Fire And Ice: Mars Images Reveal Recent Volcanic And Glacial Activity (climate change)

PROVIDENCE, RI — Shifting glaciers and exploding volcanoes aren’t confined to Mars’ distant past, according two new reports in the journal Nature.

Glaciers moved from the poles to the tropics 350,000 to 4 million years ago, depositing massive amounts of ice at the base of mountains and volcanoes in the eastern Hellas region near the planet’s equator, based on a report by a team of scientists analyzing images from the Mars Express mission. Scientists also studied images of glacial remnants on the western side of Olympus Mons, the largest volcano in the solar system. They found additional evidence of recent ice formation and movement on these tropical mountain glaciers, similar to ones on Mount Kilimanjaro in Africa.

In a second report, the international team reveals previously unknown traces of a major eruption of Hecates Tholus less than 350 million years ago. In a depression on the volcano, researchers found glacial deposits estimated to be 5 to 24 million years old.

James Head, professor of geological sciences at Brown University and an author on the Nature papers, said the glacial data suggests recent climate change in Mars’ 4.6-billion-year history. The team also concludes that Mars is in an “interglacial” period. As the planet tilts closer to the sun, ice deposited in lower latitudes will vaporize, changing the face of the Red Planet yet again.

Discovery of the explosive eruption of Hecates Tholus provides more evidence of recent Mars rumblings. In December, members of the same research team revealed that calderas on five major Mars volcanoes were repeatedly active as little as 2 million years ago. The volcanoes, scientists speculated, may even be active today.

“Mars is very dynamic,” said Head, lead author of one of the Nature reports. “We see that the climate change and geological forces that drive evolution on Earth are happening there.”

Head is part of a 33-institution team analyzing images from Mars Express, launched in June 2003 by the European Space Agency. The High Resolution Stereo Camera, or HRSC, on board the orbiter is producing 3-D images of the planet’s surface.

These sharp, panoramic, full-color pictures provided fodder for a third Nature report. In it, the team offers evidence of a frozen body of water, about the size and depth of the North Sea, in southern Elysium.

A plethora of ice and active volcanoes could provide the water and heat needed to sustain basic life forms on Mars. Fresh data from Mars Express – and the announcement that live bacteria were found in a 30,000-year-old chunk of Alaskan ice – is fueling discussion about the possibility of past, even present, life on Mars. In a poll taken at a European Space Agency conference last month, 75 percent of scientists believe bacteria once existed on Mars and 25 percent believe it might still survive there.

Head recently traveled to Antarctica to study glaciers, including bacteria that can withstand the continent’s dry, cold conditions. The average temperature on Mars is estimated to be 67 degrees below freezing. Similar temperatures are clocked in Antarctica’s frigid interior.

“We’re now seeing geological characteristics on Mars that could be related to life,” Head said. “But we’re a long way from knowing that life does indeed exist. The glacial deposits we studied would be accessible for sampling in future space missions. If we had ice to study, we would know a lot more about climate change on Mars and whether life is a possibility there.”

The European Space Agency, the German Aerospace Center and the Freie Universitaet in Berlin built and flew the HRSC and processed data from the camera. The National Aeronautics and Space Administration (NASA) supported Head’s work.

Hydrogen Peroxide Detected in Mars' Atmosphere
University of Hawaii
Monday, March 1, 2004
What impact does this result have for the search for life on Mars? Dr Clancy says "Hydrogen peroxide is actually used as an antiseptic here on Earth, and so it would tend to retard any biological activity on the surface on Mars. For this reason, as well as the ultraviolet radiation and lack of water, bacteria-like organisms are not expected to be viable on the surface. Most arguments for finding life on Mars now center on subsurface regions."
Studies Cast Doubt on Idea of Life on Mars
by Alicia Chang
12/22/05
...the layered rock outcrops probed by NASA's robot rover Opportunity and interpreted as signs of ancient water could have been left by explosive volcanic ash or a meteorite impact eons ago. That would suggest a far more violent and dry history than proposed by the scientists operating Opportunity and its twin rover, Spirit... The new scenarios, published in Thursday's journal Nature, paint a rather pessimistic view of whether the ancient Martian environment could have supported life... The sediment deposits appear to have formed from volcanic ash that reacted with small traces of acidic water and sulfur dioxide gas, said geochemist Thomas McCollom of the University of Colorado at Boulder... In a second paper, geologist Paul Knauth of Arizona State University proposed another alternative. The rock patterns studied by Opportunity suggest the deposits were produced by a sudden surge of rock fragments, salts and sulfides from a meteorite impact, Knauth said.
Water Could Stay Liquid on Mars
by Bjorn Carey
11/15/05
The elusive quarry has remained hidden, possibly because it may not exist for more than a fleeting second. Due to Mars' low temperatures and extremely low atmospheric pressure – less than a hundredth that of the Earth– pure water evaporates from ice to gas so quickly that it skips the liquid phase.
Orbiter's Long Life Helps Scientists Track Changes on Mars
NASA JPL
9/21/2005
Boulders tumbling down a Martian slope left tracks that weren't there two years ago. New impact craters formed since the 1970s suggest changes to age-estimating models. And for three Mars summers in a row, deposits of frozen carbon dioxide near Mars' south pole have shrunk from the previous year's size, suggesting a climate change in progress... Two gullies appear in an April 2005 image of a sand-dune slope where they did not exist in July 2002. The Mars Orbiter Camera team has found many sites on Mars with fresh-looking gullies, and checked back at more than 100 gullied sites for possible changes between imaging dates, but this is the first such find. Some gullies, on slopes of large sand dunes, might have formed when frozen carbon dioxide, trapped by windblown sand during winter, vaporized rapidly in spring, releasing gas that made the sand flow as a gully-carving fluid. At another site, more than a dozen boulders left tracks when they rolled down a hill sometime between the taking of images in November 2003 and December 2004. It is possible that they were set in motion by strong wind or by a "marsquake," Malin said... Studies suggest new impact craters might appear at only about one-fifth the pace assumed previously, Malin said. That pace is important because crater counts are used to estimate the ages of Mars surfaces.
Ice lake found on the Red Planet
BBC News
29 July 2005
A giant patch of frozen water has been pictured nestled within an unnamed impact crater on Mars... The highly visible ice lake is sitting in a crater which is 35 km (23 miles) wide, with a maximum depth of about two km (1.2 miles). Scientists believe the water-ice is present all year round because the temperature and pressure are not sufficient to allow it to change states. Researchers studying the images are sure it is not frozen carbon dioxide (CO2), because CO2 ice had already disappeared from the north polar cap at the time the image was taken. The team has also been able to detect faint traces of water-ice along the rim of the crater and on the crater walls.
Ice Lake Found on Mars
space.com
29 July 2005
The European Space Agency’s (ESA) Mars Express has snapped an image of a modest ice lake on the Red Planet. The frozen patch of water ice is tucked away in an unnamed impact crater. The feature is located on Vastitas Borealis, a broad plain that covers much of the far northern latitudes. The crater is 22 miles (35 kilometers) wide and has a maximum depth of roughly 1.2 miles (2 kilometers) beneath the crater rim. The ice patch is present all year round, as the temperature and pressure are not high enough to allow the frozen water to escape into the atmosphere.
Water Ice In Crater At Martian North Pole
European Space Agency
July 28, 2005
The HRSC on ESA's Mars Express obtained this perspective view on 2 February 2005 during orbit 1343 with a ground resolution of approximately 15 metres per pixel. It shows an unnamed impact crater located on Vastitas Borealis, a broad plain that covers much of Mars's far northern latitudes, at approximately 70.5° North and 103° East. The crater is 35 kilometres wide and has a maximum depth of approximately 2 kilometres beneath the crater rim. The circular patch of bright material located at the centre of the crater is residual water ice.
Images reveal 'sea of ice' near Mars' equator
Associated Press
Feb 26, 2005
The water is believed to have originated beneath the surface of Mars, near a series of fractures known as the Cerberus Fossae, where it gushed forth in a catastrophic flood after being warmed by the planet's core. It collected in a vast area more than 800 kilometres long and wide, and 15 metres deep. [or, released by a major impact, or carried by the impactor, IMHO]
Red Planet's Ancient Equator Located
Sarah Graham
Scientific American
April 20, 2005
Jafar Arkani-Hamed of McGill University discovered that five impact basins--dubbed Argyre, Hellas, Isidis, Thaumasia and Utopia--form an arclike pattern on the Martian surface. Three of the basins are well-preserved and remain visible today. The locations of the other two, in contrast, were inferred from measurements of anomalies in the planet's gravitational field... a single source--most likely an asteroid that was initially circling the sun in the same plane as Mars--created all five craters. At one point the asteroid passed close to the Red Planet... and was broken apart by the force of the planet's gravity. The resulting five pieces subsequently slammed into Mars along its then equator. The center of the circle inscribed by the five craters, which marks the planet's ancient south pole, lies at present day latitude -30 and longitude 175.

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