Life possible on 'large parts' of Mars
Australia: Australian scientists who modelled conditions on
Mars to examine how much of the red planet was habitable said Monday
that "large regions" could sustain terrestrial life.
Charley Lineweaver's team, from the Australian National University,
compared models of temperature and pressure conditions on Earth with
those on Mars to estimate how much of the distant planet was liveable
for Earth-like organisms.
While just one percent of Earth's volume - from core to upper
atmosphere - was occupied by life, Linewaver said their world-first
modelling showed three percent of Mars was habitable, though most of it
was underground.
"What we tried to do, simply, was take almost all of the information
we could and put it together and say 'is the big picture consistent with
there being life on Mars?'," the astrobiologist told AFP.
"And the simple answer is yes... There are large regions of Mars that
are compatible with terrestrial life."
Where previous studies had taken a "piecemeal" approach by examining
particular sites on Mars for signs of life, Lineweaver said his research
was a "comprehensive compilation" of the entire planet using decades of
data.
Frozen water has been found at the poles on Mars and the ANU study
examined how much of the planet could sustain water "that could be
habitable by Earth-like standards by Earth-like microbes".
The low-pressure environment of Mars means water cannot exist as a
liquid and will vaporise on the surface, but Lineweaver said the
conditions are right underground, where the weight of the soil gives the
added pressure required.
It would also be warm enough, at certain depths, for bacteria and
other micro-organisms to thrive due to heat from the planet's core. The
average surface temperature on Mars is minus 63 degrees Celsius (minus
81 Fahrenheit).
AFP |