARTER EMMART: Oh
there's the polar cap.
We can see it down
there, Jackie.
I just want to point it out.
JACKIE FAHERTY: I
don't blame you.
When we get-- when I see
things in OpenSpace like this,
it actually made me feel
at peace with the idea
that I wouldn't
be going to Mars.
And that I didn't really
want to go anymore
because I could see it so well.
So the last question
from Rayna, which
is, how long would it
actually take a human
to get from the Earth to Mars?
CARTER EMMART:
Well, so there are
different types of missions.
But the basic mission is that
you spend about six to eight
months getting to Mars on what's
called a home and transfer
orbit.
You come up and you lead
Mars and you meet up with it.
And that's how we send
all our robots there.
But then, you'd probably
stay on Mars for a year.
And then, you return.
And then return--
you say, OK, now I've
been in space for
a year and a half.
Well, the return after
a year, the planets
are aligned such that
it's a longer return.
And it takes about
a year and a half
to return using
a Venus swing by.
So a journey to Mars is about
1,000 days, about three years.
So it's a long journey.
And that people
are going to have
to really prepare for that.
I have a friend
who sailed around
the world in three
years, and was
isolated and
completely self-reliant
like a true Mars mission.
And so it's going to really
take tough individuals that
can really be friendly
with one another,
and explore an entire new world.
JACKIE FAHERTY: I know we've had
so many students in the chat.
So this is very inspirational
for them to think about,
and to keep your
dreams moving forward
if you want to explore
space like this.
As a reminder to folks that--
there's actually a quiz you
can take at the end of this
that is a fun quiz to take.
And a survey that we're
asking you to fill out
if you've been watching so
that we can get some feedback
on this kind of program.
We'd like to bring
you more of them.
So thank you for watching.
Carter, I'm sure you can have
the last word on our goodbyes.
CARTER EMMART: Well, I
just want to thank you all.
Because you all, who are young,
and this is your project.
This is a project of a lifetime.
It's a project of an entire
species of our planet, really.
It's from space
it's obvious, there
are no national boundaries.
And this is a project
for all of us, hopefully,
to go together to Mars.
Thanks a lot.
Thanks for joining us.
