Scientists believe that they may soon discover lakes beneath the arid surface of Mars. Some of these subterranean pools could provide homes for primitive life forms.
Researchers’ hopes of finding liquid water on Mars have been raised by the dramatic discovery that Europe’s Mars Express has discovered evidence of ice on the planet’s surface only a week after turning on its instruments.
The discovery has sent European space scientists into raptures after having had their spirits dashed by the failure of Mars Express’s lander, Beagle 2, to communicate with Earth after its scheduled landing on Christmas Day.
”Finding anything that has to do with water on Mars is a sort of holy grail,” said David Southwood, science director of the European Space Agency. ”This is better than anything we’ve had so far.”
Ice was detected by two separate instruments on board the orbiting probe: Omega, which maps chemicals on the surface; and an instrument called a PFS, which studies the spectrum of molecules. Both began operating on 18 January.
However, the Mars Express instrument likely to provide the most exciting data has yet to be switched on. The Marsis radar altimeter, which is not scheduled for activation until April, will map the structure of Mars to a depth of several miles. Ancient caverns filled with water, which could provide homes for living beings, could be pinpointed this way.
”We know that microbes can survive in Antarctic ice at minus 40 degrees Celsius,” said Mars Express researcher Martin Siegert of Bristol University. ”Even at that temperature, water rich in chemicals forms at the boundaries between ice crystals and we have found bacteria there. However, the best prospects for life on Mars probably lie underground, where geothermal energy could keep water nice and warm.”
At the same time, scientists working on Mars Express’s high-resolution stereo camera will work on creating a 3D map of the entire planet by the year 2007. Using that, they will then be able to pinpoint the most promising surface sites to find water.
”Until now, we have only had flat, two-dimensional images of Mars,” said Professor Jan-Peter Muller of University College, London. ”Now we have pictures from which we can make positive geological predictions. This is going to change our understanding of the surface of the planet.”
The good fortune of Europe’s scientists contrasts with sudden gloom that has enveloped NASA engineers who were last night struggling to revive their ailing Mars rover, Spirit, and preparing for the landing of its twin, Opportunity, which was scheduled to touch down this morning.
Spirit, which together with Opportunity cost about R6,5-billion, began to malfunction on Wednesday, nearly three weeks after landing on Mars’s Gusev Crater and after sending back streams of data and pictures. For the following two days, it transmitted only sporadic beeps but began to transmit more coherent signals on Friday, though its prognosis remains uncertain.
”The chances that it will be perfect again are not good,” said project manager Pete Theisinger at NASA’s Jet Propulsion Laboratory. Even under the best of circumstances, the rover will not be back to normal for weeks, he added.
Spirit can stay in its current condition for some time while scientists work on its software problems, although, because the rover has remained switched on throughout the night when it should have been deactivated to conserve power, this could trigger further problems.
Engineers believe hardware damage has wreaked havoc with Spirit’s software, forcing it to reboot its computer 60 times. But Theisinger urged his team not to dwell on Spirit’s problems and to stay focused on Opportunity.
Its target is the Meridiani Planum, a dark grey region which is believed to be rich in the mineral grey haematite which typically forms in water-rich environments. However, Opportunity is unlikely to start investigating for a while.
Spirit took two weeks to roll on to the martian soil. Opportunity may take much longer as scientists react with heightened caution following their first rover’s breakdown, a delay that will reduce the three-month mission’s scientific returns. – Guardian Unlimited Â