RE: [ufodiscussion] The Threat From Life On Mars
- Great the more the merrier...Maybe one of their virus's will kill one of
From: Light Eye [mailto:universal_heartbeat2012@...]
Sent: Friday, December 03, 2004 3:21 AM
To: Global_Rumblings@...; SpeakIt@...;
Subject: [ufodiscussion] The Threat From Life On Mars
This is a 2 page article so click the link if you can't proceed to the next
Love and Light.
The threat from life on Mars
By Nigel Hawkes
Earths defences may need to be boosted against risk of potentially deadly
microbes returning on space probes
EARTH must take precautions to avoid contamination from lifeforms that must
now be presumed to exist on Mars, leading scientists gave warning yesterday.
Potentially deadly microorganisms could be returned to Earth on a probe
which is being planned to collect samples from the Martian surface.
NI_MPU('middle');The warning comes after a detailed scientific analysis of
data sent back by the roving vehicle Opportunity which landed on Mars on
Jeffrey Kargel of the US Geological Survey said that protection of our own
planet from alien forms of life requires the assumption that Martian life
exists. Before proceeding with sample returns or human missions to Mars, we
must review measures for planetary biological protection.
His warning appears in Science magazine in an article accompanying the first
formal publication of the mass of data from Opportunity, which continues to
operate on the Martian surface.
The search for life on Mars, now more than a century old, is still not
finally resolved. But the odds that life existed there and may still exist
are shortening, according to planetary experts, Dr Kargel said.
Nobody any longer expects Martian life forms to be anything like those on
Earth. But there remains a possibility that bacteria or other microscopic
organisms may survive in regions where there is still water. On Earth,
almost every imaginable habitat, including deep underground, has specialised
bacteria called extremophiles living and thriving.
The risks are twofold: probes sent from Earth may contaminate Mars with
terrestrial bacteria, wrecking future studies of Martian life; or, more
important, bacteria brought back from Mars may contaminate the Earth with
Similar precautions were taken at the time of the Apollo Moon landings.
Astronauts returned to Earth were kept in quarantine after they landed for
fear they might be infected with a lunar bug. None was.
Although the presence of water on the red planet can be considered proved,
of life there are only hints. One is the presence of the gas methane, which
might be produced by forms of life. On Earth, life can exist in areas as
acidic and salty as Meridiani Planum, where Opportunity landed examples
are the ancient mines of Rio Tinto in Andalucia, Spain, or the salty Permian
Basin in Texas. But few earthly species survive in environments that are at
the same time very cold, very acidic, and very salty and none that do
survive in such conditions produce methane.
But maybe on Mars they do, says Dr Kargel, the author of a recent book on
the latest ideas about Mars. Or maybe, he suggests, the organisms that
produced the Martian methane live in areas more hospitable than Meridiani
Analysing the data collected by Opportunity, a team led by the rovers
principal investigator, Dr Steve Squyres, of Cornell University, concludes
that the sedimentary rocks found by Opportunity preserve a record of
environmental conditions different from any on Mars today.
Liquid water was once present intermittently at the Martian surface at
Meridiani, and at times it saturated the subsurface, the team concludes.
Because liquid water is a prerequisite for life, we infer that conditions
at Meridiani may have been habitable for some period of time in Martian
Opportunity has explored two craters, Eagle and Endurance, near its landing
site. In both areas, layers in the bedrock showed that it had been laid down
as sediments, implying past oceans and voids in the rock were probably
caused by the dissolution of salt.
Opportunity also found quantities of small spheres, named blueberries
even though they are grey, not blue. These marbles consist of the iron-rich
mineral haematite. Similar spheres have been found in the deserts of
southern Utah, formed as iron-rich water seeped through sandstone.
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