WORLD
Further evidence that Mars once had oceans emerges
Baku, February 15 (AZERTAC). The European Space Agency (ESA) has provided more evidence that suggests the surface of Mars was once home to an ocean. Featuring ground-penetrating radar capabilities, the MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding) radar aboard the ESA`s Mars Express spacecraft has detected sediments like that seen on an ocean floor.
In 1877, with the aid of a 22 cm (8.6 in) telescope, Italian astronomer Giovanni Sciaparelli produced the first detailed map of Mars, which featured what he called canali. Although canali actually means "channels" in English, it was popularly mistranslated as "canals," which, along with books by Percival Lowell, helped foster the popular notion of water and life - including Martians - on the Red Planet`s surface. Although these "canals" were later proven to be an optical illusion, these myths weren`t dispelled until NASA`s Mariner missions in the 1960`s.
Yet more recent mapping efforts still point to there being liquid water on the planet`s surface at some point in its history. It is within the boundaries of features tentatively identified in images from various spacecraft as shorelines that MARSIS detected sedimentary deposits reminiscent of an ocean floor.
"MARSIS penetrates deep into the ground, revealing the first 60 - 80 meters (197 - 262 ft) of the planet`s subsurface," says Wlodek Kofman, leader of the radar team at the Institut de Planétologie et d`Astrophysique de Grenoble (IPAG). "Throughout all of this depth, we see the evidence for sedimentary material and ice."
The sediments detected by MARSIS are areas of low radar reflectivity, which typically indicates low-density granular materials that have been eroded away by water and carried to their final resting place.