The Mars Reconnaissance Orbiter has found evidence of hydrated silica or opal , a form of mineral, over large areas in the Martian surface, including in the large martian canyon called Valles Marineris . The discovery was made by the Compact Reconnaissance Imaging Spectrometer ( CRISM ) instrument on the orbiter. The findings are published by Ralph Milliken of Jet Propulsion Laboratory and other scientists in the November issue of the journal Geology . Opaline mineral deposits indicates widespread past presence of water on Mars Opaline minerals were first found recently on Mars by Spirit rover in the Gusev crater . The present find points to more widespread occurrence of the minerals in comparatively younger strata of Mars. The find indicates that liquid water might have been present on the surface of Mars for a longer time than previously thought. The previous view was that liquid water disappeared from the Martian surface three billion years ago. Now it is estimated that water could have been present as late as two billion years ago. Hydrated minerals such as opal that indicate presence of water is yet another evidence of presence of liquid water on Mars. Opal found on Earth's surface usually contain 3 – 10\% water, but can be as high as 20\%. Other water-bearing minerals found earlier are phyllosilicates and hydrated sulfates. Presence of liquid water is also suggested by suspected water-sculpted land forms on Mars, such as gullies and river channels. Currently water is present only as ice at both polar caps of Mars. "This is an exciting discovery because it extends the time range for liquid water on Mars, and the places where it might have supported life," said Scott Murchie, from John Hopkins University Applied Physics Laboratory in Maryland one of the co-authors.
The has found evidence of hydrated silica or , a form of mineral, over large areas in the Martian surface, including in the large martian canyon called . The discovery was made by the Compact Reconnaissance Imaging Spectrometer ( ) instrument on the orbiter. The findings are published by Ralph Milliken of Jet Propulsion Laboratory and other scientists in the November issue of the journal . Opaline mineral deposits indicates widespread past presence of water on Mars Opaline minerals were first found recently on Mars by in the . The present find points to more widespread occurrence of the minerals in comparatively younger strata of Mars. The find indicates that liquid water might have been present on the surface of Mars for a longer time than previously thought. The previous view was that liquid water disappeared from the Martian surface three billion years ago. Now it is estimated that water could have been present as late as two billion years ago. Hydrated minerals such as opal that indicate presence of water is yet another evidence of presence of liquid water on Mars. Opal found on Earth's surface usually contain 3 – 10\% water, but can be as high as 20\%. Other water-bearing minerals found earlier are and hydrated sulfates. Presence of liquid water is also suggested by suspected water-sculpted land forms on Mars, such as gullies and river channels. Currently water is present only as ice at both polar caps of Mars. "This is an exciting discovery because it extends the time range for liquid water on Mars, and the places where it might have supported life," said Scott Murchie, from in Maryland, one of the co-authors.
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Mars Reconnaissance Orbiter
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opal
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Valles Marineris
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CRISM
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Geology
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Spirit rover in the Gusev crater
in the
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phyllosilicates
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John Hopkins University Applied Physics Laboratory in Maryland
in Maryland,