Organic matter found on Mars, Nasa reveals in major announcement
Nasa’s Curiosity rover
has found organic matter preserved on Mars, in a discovery that could suggest
it was once home to life. The molecules
represent an intriguing suggestion that Mars has been far more alive than we
ever knew. While the discovery does not shed light on whether Mars was once
home to alien life, and whether it could still be, the findings could
be the result of ancient life there.
“The chances of being
able to find signs of ancient life with future missions, if life ever was
present, just went up,” said Curiosity’s project scientist, Ashwin Vasavada of
Nasa’s Jet Propulsion Laboratory in Pasadena, California. Experts say that the
findings should propel us to look for conclusive evidence of alien life living
on the planet.
“With these new
findings, Mars is telling us to stay the course and keep searching for evidence
of life,” said Thomas Zurbuchen, associate administrator for the Science
Mission Directorate at Nasa headquarters in Washington. “I’m
confident that our ongoing and planned missions will unlock even more
breathtaking discoveries on the Red Planet.” The new announcement
is actually the result of two new studies that reveal vast detail
about how methane exists on the planet, as well as the unexpected organic
molecules that are preserved in its soil.
And one team has made
a significant breakthrough in our attempt to understand the ancient organic
matter on Mars, which could help us discover whether the world was once
habitable and what happened to it in the billions of years since. The surface of Mars is
inhospitable today. But in the past, it almost certainly had liquid water,
which could have helped fuel life there. The Curiosity rover
has headed to an area that was thought to once have been a large lake of that
water, inside Gale Crater.
It was inside that hole where scientists found the
new findings, which suggest the water lake had all the necessary
ingredients for life – from chemical building blocks to the energy sources
required to sustain life. The two studies appear
in the journal Science. In a companion article, an outside expert
describes the findings as “breakthroughs in astrobiology”. “The question of
whether life might have originated or existed on Mars is a lot more opportune
now that we know that organic molecules were present on its surface at the
time,” wrote Utrecht University astrobiologist Inge Loes ten Kate of the
Netherlands. Kirsten Siebach, a
Rice University geologist who was also not involved in the studies, is equally
excited. She said the discoveries break down some of the strongest arguments
put forward by life-on-Mars sceptics, herself included.
“The big takeaway is
that we can find evidence. We can find organic matter preserved in mudstones
that are more than 3 billion years old,” Ms Siebach said. “And we see releases
of gas today that could be related to life in the subsurface, or at the very
least are probably related to warm water or environments where Earth life would
be happy living.” The methane
observations provide “one of the most compelling” cases for present-day life,
she said. Scientists have long
been baffled by the discovery of significant amounts of methane on Mars. On
Earth, most methane is produced by biological sources, leading to
hopes the Red Planet is more alive than we had thought.
The new data
suggests the methane is being stored underneath the surface of the planet.
Seasonal changes appear to bring that methane out and onto the surface, where
it has been detected by Curiosity, suggest the scientists. Another piece of
research published simultaneously shows that intriguing organic molecules have
been found in ancient rock on Mars. Curiosity took new samples and heated them
so that it could analyse the molecules that were released – and the data showed
there is certain matter similar to the kind of organic-rich rock found on
Earth.
