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ZL2VAL > ROVERS 06.08.04 12:51l 108 Lines 5762 Bytes #999 (0) @ WW
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Subj: Press release, August 5th
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From: ZL2VAL@ZL2AB.#46.NZL.OC
To : ROVERS@WW
NEWS RELEASE: 2004-194
August 05, 2004
Rocks Tell Stories in Reports of Spirit's First 90 Martian Days
Scientific findings from the NASA rover Spirit's first three months on
Mars will be published Friday, marking the start of a flood of
peer-reviewed discoveries in scientific journals from the continuing
two-rover adventure.
Researchers using Spirit's toolkit of geological instruments from early
January into April read the record from rocks and soils in the rover's
landing area and found a history of volcanic blanketing, impact
cratering, wind effects and possible past episodes of scant underground
liquid water. Evidence for the water comes from mineral alteration in
the veins, inclusions and coatings of some rocks. Eleven reports with
120 collaborating authors from around the world lay out details in the
Aug. 6 issue of the journal Science.
"This is the first batch," said Dr. Steve Squyres of Cornell University,
Ithaca, N.Y., principal investigator for the science payload on both
Mars Exploration Rovers. "You'll be seeing a lot more publications in
months ahead and, no doubt, for many years to come based on information
from Spirit and Opportunity. These machines just keep going and going,
so the science just keeps coming and coming." Dr. Jim Garvin, NASA's
Chief Scientist for Mars added, "This is the basis for beginning the
remarkable scientific legacy of the rovers that will not only rewrite
our textbooks about Mars, but also pave the way for human exploration."
The rovers completed three-month primary missions in April, then began
bonus exploration in extended science missions. "Spirit and Opportunity
have really done yeoman's work, still operating after more than twice as
long as their original assignments. We don't know how much longer
they'll keep working, but while they do we promise to keep them busy,"
said Jim Erickson, project manager at NASA's Jet Propulsion Laboratory,
Pasadena, Calif.
Both rovers were equipped and targeted to collect evidence about past
environmental history, especially any history of liquid water, since
life as we know it depends on water. Spirit is exploring inside Gusev
Crater, an ancient Connecticut-sized impact basin that was selected as a
landing site because it may have once held a giant lake fed by flows of
water though a large valley that empties into the crater.
The new reports state that, in its first three months, Spirit found no
evidence of lake-related (lacustrine) deposits. "Any lacustrine
sediments that may exist at this location within Gusev apparently have
been buried by lavas that have undergone subsequent impact disruption,"
says the leadoff paper by Squyres and 49 other rover science team
members. Spirit has subsequently driven to a different location --
nearby hills over 3 kilometers (2 miles) away -- to continue exploring.
Dr. John Grant of the National Air and Space Museum, Washington, and
co-authors report that the rocks on the plain that Spirit explored
during its primary mission increased about fivefold in maximum size as
the rover got closer to an old 210-meter (690-foot-wide) impact crater.
The impact that excavated the crater brought volcanic rocks to the
surface from as deep as 10 meters (33 feet). Several papers give
evidence that rocks in the area are a volcanic type called basalt and
bear the mineral olivine. These include reports by Cornell's Dr. Jim
Bell with collaborators using Spirit's panoramic camera and by Dr. Dick
Morris of NASA Johnson Space Center, Houston, with collaborators using
the Mössbauer spectrometer. Dr. Hap McSween of the University of
Tennessee, Knoxville, and co-authors state, "These basalts extend the
known range of rock compositions comprising the martian crust."
Dr. Ken Herkenhoff of Flagstaff, Ariz., offices of the U.S. Geological
Survey and other scientists using Spirit's microscopic imager offer
findings that rocks cut into by the rover's rock abrasion tool have
coatings and bright veins apparently from mineral alteration after the
rocks formed. Dr. Ralf Gellert of Max-Planck-Insitut-fur-Chemie in
Mainz, Germany, and other users of Spirit's alpha-particle X-ray
spectrometer report that bromine in the veins suggests the alteration
resulted from exposure to water. Dr. Phil Christensen of Arizona State
University, Tempe, and collaborators using Spirit's miniature thermal
emission spectrometer say the rock's coatings are consistent with
exposure to moisture while buried. Dr. Ray Arvidson of Washington
University, St. Louis, and co-authors describe cohesive texture in soils
and rock coatings, which they suggest could result from brief moist
periods in the past.
Magnet experiments indicate almost all sampled dust particles in Mars'
atmosphere contain magnetic minerals, according to a paper by Dr. Preben
Bertelsen of the Niels Bohr Institute, Copenhagen, Denmark, and others.
Dr. Ron Greeley of Arizona State University and co-authors found that
winds from the northwest grooved some rock surfaces and shaped sand
ripples in the past. They report that the way rock dust accumulates
during grinding by Spirit's rock abrasion tool shows that wind still
comes from the same direction.
JPL, a division of the California Institute of Technology in Pasadena,
manages the Mars Exploration Rover project for NASA's Science Mission
Directorate, Washington. Images and additional information about the
project are available from JPL at http://marsrovers.jpl.nasa.gov
and from Cornell University, Ithaca, N.Y., at http://athena.cornell.edu
73 - Alan, ZL2VAL @ ZL2AB
Message timed: 23:25 on 2004-Aug-06
Wackiest Warning Labels Ever
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* A bathroom heater says: "This product is not to be used in bathrooms."
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