[meteorite-list] Spirit Studies Mars at 'Arm's' Length

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 10:32:03 2004
Message-ID: <200401162303.PAA01439_at_zagami.jpl.nasa.gov>

http://space.com/missionlaunches/spirit_arm_040116.html

Spirit Studies Mars at 'Arm's' Length
By Leonard David
space.com
16 January 2004

PASADENA, Calif. -- NASA's Spirit Mars rover, now parked on the surface of
Gusev Crater has deployed its robotic arm for the first time.

The arm is called the "instrument deployment device", or IDD.

Here at the Jet Propulsion Laboratory (JPL), scientists detailed another
milestone in the traveling road show that is the Spirit rover -- using the
fully deployed IDD to scrutinize the martian soil in minute detail.

One of four instruments mounted on the arm -- a Microscopic Imager -- has
taken the highest resolution picture of the martian surface to date.
Throughout Spirit's exploration of Mars, this device serves as a geologist's
hand lens, outputting close up views of select rocks and soils.

The IDD is tucked under the front of the rover while the vehicle is
traveling. The arm extends forward when the rover is in position to inspect
a particular rock or patch of soil.

Instrument-by-instrument check out

Scientists were delighted at how well the Microscopic Imager is operating,
taking extreme close-ups of the soil, showing the shape and size of
particles.

"My personal view is that this is a conglomerate of dust particles on the
surface of Mars," said Ken Herkenhoff, Science Lead for the Microscopic
Imager from the U.S. Geological Survey in looking at first results. What
holds the talcum powder-like particles together remains fodder for more
study, he said.

Jessica Collisson, JPL Flight Director for the rover mission, said the arm
will be used tomorrow to lower Spirit's Mossbauer Spectrometer directly onto
the surface. That instrument is to run for some four hours.

The device is built to determine with high accuracy the composition and
abundance of iron-bearing minerals - a way to decipher what early martian
environmental conditions existed on the planet.

Later, the instrument robot arm is to be rotated, permitting use of the
Alpha Particle X-Ray Spectrometer. That piece of gear will be positioned to
hover over the soil and run for roughly 20 hours, Collisson said,
determining the elements that make up rocks and soils.

Reports on how well the instruments worked, and what has been learned, is to
be detailed Monday in the next press briefing. By that time, scientists and
engineers should have decided on where next Spirit is to rove at Gusev
Crater, and when use of a fourth instrument, a Rock Abrasion Tool, is
planned.

Fresh tracks

Scientists have begun a detailed look at the rover's fresh tracks, created
as Spirit crawled a short distance, away from the stationary lander
hardware.

"The rover is not sinking in much at all," said Rob Sullivan, Science Team
Member for the rover project from Cornell University. Both science and
operational data can be gained from detailed looks at the rover's tracks, he
said.

Sullivan said that during the rover mission at Gusev Crater, Spirit can be
commanded to really attack the soil. Using a wheel of Spirit, the martian
terrain can be excavated. Doing so, a trench can be dug into the soil in
which the robot's instruments can analyze subsurface materials.

"The more we mess up the soil around the rover, the more we learn," Sullivan
said.

Opportunity's trajectory adjustment

As Spirit steps up its scientific duties on the red planet, the robot's
identical twin -- Opportunity -- is screaming toward Mars. A key trajectory
maneuver is set for late this evening, critical for targeting Opportunity to
land eight days from now at Meridiani Planum, on the opposite side of the
planet from where Spirit sits.

Ground controllers are slated to uplink commands to Opportunity between 2:00
p.m. to 5:00 p.m. Pacific Standard Times (PST), with the trajectory maneuver
to start at 5:52 p.m. PST.

Joy Crisp, JPL Project Scientist for the Mars Exploration Rover effort, told
SPACE.com that the maneuver later tonight will last around 9 seconds. That
will tweak Opportunity's trajectory to precisely enter the martian
atmosphere so it streaks toward its pre-selected landing point.

Dust storm activity elsewhere on Mars had impacted the upper atmospheric
regions over Meridiani Planum. But that dust is settling out, Crisp said.
That should mean clear sailing for Opportunity as it plummets to the surface
and makes use of its landing system.
Received on Fri 16 Jan 2004 06:03:24 PM PST