If indeed there ever life on Mars, then the last habitat of life on Mars should be under the surface soil of Mars. This study is the result of a NASA study.
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| Mars clay (NASA) |
Mapping more than 350 different locations on Mars that were tested by the European and Mars suggests that water abundance on Mars only lasts a very short period. This period occurs before the period hundreds of millions years ago where warm water interacts with rocks below the surface of Mars. Then, is there life on Mars, and how about the atmosphere of Mars can be changed.
"The types of clay minerals that formed in the shallow subsurface are all over Mars," said John Mustard, professor at Brown University in Providence, R.I. Mustard is a co-author of the study in the journal Nature. "The types that formed on the surface are found at very limited locations and are quite rare."
Discovery of clay minerals on Mars in 2005 indicated the planet once hosted warm, wet conditions. If those conditions existed on the surface for a long era, the planet would have needed a much thicker atmosphere than it has now to keep the water from evaporating or freezing. Researchers have sought evidence of processes that could cause a thick atmosphere to be lost over time.
This new study supports an alternative hypothesis that persistent warm water was confined to the subsurface and many erosional features were carved during brief periods when liquid water was stable at the surface.
"If surface habitats were short-term, that doesn't mean we should be glum about prospects for life on Mars, but it says something about what type of environment we might want to look in," said the report's lead author, Bethany Ehlmann, assistant professor at the California Institute of Technology, Pasadena, and scientist at NASA's Jet Propulsion Laboratory, also in Pasadena. "The most stable Mars habitats over long durations appear to have been in the subsurface. On Earth, underground geothermal environments have active ecosystems."
Observation of clay minerals using the OMEGA spectrometer derived from the orbiter's European Space Agency's Mars Express. The results from the spectrometer showed additional evidence of Martian liquid water. Clays form from the interaction of water with rock. Different types of clay minerals result from different types of wet conditions. That Clay minerals form where the ratio of water interacting with rock is small Generally retain the same chemical elements as Those found in the original Altered volcanic rocks by the water later. The study interprets this to be the case for most terrains on Mars with iron and magnesium clays. In contrast, surface environments with higher ratios of water to rock can alter Further rocks. Soluble elements are Carried off by water, and different aluminum-rich clays form.
Another clue is obtained from the detector was the discovery of a mineral called prehnite. These minerals formed at temperatures above 200 degrees Celsius (or about 400 degrees Fahrenheit). This temperature is typical of hydrothermal environment in underground rather than surface water. "Our interpretation is a shift from thinking That the warm, wet environment was Mostly at the surface to thinking it was Mostly in the subsurface, with limited exceptions," said Scott Murchie of the Johns Hopkins University Applied Physics Laboratory in Laurel, Md.., a co-author of the report and principal investigator for CRISM. One of the exceptions may be Gale Crater, the site targeted by NASA's Mars Science Laboratory mission. Launching this year, the rover mission's Curiosity Will Investigate layers That land and contain clay and sulfate minerals.
NASA's Mars Atmosphere and Volatile Evolution mission, or MAVEN, in development for a 2013 launch, may Provide Evidence for or against this new interpretation of the Red Planet's environmental history. The report Predicts MAVEN Findings consistent with the atmosphere not having been thick enough to Provide warm, wet surface conditions for a prolonged period.
Source: NASA
Source: NASA
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