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Narrator: A journey to the north pole—of Mars.
I'm Jane Platt with a podcast from JPL – NASA's Jet Propulsion
Laboratory in Pasadena, California.
A new NASA spacecraft is all dressed up – with a really
cool place to go—literally. Phoenix Mars Lander will
zoom through space and land the middle of next year in the far
north part of Mars, the polar region. Joining us is Phoenix
Project Scientist Leslie Tamppari of JPL. Welcome, Leslie.
Tamppari: Thank you..
Narrator: Well, we already have four NASA spacecraft at
Mars, including the two very long-lived rovers, Spirit and Opportunity.
And the European Space Agency has an orbiter as well. So
what is Phoenix going to add to this mix, to the fleet?
Tamppari: Phoenix is going to an entirely new region that
we’ve never been to before. We’re going to the north
polar region between 65 and 72 degrees north. And we’ll
be able to be in the environment during northern summer when the
water icecap is completely exposed and water is coming off the
cap, and it’s a great place to study the water cycle on
Mars. It's also a place where we have surface ice that was
discovered by the Odyssey spacecraft, and we’ll sample that
ice and be able to tell something about the habitability of the
Narrator: Again its part of the theme of following the
water on Mars, where it might have been, where it could be now
and where it might be in the future. Just a really brief, thumbnail
recap of why we’re so interested in water on Mars.
Tamppari: Water is a big mystery on Mars. We think
that there was vast floods of water very early in Mars’
history, but today we don’t see evidence for floods like
that, that might happen. So we want to understand the current
climate very well so that we can understand what the past climate
might have been like. And of course water is important for
the life, so understanding where the water is and how it's changed
on Mars over its history is very important for understanding if
life ever could have arisen on Mars.
Narrator: And this particular region in the far north part
of Mars enables you to answer different questions than were possible
in the other areas, for example, where Spirit and Opportunity
Tamppari: Yes, Spirit and Opportunity are looking for evidence
of ancient water, whereas we’re looking at the current water.
We’re looking in an environment where in the last 50,000
to 100,000 years, the environment has changed due to the tilt
of the planet changing over that time, and so there might have
been times when liquid water could have been standing on the surface
for a period of time that might have been conducive to life.
So it’s very interesting from that standpoint.
Narrator: So Phoenix will carry seven science instruments.
Can you explain to us what they will be able to do?
Tamppari: Yes, we have instruments that will be able to
gather samples from the surface and analyze those samples onboard
the spacecraft. And then we have a very rich weather station
that will enable us to understand the local weather in our landing
environment. And we have a series of cameras that will allow
us to take images from before we land the spacecraft, and view
our scene before we land, all the way down to measuring a particle
that might be as small as one one-hundredth of a hair width.
Narrator: And this particular mission to Mars is not landing
with airbags as Spirit and Opportunity did and as Mars Pathfinder
did in 1997.
Tamppari:Yes, we have a power descent landing system, so
we’re going to land on legs, and we have engines that will
help slow us down. So basically when we come into the atmosphere,
it’s very similar to all of the previous spacecraft.
We have a heat shield that protects us until we get lower in the
atmosphere, we have a parachute that deploys. All of our
previous spacecraft have used that. So it’s then in
that final one kilometer or so when we have a different mechanism
and that’s when we'll have the heat shield come off, the
legs will deploy and the engines will start and slow us down to
a nice, soft landing.
Narrator: Actually getting to and landing on Mars is very
challenging, and it’s always a real nail-biting experience.
Tamppari: We put a lot of effort into the entry, descent
and landing, that’s about six minutes from the top of the
atmosphere to the landing. And we have a whole team of people
working just specifically on that. So we have not only a lot of
effort and a lot of talented engineering going into that, but
we have a lot of reviews that help challenge us and make sure
that we’ve thought of all possible things that can go wrong.
However, landing on Mars is sometimes difficult and we could get
unlucky, there are things we can’t control. For example,
the winds, we try our best to predict what they might be like
and bound them, but we could get unlucky. In addition, we
have picked a place that we think is very safe with respect to
rocks, but still we might get unlucky and land on the one spot
where there’s a big rock. So we hope not and we’ve
definitely tried to prevent against that to the extent possible.
But it is still a risk to land on Mars.
Narrator: But the rewards are great, and if all goes well,
after Phoenix what will you know that we do not know now?
Tamppari: Well, we hope to really understand the polar
weather. We’ve never had a spacecraft successfully
land in either of the polar regions, so Phoenix will be the first
successful lander. And we hope to understand the habitability
of the landing site, whether or not this location is conducive
for life, should life have ever been on Mars.
Narrator: Thank you very much for joining us today.
Tamppari: Thank you.
Narrator:We've been talking with Phoenix Mars Lander project
scientist Leslie Tamppari of JPL. More information on the
mission is online at www.nasa.gov/phoenix
. Thanks for joining us for this podcast from NASA's Jet
› Mars Odyssey