SETI bioastro: A new blow to Life on Mars

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From: LARRY KLAES (ljk4@msn.com)
Date: Fri Dec 06 2002 - 08:35:06 PST


Q: IS THERE REALLY LIFE ON MARS? A: NO

>From Scotsman, 6 December 2002

http://www.news.scotsman.com/scitech.cfm?id=1356332002

ALASTAIR DALTON SCIENCE CORRESPONDENT

THE possibilities of life on Mars have long fascinated authors and
musicians, from HG Wells to David Bowie.

However, a British mission supported by Damien Hirst and Blur could be in
for disappointment when it touches down on the Red Planet next Christmas.

New research published today suggests that the question to the oft repeated
refrain, "Is there life on Mars?" is simple: "No."

Mars is an unpromising place for supporting life because it is a cold, dry
planet that only became warm and wet for short periods while being bombarded
by water-filled asteroids, US scientists claim.

They believe Mars is even less hospitable than previously thought - because
the scalding rains from the asteroid impacts which carved vast gullies into
the surface were followed by long icy droughts.

However, the Beagle 2 team, whose landing craft blasts off for Mars next
May, can take heart from other experts who believe volcanic activity may
have created underground water pools conducive to life.

The mission, which is named after the ship which took Charles Darwin on his
voyage of discovery, has again sparked the imagination of artists who follow
on from HG Wells, who wrote The War of the Worlds, about a Martian invasion
of Earth, and David Bowie who recorded the Life on Mars album.

Beagle 2's search for life will be aided by an instrument calibration chart
and sample colour guide painted by Damien Hirst, while a musical call sign
to Earth has been composed by members of Blur.

Dr Teresa Segura, of the University of Colorado, at Boulder, who led the new
research, said it rejected previous theories that Mars' network of valleys
were formed in a long-lasting greenhouse climate that teemed with life in
warm, wet conditions.

She explained: "In contrast, we envision a cold, dry planet; an almost
endless winter broken by episodes of scalding rains followed by flash
floods.

"Only during the brief years or decades after the impact events would Mars
have been temperate, and only then might it have bloomed with life. "

However, Dr Segura added: "The short duration of the warm episodes may have
made it challenging for life to establish itself on Mars in the first
place."

The researchers used photographs of Mars and computer simulations to build
up a detailed picture of its past.

Their study, which is published in the journal Science, concluded that huge
asteroids up to 150 miles in diameter pounded Mars almost four billion years
ago. The impacts emptied vast quantities of water on to the surface and
released powerful blast waves of more than 2,200C that melted underground
ice deposits.

The network of valleys also created were claimed, in 1906 by the American
astronomer Percival Lowell, to be canals constructed by Martians.

Dr Owen Toon, a member of the research team, said: "The atmosphere would be
hotter than a self-cleaning oven. When the water was released from the
atmosphere, it would fall as scalding rain."

The scientists have estimated more than 150ft of water fell in some areas,
followed by many decades of rainfall of 6ft a year.

Dr Toon said the volume of water would have carved features into Mars's
surface, but between impacts, the planet would have cooled into a dry,
chilly desert.

Dr Peter Smith, a planetary scientist at the University of Arizona, said
that if warmth and liquid water were available on Mars for only intermittent
periods "then you have a pretty gloomy picture for life".

However, he said there were other forces on the planet, particularly
volcanic action, that may have created subsurface pools of water where
microscopic life could have lived.

He said: "In my opinion, they haven't closed the book on the prospects for
the evolution of life on Mars."

Dr Ronald Greeley, a planetary researcher at Arizona State University,
agreed the latest findings were not conclusive. He said the study "doesn't
put a nail in the coffin" for the evolution of life on Mars because
hydrothermal systems powered by volcanic action and underground salt-water
pools may still exist and would be favourable for the evolution of life.

Professor Colin Pillinger, the lead scientist for the Beagle 2 mission,
brushed off the latest claims as irrelevant: "This does not reduce the
chances of life. We know there have been large amounts of water on Mars for
three million years.

"This will not stop us from sending a craft there to look for life. There is
still clear evidence from a Martian meteorite that liquid water is trickling
around. A little water is all you need for micro-organisms."

Other scientists believe life may have survived deep underground, following
the discovery of microbes several miles beneath the Earth's surface.

An exhibition about the two Beagle expeditions opens at the National
Maritime Museum, in London, today and runs until September.

Copyright 2002, scotsman.com

==================
(5) IF MARTIANS DON'T EXIST, THEY STILL INHABIT THE COUNTRY OF OUR MINDS

>From The Times, 6 December 2002
http://www.timesonline.co.uk/article/0,,542-504252,00.html

Life on Mars
Scientists can't take the Martians out of our minds

It is a truth universally acknowledged that a planet as near our own Earth
as Mars is in need of little green men to live on it and visit us. Ever
since mankind realised that the stars that filled the night skies were an
infinite number of other planets, suns and galaxies, the belief that we are
the only intelligent life form in that empty, spinning universe has made us
feel a little lonely. When we look at the heavens, it's natural to hope that
companionship might be somewhere out there. And where better to find it than
in the reddish glow of the closest planet, so instantly visible that
Classical writers likened it to the fiery, belligerent god of war, which
stands brilliantly out against paler, remoter stars to this day?

Now the latest scientific research says it is unlikely life could ever have
existed on Mars. Its frozen oceans may have melted, briefly, whenever
asteroids smashed into the red planet - but not for long enough to breed the
microbes and micro-organisms that might, eventually, have turned into short,
tubby men with glistening green skin, lots of limbs and eyeballs on stalks.

That may be fact. But it's a churlish kind of science that denies us the
pleasure of believing that these cosmic cousins are waiting in space for us
to find them.

Our need for Martians stretches back through the centuries to the
philosopher Immanuel Kant. In 1755, he pictured them as "light, wispy
creatures" with intellects more powerful than ours. A century later, the
Italian astronomer Giovanni Schiaparelli observed about 100 "canali"
(Italian for "channels") on the surface of Mars; astronomers decided they
might be huge bands of vegetation bordering irrigation ditches dug by
intelligent beings to carry water from Mars's polar ice-caps.

H.G. Wells also fantasised about meetings with men from space, though
Wells's Martians were an altogether feistier bunch of 20th-century horrors
with tentacles and death rays trained on the residents of Surrey. C.S. Lewis
made them over in religious shape, and created languages for both the shaggy
round seal-like ones and the very tall skinny ones.

The descendants of all these Martians still populate the films,
science-fiction novels and cartoons of today. We know their every little
way. Modern Martians travel by UFO. They wear skin-tight, streamlined,
silvery uniforms. They're obsessed with meeting people's leaders (no messing
about with middle management for them). And they pop up in pop psychology
books (masquerading as human men). If Martians don't exist, it's not because
we haven't done our best to invent them. So what if they only inhabit the
country of our minds?

Copyright 2002 Times Newspapers Ltd.


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