By Xinhua
Washington : The U.S. National Aeronautics and Space Administration (NASA) announced on Thursday that its Mars Odyssey orbiter has found evidence of salt deposits on Mars, giving hope that the environment could have supported primitive life.
These deposits point to places where water once was abundant and where evidence might exist of possible Martian life from the red planet’s past, said NASA on its website.
A team led by Mikki Osterloo of the University of Hawaii found approximately 200 sites, ranging from about a square km to 25 times that size on southern Mars that show spectral characteristics consistent with chloride minerals.
Chloride is part of many types of salt, such as sodium chlorideor table salt.
“They could come from groundwater reaching the surface in low spots,” Osterloo said. “The water would evaporate and leave mineral deposits, which build up over years. The sites are disconnected, so they are unlikely to be the remnants of a global ocean.”
Osterloo’s team reported the findings in the March 21 issue of the journal Science. They think the salt deposits formed approximately 3.5 billion to 3.9 billion years ago, while several lines of evidence suggest Mars then had intermittent periods with substantially wetter and warmer conditions than today’s dry, frigid climate.
Scientists looking for evidence of past life on Mars have focused mainly on a handful of places that show evidence of clay or sulfate minerals.
Clays indicate weathering by water, and sulfates may have formed by water evaporation. The new research, however, suggests an alternative mineral target to explore for biological remains.