Dating may tubig sa Mars

ANG Mars ay dating natatakpan ng tubig sa matagal na panahon, ibig sabihin ay maaaring may nabuhay roon kamakailan lamang, ayon sa mga siyentista.

Bunsod ng lighter-toned bedrock sa paligid ng mga bitak sa ibabaw, masasabing ang red planet ay matagal nang may likido dahil may naiwan ditong “halo-like rings” ng silica.

Ang bagong natuklasang ito ay iniulat sa inilathala sa Geophysical Research Letters, journal ng American Geophysical Union.

Sinabi ni Jens Frydenvang, siyentista sa Los Alamos National Laboatory at University of Copenhagen at lead author ng inilathala, “The concentration of silica is very high at the centrelines of these halos.

“What we’re seeing is that silica appears to have migrated between very old sedimentary bedrock and into younger overlying rocks.

“The goal of NASA’s Curiosity rover mission has been to find out if Mars was ever habitable, and it has been very successful in showing that Gale crater once held a lake with water that we would even have been able to drink, but we still don’t know how long this habitable environment endured.

“What this finding tells us is that, even when the lake eventually evaporated, substantial amounts of groundwater were present for much longer than we previously thought.

“Thus, further expanding the window for when life might have existed on Mars.”

Gayonman, hindi malinaw kung ang tumagal ang nabubuhay roon dahil sa groundwater.

Ang “halos” ay inanalisa ng rover’s science payload, gayondin ng laser-shooting Chemistry and Camera (ChemCam) instrument, na ini-develop sa Los Alamos National Laboratory, at ng French space agency.

Naglakbay ang Curiosity nang mahigit 16 km sa 1,700 sols, martian days mula sa ilalim ng Gale crater part patungo sa Mount Sharp, sa gitna nito.

Ginamit  ng mga siyentista ang lahat ng data na nakolekta ng ChemCam upang pagsama-samahin para sa higit na “complete picture” ng geological history ng Mars.

Ang elevated silica sa “halos” ay natagpuan “over approximately 20 to 30 metres in elevation” malapit sa rock-layer ng ancient lake sediments na mayroong high silica content.

Dagdag ni Dr. Frydenvang, “This tells us that the silica found in halos in younger rocks close by was likely remobilised from the old sedimentary rocks by water flowing through the fractures.”

(mirror.co.uk)