The discovery of bright deposits on Mars, announced on 7 December 2006 by NASA, could indicate that liquid water has recently flowed on a few locations on the planet. The newly discovered deposits were identified by comparing different images of the same area taken by NASA’s Mars Global Surveyor (MOC camera), over a period of few years. The images suggest that water may have flowed there sometime within the past seven years. Photo Credit: NASA/JPL/Malin Space Science SystemsWashington, Mar 8: Deposits on Mars that originally appeared to be signs of an ancient ocean were instead produced by water emerging from underground, a new study has revealed.
According to the findings, the mineral deposits first discovered by the Mars rover Opportunity in 2004 could be attributed to the networks of springs and a shallow water table found on the Red Planet.
Scientists had previously thought the deposits were possible traces of water in lakes or oceans in Mars that existed for long before finally evaporating.
The study said that while he region where the deposits were found, known as Meridiani Planum, may at times have contained rivers and ponds in low-lying areas, it was no sea bed.
"Meridiani is one of the few regions of the planet where groundwater would be expected to reach the surface and evaporate to leave behind deposits of salts and evaporite minerals [minerals formed by the evaporation of water]," National Geographic quoted lead author Jeffrey Andrews-Hanna, of the Massachusetts Institute of Technology as saying.
For their study, the researchers used data on Martian topography and geology to model the likely distribution and movement of subsurface water over hundreds of millions of years.
The model showed that water might have traveled distances of up to 621 miles (1,000 kilometers) deep underground before finally spilling out at Meridiani.
The results also coincide with other findings, including satellite photographs showing networks of fractured rock through which underground water once flowed.
Steve Squyres, principal investigator for the Mars rover missions, said the new study "squared very well with both rover and orbital results".
"There is no closed basin at Meridiani, and so formation of significant evaporite deposits there requires that it be a region of groundwater upwelling," Squyres said.
Andrews-Hanna however, said the finding did not imply that ocean-like bodies of water were never present on Mars.
"Large amounts of water on the surface of Mars were certainly possible early in the planet's history. But as the planet dried, water would have been present only where the global-scale groundwater flow brought the water table to the surface," he said.
The findings will be published in tomorrow’s edition of the journal Nature. (ANI)