BOULDER,COLORADO -- NASA's Odyssey spacecraft is putting Mars on the chart.
Globalmapping of the distant, dusty, and baffling world is underway, with firstresults from Mars Odyssey helping to sharpen future robotic exploration plans,and may hasten the day when human explorers reach out for the red planet.
Earlylooks by the Mars orbiting craft suggest that high amounts of hydrogen existbelow surface level in the south polar region of the planet. That hydrogen islikely in the form of water ice, scientists speculate.
Ifso, that frozen layer could, quite literally, put life on ice - acryo-preserved abode for Mars biology.
Moreover,water ice found prevalent across Mars means that expeditionary crews of the 21stcentury would find a "user-friendly" world - a planet far easier toexplore in a sustained and more expansive way.
Cautiousoptimism
"We'rejust a week into a charting missionand it looks awfully good," said JamesGarvin, lead scientist for Mars exploration at NASA Headquarters in Washington,D.C.
Thedetection by Mars Odyssey of a "whopping" amount of hydrogen remainsup for interpretation, Garvin stressed. While water ice is a top candidate anda convincing source, cautious optimism rules the day, he said.
"They[the Mars Odyssey scientists] have some work to do," Garvin said."What it means, we don't know yet," he told SPACE.com.
"It'slike running into an iceberg and not seeing the iceberg field behind it,"Garvin said.
Thereis no doubt, Garvin added, that Mars Odyssey will reveal the red planet insurprising ways.
"I'llpredict that Odyssey will have a major impact, scientifically, on our program. It'sa charting mission. It is designed to help us find where we need to go,"Garvin said. "Give us a couple of months. We'll be parading, morespecifically, what Odyssey is telling us."
Double-timingMars
BruceJakosky, a Mars scientist at the University of Colorado here, said thatincoming data from Mars Odyssey in striking.
Jakoskyis a member of the science team on one of Mars Odyssey's key instruments, theThermal Emission Imaging System (THEMIS). That high-tech device works in thethermal infrared and can resolve objects 328-feet (100-meters) across.
THEMISis working double-time. That is, the system not only sheds light on a nighttimeMars using see-in-the-dark infrared technology, it also makes daytimemeasurements.
Daytimemeasurements will be used to help determine the mineralogical makeup of Mars."The goal is to understand the structure of the crust and to locate placeswhere the minerals indicate that liquid water might have resided," Jakoskysaid.
Nighttimereadings by THEMIS are used to determine physical properties of the Marssurface, gleaned from profiling temperatures. That data can help scientistsdiscern the abundance of dust, rocks, and other material, down to small scales.
Theimportance of Mars Odyssey observations to future robotic missions isstraightforward, Jakosky said. "There is interest in water as part of thesearch for life. If you could identify minerals that were deposited in aqueousor hydrothermal environments, for example, these would be prime targets for futureexploration, he said.
Learningmore about Mars' surface properties is critical, Jakosky added, for safelylanding future craft, plotting out traverses by rovers, and determining whatareas of the planet contain certain rocks ideal to sample.
Life on ice
MarsOdyssey's Gamma Ray Spectrometer (GRS) has made the first direct measurementsconfirming that extensive amounts of hydrogen lurk just beneath the surface ofMars, at least at the planet's southern polar region.
"TheGRS detected hydrogen, which is certainly in water ice in the regolith (the topsurface material of Mars). At the abundance levels they see at those latitudes,I don't know what else it could be other than water ice," Jakoskyconcluded.
Odyssey'sruling that loads of water ice is tucked away at the southern polar region isnot unexpected. The belief that there is evidence for water ice in that"burrow" of Mars has been on the upswing for the last 15 years.
"It'sa wonderful, independent confirmationone that we needed," said JackFarmer, an astrobiologist at Arizona State University in Tempe said.
"Froman astrobiology standpoint, it's quite exciting," Farmer said. A jobremaining is to unearth a place on Mars where recent volcanism allowedunderground magma to reach the surface. It's inevitable that this activity drewgroundwater up to the surface, sequestering it into ice, he said.
"Asthe water comes up, it enters the ground ice inventory at the surface. Ifthere's any biology going on down there, or even interesting pre-bioticchemistry, it's very likely to wind up cryo-preserved in the ice," Farmersaid.
Additionally,if quantities of near-surface water ice were spread across Mars' surface, thatresource would bolster human exploration of the planet, Farmer said.
"Thecloser you go to the poles, the more difficult a [human] mission becomes interms of survival," Farmer said.
"Ifyou could find ice deposits near the surface at lower latitudesthat's whereyou'd zero in. That resource could support human missions, not just for thewater but also using it to make propellants and other things. Basically, itcould be mined out of that inventory of ground ice," Farmer said.
Step-by-stepagenda
MarsOdyssey now joins Mars Global Surveyor in making on going and invaluable scansof the planet. The spacecraft duo is busy using their collective surveyingskills to assist in unveiling the true Mars of the past and present.
Howsoon the first footfall on Mars?
"Theimperative to get explorers to Mars, robots or humans, is there, I believe.It's the question of where to turn the gain up, and when to insertpeople," NASA's Garvin said. "Will Odyssey hit scientific home runs?You bet. Could Odyssey hit the home run that just says we've got to go soonerthan later with humans? I don't know," he said.
Ofimmediate need, Garvin said, is picking the top priority touchdown spots fortwin Mars Exploration Rovers, to be hurled toward the red planet next year.
Garvinsaid that Odyssey would also identify what areas are worthy of more intensivestudy from Mars orbit.
NASA'sstep-by-step agenda includes a 2005 Mars Reconnaissance Orbiter, fully gearedwith ultra-powerful sensors. In 2007, the first of a hoped for series of Scoutspacecraft are to explore Mars, applying innovative approaches to delve intothe planet's closely held secrets. Then, in 2009, a nuclear-powered rover is tocarry out a long-lived and detailed program of surface studies.
Mars returnsample: not so fast?
NASAand many Mars scientists want a robotic mission to grab Martian samples andshoot the specimens back to Earth for lab study. But the idea is just that: upfor grabs.
Nowprice-tagged as a billion-dollar-plus effort, lobbing Mars rock and regolith toEarth brings with it a level of sticker shock that the U.S. Congress and thetax payer is likely to balk at, NASA senses. A just chartered planning group isbusy at work whittling away at Mars return sample costs.
Butkeeping Mars samples away from Earth may be a safety message stemming from thenew Odyssey findings.
GilbertLevin, a former Viking Mars experimenter, said the detection of water ice byOdyssey is old but welcomed news.
Levin,now chief executive officer for Spherix Incorporated in Beltsville, Maryland,said data from his Viking experiment in 1976 supports his belief that liquidwater exists on the surface of Mars.
Furthermore,Levin has long held that his Viking gear found microorganisms in the soil ofMars.
Nowover 25 years later, the advice from Odyssey, Levin claims, is not to be toohasty in bringing back samples directly to Earth.
"Fromwhat we have learned since Viking, it is possible that they [microorganisms]could be same, or nearly the same, species that have recently been discoveredthriving on Earth at places where liquid water is at least as scarce as it ison Mars," Levin said in a press statement.
"But,since they could be quite different, I think this will have a profound impacton NASA's plan to bring a sample of Martian soil to Earth. It seems to me thateven a slight risk to our health and environment exceeds any likelybenefit," Levin said.
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