Scientists are expressing confidence that questions about life on
Mars, which have captured human imagination for centuries, finally may
be answered, thanks in part to new life-detection tools up to 1,000
times more sensitive than previous instruments.
This artist concept features NASA's Mars Science Laboratory Curiosity rover, a mobile robot for investigating Mars' past or present ability to sustain microbial life. Curiosity is being tested in preparation for launch in the fall of 2011. Image Credit: NASA/JPL-Caltech
"The bottom line is that if life is out there, the high-tech tools of
chemistry will find it sooner or later," said Jeffrey Bada, Ph.D.,
co-organizer of a special two-day symposium on the Red Planet, which
began in Denver, Colorado, on August 30th during the 242nd National
Meeting & Exposition of the American Chemical Society (ACS). "It
certainly is starting to look like there may be something alive out
there somewhere, with Mars being the most accessible place to search,"
The symposium includes more than two dozen presentations by experts
concerned with whether life exists, or existed, on Mars. Abstracts from the symposium can be found here.
"One reason that the questions linger is that they haven´t had the
right instruments," said Bada, a noted authority on the topic at the
Scripps Institution of Oceanography at the University of
California-San Diego. "We have the instruments now or are in the
process of developing and refining them. The challenge is getting them
onboard future spacecraft, knowing what kinds of compounds to look for
and knowing exactly where to look."
Bada is a strong advocate for postponing future manned missions to
Mars until the unmanned missions get enough information to land
astronauts in an area most hospitable to life. He expressed concern,
however, that NASA budget cuts could jeopardize such future unmanned
One forthcoming unmanned mission is the new Mars Science Laboratory
rover, called Curiosity, scheduled for launch in November. The $2.5
billion nuclear-powered machine will land on Mars´ surface with a
suite of 10 science instruments to try to determine if conditions are
favorable for life. Another key Mars mission is scheduled for 2016.
Called the ExoMars Trace Gas Orbiter, it will carry five science
instruments and will study gases in Mars´ atmosphere, including
methane, for evidence of biological or geological activity. It is a
joint mission of the European Space Agency and NASA.
MSL features in Issue 2 of the Astrobiology Program's graphic history, Astrobiology: The Story of Our Search for Life in the Universe
. Issues 1 and 2 are available here
. Image Credit: Aaron L. Gronstal/NASA Astrobiology
"The instruments on that atmospheric mission have a factor of 100 to
1,000 increase in sensitivity over what is currently available from
Mars orbiters or from ground observations," noted symposium
co-organizer Mark Allen, Ph.D., who is the U.S. project scientist for
the 2016 Mars mission. He is with the Jet Propulsion Laboratory at the
California Institute of Technology in Pasadena.
Among the most important instruments flown onboard future missions
will be those that can detect organic nitrogen, Bada said. Nitrogen is
essential for life on Earth. Scientists are convinced that if there´s
life on Mars, it will contain nitrogen.
Scientists also should look for signs of life deep underneath Mars´
surface, Bada said. He noted that powerful ultraviolet and cosmic rays
have bombarded the planet´s surface for billions of years, likely
destroying organic matter so that traces of these materials are no
longer detectable. But studies suggest that organic materials buried
beneath the surface of Mars, perhaps a meter or so deep, may somehow
be protected against this radiation.
Researchers are also planning to use high-tech instruments to search
Mars´ atmosphere for signs of life. Among the substances they´ll be
searching for in the future is methane, the largest component of
natural gas. NASA scientists have reported that Mars appears to be
emitting plumes of methane on parts of the planet. If so, scientists
suggest that the possible sources include bacteria and other