From: Spudboy100@aol.com
Date: Sun May 26 2002 - 17:43:54 MDT
Sunday, 26 May, 2002, 14:08 GMT 15:08 UK Ice reservoirs found on Mars
http://news.bbc.co.uk/low/english/sci/tech/newsid_2009000/2009318.stm
By Dr David Whitehouse
BBC News Online science editor
Water-ice has been found in vast quantities just below the surface across
great swathes of the planet Mars. The finding by the American space agency
(Nasa) is undoubtedly one of the most important made about the Red Planet. It
solves one of its deepest mysteries, points the way for manned exploration
and reignites the question of whether life may exist on the planet. Insiders
suggest that, partly as a result of this finding, Nasa may now commit itself
to a manned landing within 20 years.
Where the water went The US space agency will make the dramatic announcement
about the water-ice next Thursday. And full disclosure of the findings will
come in the journal Science later that day. The discovery was made by the
Mars Odyssey spacecraft, which has been gathering data since late last year.
Mars water facts
Ice crystals less than one metre (three feet) below Mars surface
Located south of 60 degrees latitude
Melted, would create planet-wide ocean 500 metres deep
Nasa may commit to landing in less than 20 years
It confirms early observations that also pointed to enormous reservoirs of
ice just below the surface. This finding will answer a question that has
puzzled Mars researchers for decades: many lines of evidence suggest that the
Red Planet was water-rich in the past, so where did all that water go? The
answer appears to be that it is in the regolith - the layer of loose rock and
dust on the surface. Mars Odyssey has been returning high-quality data about
Mars' surface composition.
The spacecraft contains an instrument called a gamma-ray spectrometer that
looks for gamma-rays (high-energy light) with a specific signature showing
that they come from hydrogen less than one metre (three feet) beneath the
Martian surface. Astronomers believe that the hydrogen is locked up in
crystals of ice. Moon discovery The same design of instrument was used on the
Lunar Prospector spacecraft that discovered ice in the shadowed regions of
the Moon's poles in 1998. Also on board Mars Odyssey is a neutron
spectrometer that registers evidence for underground ice in the same regions
of the planet. Researchers were amazed at the strength of the signal of the
ice. They had expected to take a year to gather enough evidence but managed
to do so in just a few weeks.
They announced preliminary findings in March but now have good data
confirming large amounts of the water-ice just beneath the surface south of
60 degrees latitude.
Researchers suspect the same to be true of the northern hemisphere, but
cannot make the appropriate observations until later this year due to the
Martian winter in the north. Nasa scientists were scheduled to hold a major
news conference on Thursday when they would say that their earlier findings
had been confirmed and extended. But this may be brought forward after a
British newspaper leaked the news. Look for life The dramatic discovery may
also guide the selection of future landing and exploration sites on Mars, and
may suggest areas to look for evidence of past life. The presence of such a
vast amount of ice - if it were to melt it could cover the planet in an ocean
at least 500 metres deep (1,640 feet) - will change profoundly the direction
of future exploration. Although landing probes are planned - the European
Beagle 2 and Nasa's twin Mars rovers next year - neither are targeted at the
region where the ice may exist.
The Mars Polar Lander was to touch down in exactly the right spot in 1999 and
would have undoubtedly detected the ice had it not malfunctioned on the way
down. Having water just below the surface will be an enormous boon to
astronauts on Mars. Water is essential for life, so the discovery enhances
the belief that Mars could have had life in the past and perhaps in the
present as well. Because of this, bringing a sample of the ice and rock back
to Earth by an unmanned sample return probe will become a top priority.
This archive was generated by hypermail 2.1.5 : Sat Nov 02 2002 - 09:14:23 MST