GEORGE DILLER: Mars... Our planetary neighbor has long intrigued us
and invited speculation about whether life exists there. Recent successful
missions like NASA’s Mars rovers have yielded increasing knowledge about
the red planet's geology and history. Now, a new space explorer is waiting in
the wings and ready to take center stage: the Mars lander called Phoenix.
Set for launch aboard a Delta II rocket, Phoenix will dig through the Martian
soil and ice in the arctic region using a robotic arm. Phoenix will use its
onboard scientific instruments to analyze the samples it retrieves.
By using the Deep Space Network tracking stations, scientists on Earth will be able to
communicate with the spacecraft. They hope to learn more about existing
water on the planet, as well as search for any signs that some form of life could exist there.
The Phoenix mission should take us one step closer to the
goal of someday conducting human exploration of Mars. Join us now at the
Kennedy Space Center in Florida as we take an in-depth look at preparations
for the launch, and learn about the science of our next mission to Mars, Phoenix.
Music.
TIFFANY NAIL: Welcome to the Phoenix webcast. I'm your host,
Tiffany Nail. Today, we're going to take you out of the studio and into the field to
show you where all the action takes place in the weeks leading up to liftoff.
You'll see how the rocket takes shape at the launch pad as the spacecraft
undergoes its final tests just a few miles away. So let's get started. Our
mission manager, Ron Mueller, is going to join me at the clean room where
the Phoenix lander is being prepared for launch. But first, here's Ron to tell
us a little more about the spacecraft.
RON MUELLER: The last stop on Earth for the Phoenix spacecraft is
NASA's Kennedy Space Center in Florida. Built in Colorado by Lockheed
Martin Space Systems, Phoenix arrived at the space center's Shuttle Landing
Facility aboard a U.S. Air Force C-17. From there, it was transported to a
clean room at the Payload Hazardous Servicing Facility for preflight testing.
The final checkouts include spin-balance testing with and without fuel,
testing the heat shield separation, verifying the launch and cruise stage
systems, and conducting solar array deployment and lighting tests.
Workers loaded flight software and performed compatibility testing with the
Deep Space Network. The parachute that will slow the spacecraft's descent
through the thin Martian atmosphere was installed, and the electrical power
system was put through a final performance test. The landing radar was
integrated and the entry, descent and landing system verified. Following all
the tests, the spacecraft can then be installed on the third stage before
moving to the launch pad in a transportation canister.
With the third stage attached to the
Delta II rocket and covered with a protective fairing,
Phoenix will await liftoff on its exciting journey to Mars.
NAIL: I'm here now in the Payload Hazardous Servicing Facility with Ron Mueller.
Thanks for joining me, Ron.
MUELLER: Good to be here, Tiffany.
NAIL: Ron, could you explain to us your role as mission manager for Phoenix?
MUELLER: Sure. As mission manager, I work with the spacecraft team and
the launch vehicle team here at Kennedy Space Center to ensure that the
spacecraft is designed and tested to withstand the environment during launch
and prepare all the steps along the way so that everything is readied for launch.
NAIL: Ron, one of our viewers, Justin from Flint, asked, "How do we get
the lander out to the launch pad and up on top of the rocket?"
MUELLER: The first step in moving the spacecraft out to the launch pad is
to bring the third stage of the launch vehicle here to the PHSF. The
spacecraft will be mounted to that third stage.
That stack will be encapsulated and then transported out to the launch pad,
where the rest ofthe vehicle awaits.
NAIL: Jessica from Denver wanted to know what protects Phoenix from
getting damaged during the launch.
MUELLER: To protect the spacecraft from damage during launch, we first
do a lot of analysis and testing to ensure that the spacecraft is designed to
meet that environment. Additionally, there's a fairing on the launch vehicle
that helps protect the spacecraft during the launch phase.
NAIL: Ron, thanks for joining me outside the clean room.
MUELLER: You're welcome.
NAIL: While final preparations are under way here on the spacecraft, the
rocket that will carry it is being readied just a few miles away at Launch Pad
17-A. Before Launch Manager Chuck Dovale joins me at the pad, here's our
deputy chief engineer, Dave Sollberger, to tell us how the rocket is prepared for launch.
DAVE SOLLBERGER: The launch vehicle that will carry the Phoenix
spacecraft on the first leg of its journey to Mars is the Delta II rocket.
Deltas have been carrying NASA spacecraft aloft since the 1960s, and today's Delta
II has a long history of successful launches. Unlike the space shuttle, which
is moved to the launch pad fully assembled, the Delta II is erected on the pad
in stages. In a hangar at Cape Canaveral Air Force Station, workers prepare
and test the first and second stages of the rocket before moving them to the
launch pad. Once the first stage is hoisted into place on the pad, the nine
solid rocket boosters that will help propel the Delta II are attached. Workers
then raise the second stage atop the first, as the powerful launch vehicle
takes shape. In the final days before launch, the spacecraft is attached to the
upper-stage booster before moving to the launch pad in a transport canister.
Once the spacecraft is mounted atop the rocket and covered with its
protective fairing, the Delta II awaits its thunderous liftoff and the beginning
of another exciting mission to Mars.
NAIL: I'm here at Launch Pad-17A with Phoenix Launch Manager Chuck
Dovale. Chuck, thanks for joining us.
CHUCK DOVALE: Thanks, Tiffany. It's a pleasure to be here.
NAIL: Chuck, Can you tell us what work is going on behind us here?
DOVALE: We're to the point of testing the launch vehicle on the pad. We've
got the first and second stage mated and we'll run through a series of
electrical and mechanical checks before we do a simulated flight.
We'll load the first stage with liquid oxygen, make sure that the tank system is sound
and willing to take cryogenic temperatures. It's all in preparation for the
spacecraft and its third stage to roll out. Once we roll them out and mate
them to the launch vehicle, we'll perform an integrated test, make sure that
the launch vehicle and the spacecraft are working well together,
and that's all in preparation for countdown.
NAIL: Chuck, I have two questions from our viewers. Timothy from
Springfield would like to know, "Why does a Delta II rocket need so many boosters?"
DOVALE: It's all about performance -- how much does the spacecraft weigh
and where's it going? So in the case of Phoenix, it's a fairly heavy spacecraft
and it's going to Mars. So we needed a vehicle that would be able to lift off
the ground with Phoenix and take it through Earth's gravitational
pull and head on to Mars.
NAIL: Kevin from Bowling Green would like to know what makes a Delta
II rocket the right one to carry the Phoenix spacecraft.
DOVALE: We look at three things when we're evaluating a mission.
We look at cost effectiveness. We look at past performance and capability of the
launch vehicle. Can it lift the mass that we have and take it to the proper
orbit? In the case of Phoenix, we looked at that and this particular
configuration of the Delta II was a perfect match for Phoenix.
NAIL: Well, thanks, Chuck, for joining us and good luck on launch day.
DOVALE: Thanks, Tiffany.
NAIL: Phoenix principal investigator Peter Smith from the University of
Arizona has graciously agreed to answer some additional viewer
Questions about the science of the mission. Here's Peter.
PETER SMITH: My name is Peter Smith. I'm the principal investigator of
the next mission to Mars called the Phoenix mission. Phoenix is going to
Mars to an arctic region to investigate a discovery made in 2002 by the
Odyssey spacecraft that the arctic region has ice near the surface,
surrounding the actual exposed polar cap. In other words, it's sort of a
permafrost region on Mars that was only recently discovered and whose
properties are totally unknown. So Phoenix is a voyage of exploration and
discovery. Putting the spacecraft down on one of the colder parts of Mars is
really something that has stressed our engineering team, and so we've had to
come up with a well-insulated container to hold our electronics, which only
work down to certain temperatures, and then we put in heaters to keep those
electronics above that temperature at all times. Now of course, this takes
some of our solar power, and as winter comes to the spacecraft and the sun
sets, it gets extremely cold -- so cold that it actually freezes out the carbon
dioxide atmosphere into dry ice. And you get a layer of dry ice that actually
encases the spacecraft, and no solar energy for the heaters. And so, at that
point, the electronics would be stressed past the point where they're
guaranteed to work and it'd be a miracle if they survive through that winter,
but we may try and listen in the spring and summer of the next year just to
see if it did. I suspect it won't. The robot arm is very strong. If, if you were
to brace your legs and hold on to that arm and try and stop it from moving, it
would drag you. So it's a strong arm. It may actually even move the
spacecraft. So we feel very confident we can get through even very hard-
packed soils. Now when we get to the very cold ice that's almost a pure ice,
it's the hardness almost of granite. And so we've put a power tool on the end
of the arm that actually acts as a rasp, and it spins and it throws pieces of ice
chips inside of the back of our scoop, and we can deliver those to our
instruments. So we are sure that we'll get a sample of even the hardest
materials. NASA developed airbags as part of the Pathfinder mission and
decided to use them again for the Mars rovers. However, the spacecraft we
have inherited was designed before Pathfinder was successful (its propulsion
system was designed). And so we've gone back to the, the landing system of
the Vikings, the two Vikings, which is using thrusters, and we feel that we're
very safe using thrusters. And in fact, for us to use airbags would have to
reduce the mass of our spacecraft and that would be, mean less science and
less capability, so we're very happy with thrusters. The closest we've ever
been to the polar regions with a lander, a successful lander, was Viking II,
and it landed about 45 degrees north latitude. On the Earth, that would be
somewhere near Chicago, I think, and very far from northern Canada or
northern Greenland, which is the latitudes we're going to (using an Earth
analog). Now there was an attempt to get to the polar regions in 1999 with
Mars Polar Lander; unfortunately, it failed to land safely. And we are
actually reusing some of the instruments that were on that mission and,
hopefully, we will have success this time, and that's really the reason for the
name "Phoenix." Phoenix is a long-lived bird that dies in flames and is
reborn from its ashes, so it's a symbol of rebirth.
NAIL: I hope you enjoyed the program. I want to thank our guests for giving
us this inside look at what goes into a successful launch and mission. Join us
live for the Phoenix liftoff on NASA TV or on your computer at
nasa.gov/Phoenix. Thanks for joining us. I'm Tiffany Nail.