Dried-up sea beds found on Mars 

NASA scientists have discovered ancient sea or lake beds on the surface of Mars that could once have harboured life, writes Jonathan Leake.

The discovery is among the most significant concerning Mars so far, because such places are the most likely locations for fossils or other signs of past life.

Nasa will announce the discovery in this week's edition of Science with the suggestion that the next generation of Mars landings should be sent to such areas.

This weekend a British group building a craft bound for Mars said it was already considering rerouting its vehicle, Beagle II, to land in the middle of one of the newly discovered sea beds.

Professor Colin Pillinger, an astronomer at the Open University who heads the Beagle II project, will also announce that he has raised the full £30m needed for the British mission.

He has just been offered £9m by the European Space Agency, with the rest coming from commercial sponsors. "We will launch in June 2003 and hope to land on Mars on Boxing Day," he said.

The Nasa discovery is based on images taken by Mars Global Surveyor, which has been orbiting the red planet for more than a year.

It is said to have sent back detailed pictures of rocks that could only have been created by sedimentation, in which particles sink to a sea bed and are compressed into rock.

-- Uncle Bob (unclb0b@aol.com), December 03, 2000

Answers

>> It is said to have sent back detailed pictures of rocks that could only have been created by sedimentation, in which particles sink to a sea bed and are compressed into rock. <<

Wind can deposit sediments, not just water. Once sediments are in place, pressure is all that is required to turn them into rock. The weight of a sea and overlaying sediments often exert such pressure on Earth. However, sediments could conceivably be lithized by the weight of other rock. Evidence of wave action would be much firmer evidence of water gathered in seas.

Damn all science news reporters. They always wash out the details from their science reporting until you can't figure out what is what.

-- Brian McLaughlin (brianm@ims.com), December 03, 2000.