[meteorite-list] Mars Science Laboratory: Next Wheels On Mars

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Wed Jan 5 15:13:00 2005
Message-ID: <200501052012.MAA24589_at_zagami.jpl.nasa.gov>

http://www.space.com/businesstechnology/technology/mars_science_lab_050105.html

Mars Science Laboratory: Next Wheels On Mars
By Leonard David
space.com
05 January 2005

While those unflappable interplanetary twins - Spirit and Opportunity -
continue to trudge across Mars, engineers and scientists are readying
the next robotic rover destined to trail across the distant sands of the
red planet.

The Mars Science Laboratory (MSL) is bigger, heavier, and more powerful
than the machinery now at work on Mars.

As the next robot to go mobile on Mars, building, testing, and then
flying MSL has its challenges. That being said, and while now a solo
mission, there is already talk that MSL may follow in the wheel tracks
of Spirit and Opportunity - that is, doubling up on Mars.

MSL would pick up, pocket and crush rock and soil samples, then dole out
those specimens to on-board test chambers for chemical analysis.

Carrying a set of scientific instruments, MSL's chores include
identifying organic compounds such as proteins, amino acids, and other
acids and bases that attach themselves to carbon backbones - the
essentials for life, at least as we know it. It would also identify
features such as atmospheric gases that may be associated with
biological activity.

Coming together

Set for liftoff in 2009 and touching down on Mars in 2010, MSL builds
upon the legacy of data gleaned by orbiters, landers, and rovers. But
that doesn't make getting hardware safely down on Mars any easier.

"I think we're in excellent shape," said Peter Theisinger, Manager of
the MSL project at NASA's Jet Propulsion Laboratory (JPL) in Pasadena,
California.

"As you would expect, at this point in time, there's more work to do,
more design uncertainties to retire - but we're in good shape," Theisinger
said. "It's coming together very well right now," he told SPACE.com.

Theisinger is drawing upon a unique reservoir of coolness, bolstered by
his former Mars job. He was project manager for the Spirit and
Opportunity Mars Exploration Rover (MER) Project.

About three times heavier than a MER robot, MSL is on the order of 20
percent bigger in terms of wheel base in both directions, and a little
bit taller, Theisinger explained. With an anticipated mobility range of
some 12 miles (20 kilometers), "we expect it to last two Earth years - one
Mars year," he added.

Planetary hang-time

MSL would be the first mission to steer itself toward the martian
surface, autopiloting its way precisely to a desired landing zone. It
would make its way toward a somewhat circular landing ellipse roughly
between 6 miles to 12 miles across (10 kilometers to 20 kilometers).

That's a much smaller piece of real estate to reach than targeted by
Spirit and Opportunity.

More of Mars will be within reach of MSL than previous landers,
including access to higher terrain and a "fantastic majority of the
southern highlands," Theisinger noted. A decision on where the rover
will set down is still to come.

Imagery from the soon-to-be-launched NASA Mars Reconnaissance Orbiter
will contribute to pinpointing prospective landing sites. "The challenge
will be to winnow down the alternatives," Theisinger said.

One of the tougher MSL assignments is getting the six-wheeled rover onto
Mars.

As currently envisioned, a rocket powered "Skycrane" - offering the
ultimate in planetary "hang-time" -- would hover above the landing site
and gently lower the large laboratory to the surface via a lengthy
tether. After performing its aerial acrobatics, the Skycrane would fly
away and plop down at a spot distant from the MSL landing locale.

Test as you fly - fly as you test

Theisinger said the Skycrane idea has undergone review by experts inside
and outside of JPL's gates. Questions regarding the hardware's
controllability - and how best to shakeout this technology -- have been
attacked with vigor, he suggested, but other landing schemes are also
being studied if the Skycrane craters as a workable plan.

To further assure that the Skycrane landing method is the right
approach, money is being spent on facilities to perform touchdown
testing. "We are very much committed to test as you fly," Theisinger
noted, "and fly as you test."

As was the case for Spirit and Opportunity, the entry, decent and
landing of those vehicles could not be fully practiced end-to-end on
Earth. "What we can't test we have to tie things together with
simulations and analyses," Theisinger said.

MSL is intended to be a long duration, wide-access mission to the red
planet. Given that, nuclear power is the energy of need, Theisinger
said. Surviving on Mars over the long haul and the prospect of widening
the range of MSL's tour-of-duty demands nuclear power, he said.

Doubling up on Mars?

The price tag for the MSL project is just under $1.5 billion - that
includes the rover's nuclear power source, as well as the launcher to
hurl the hardware to Mars - either a Delta 4 Heavy or an Atlas 5 rocket.

At present, MSL is a one-of-a-kind robot mission. That could change.
Talk has begun on tossing two of the roving labs Marsward.

"We have provided the program with estimates of what it would take to
fly two. It's up to my management to decide whether the risk/reward
ratio is favorable for doing that," Theisinger said. "There is no
technical or schedule reason why it's not feasible."

A decision on doubling up on Mars with MSL would have to made within the
first half of this year, Theisinger pointed out. "It's a conversation we
have to have with those developing MSL's payload too - what they would
need in order to build two."

Science toolkit

Last month, NASA selected key science gear and associated investigations
for the mobile Mars rover.

Like any good NASA effort, the MSL project vernacular includes a slew of
weird terms, such as Mahli, ChemCam, and SAM, not to forget CheMin. They
are part of the "toolkit" to be hauled to Mars. MSL science instruments
and their respective principal investigators (PIs) are:

    * Mars Science Laboratory Mast Camera
      : Performs multi-spectral, stereo imaging at lengths ranging from
      kilometers to centimeters, and can acquire compressed
      high-definition video at 10 frames per second without the use of
      the rover computer. PI, Michael Malin, Malin Space Science
    * Systems, San Diego, California. ChemCam
      : A laser-induced remote sensing device for chemistry and
      micro-imaging. It ablates surface coatings from materials at
      standoff distances of up to 33-feet (10-meters) and measures
      elemental composition of underlying rocks and soils. PI, Roger
    * Wiens, Los Alamos National Laboratory, Los Alamos, New Mexico. Mahli
      : This Mars HandLens Imager for the Mars Science Laboratory images
      rocks, soil, frost and ice at resolutions 2.4 times better, and
      with a wider field of view, than the Microscopic Imager now
      onboard the dual Mars Exploration Rovers, Spirit and Opportunity.
      PI, Kenneth Edgett, Malin Space Science Systems, San Diego,
    * California. Alpha-Particle-X-ray-Spectrometer
      : Reveals elemental abundance of rocks and soil. It will be
      provided by the Canadian Space Agency. PI, Ralf Gellert,
    * Max-Planck-Institute for Chemistry, Mainz, Germany. CheMin
      : An X-ray Diffraction/X-ray Fluorescence instrument for
      definitive mineralogical analysis. It identifies and quantifies
      all minerals in complex natural samples such as basalts,
      evaporites and soils, one of the principle objectives of the MSL
      mission. PI, David Blake, NASA's Ames Research Center, Moffett
    * Field, California. Radiation Assessment Detector
      : Characterizes the broad spectrum of radiation at the surface of
      Mars, an essential precursor to human exploration of the planet.
      The instrument would be funded by the Exploration Systems Mission
      Directorate at NASA Headquarters. PI, Donald Hassler, Southwest
    * Research Institute, Boulder, Colorado. Mars Descent Imager
      : Produces high-resolution color-video imagery of the descent and
      landing phase, providing geological context information, as well
      as allowing for precise landing-site determination of the rover.
      PI, Michael Malin, Malin Space Science Systems, San Diego,
    * California. SAM
      : This Sample Analysis at Mars features an integrated set of
      devices consisting of a gas chromatograph mass spectrometer and a
      tunable laser spectrometer. It conducts mineral and atmospheric
      analyses, detect a wide range of organic compounds and perform
      stable isotope analyses of organics and noble gases. PI, Paul
      Mahaffy, NASA's Goddard Space Flight Center, Greenbelt, Maryland.

Exploration-centric

MSL is also toting to Mars a pulsed neutron source and detector for
measuring hydrogen -- including water -- provided by the Russian Federal
Space Agency. In addition, the rover is to be equipped with a
meteorological package and an ultraviolet sensor provided by the Spanish
Ministry of Education and Science.

"The MSL team is working diligently to accommodate the breakthrough
payload that was recently selected, clearly the most scientifically
powerful in history, and our first real 'shot' at following the
biogeochemical cycles on another world," said James Garvin, NASA Chief
Scientist at the space agency's headquarters in Washington, D.C.

Garvin told SPACE.com that MSL will carry devices to measure on-the-spot
ionizing radiation. Also, the heavy-duty rover will perform general
meteorology, water content assessments, mineralogy, and image at scales
beyond those that the Mars Exploration Rovers have so effectively
demonstrated, he said.

The MSL payload is very "exploration-centric", Garvin concluded.
Received on Wed 05 Jan 2005 03:12:40 PM PST