Looking for Life on Mars
I know that back in the day people assumed there were martians, and radio stations broadcast invasions of little green men... But nowadays we know there are no martians... but that in order for life to exist on a planet (that we know and understand), water has to exist. The AP article “more evidence found for water on Mars” in the Naples Daily News (02/16/08) even reminded us that “the presence of water would raise the possibility of at least primitive life forms existing on the planet.” Now, scientists at NASA have recently discovered that there may be evidence of where water flowed on Mars. But recently, NASA’s Mars reconnaissance Orbiter spacecraft have taken images of dark- and light-toned rock inside of a giant rift valley, which would indicate layering of different sediments from past water flow.
These findings were presented at the annual meeting of the American Association for the Advancement of Science in San Francisco. These finding were also published in the02/16/07 edition of the journal of Science.
These linear fractures, called “halos” of lighter rick, indicate where fluids (probably water) passed through the bedrock. It is minerals that are in the fluid that bleach the rock, as well as strengthen it, making it more resistant to erosion.
Scientists also speculate with visible in these layers is evidence of cyclical weather patterns on Mars in the past, possibly from episodes of water, wind or volcanic activity.
They discovered December 2006 that there may be evidence of flowing water on Mars, through photography of changes in craters at different recent intervals, which showed evidence that water flowed on the planet as recently as a few years ago, and may possibly still be flowing there now.
When tens of thousands of gullies were previously found, scientists believed they were geographically young, carved from fast-moving water, rushing down sharp walls of deep craters. The two craters that were photographed in the Southern hemisphere were photographed again, from 1999 through 2005. They saw changes in the photographs consistent with water flowing down the walls.
Copyright © 2007 Janet Kuypers.
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Chicago Poet Janet Kuypers
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