London: NASA is set to launch two new missions to investigate how mars, which could have once harboured life, turned hostile.
The Martian surface is incredibly hostile for life. The Red Planet’s thin atmosphere does little to shield the ground against radiation from the Sun and space.
Harsh chemicals, like hydrogen peroxide, permeate the soil. Liquid water, a necessity for life, can’t exist for very long here—any that does not quickly evaporate in the diffuse air will soon freeze out in subzero temperatures common over much of the planet.
It wasn’t always this way. There are signs that in the distant past, billions of years ago, Mars was a much more inviting place.
Martian terrain is carved with channels that resemble dry riverbeds. Spacecraft sent to orbit Mars have identified patches of minerals that form only in the presence of liquid water.
It appears that in its youth, Mars was a place that could have harboured life with a thicker atmosphere warm enough for rain that formed lakes or even seas.
Two new NASA missions, one that will roam the surface and another that will orbit the planet and dip briefly into its upper atmosphere, will try to discover what transformed Mars.
“The ultimate driver for these missions is the question, did Mars ever have life?” said Paul Mahaffy of NASA’s Goddard Space Flight Center in Greenbelt, Md.
“Did microbial life ever originate on Mars, and what happened to it as the planet changed? Did it just go extinct, or did it go underground, where it would be protected from space radiation and temperatures might be warm enough for liquid water?” he stated.
The Mars Science Laboratory (MSL) mission features Curiosity, the largest and most advanced rover ever sent to the Red Planet.
The Curiosity rover bristles with multiple cameras and instruments, including Goddard``s Sample Analysis at Mars (SAM) instrument suite.
By looking for evidence of water, carbon, and other important building blocks of life in the Martian soil and atmosphere, SAM will help discover whether Mars ever had the potential to support life.
Scheduled to launch in late November or December 2011, Curiosity will be delivered to Gale crater, a 96-mile-wide crater that contains a record of environmental changes in its sedimentary rock, in August 2012.
The Mars Atmosphere and Volatile EvolutioN (MAVEN) mission, scheduled to launch in late 2013, will orbit Mars and is devoted to understanding the Red Planet’s upper atmosphere.
It will help determine what caused the Martian atmosphere—and water— to be lost to space, making the climate increasingly inhospitable for life.
“Both MAVEN and Curiosity/SAM will determine the history of the Martian climate and atmosphere using multiple approaches,” said MAVEN Principal Investigator Bruce Jakosky of the University of Colorado’s Laboratory for Atmospheric and Space Physics.