Wednesday, 25 November 2009

The Red Planet was Once Blue... Giant Ocean Once Covered Third of Mars

A vast ocean once covered a third of Mars, scientists believe.
Such a stunning prospect greatly increases the chances of life having existed on the Red Planet, the fourth from the Sun in our solar system.

Researchers have come to the conclusion after using new software to analyse images of the surface. As a result, they have managed to find dozens of valleys to build up the most detailed map to date.

The valleys, first spotted in 1971, were caused by a network of rivers more than twice as extensive as previously mapped. The water channels were in a belt between the equator and mid-southern latitudes.

The experts from Northern Illinois University and Nasa believe they mark the paths of rivers that once flowed from the planet's southern highlands into a huge ocean in the north.

The evidence suggests that billions of years ago much of Mars had an 'arid continental climate' similar to drier areas of the Earth.

Rain would have fallen regularly, swelling the rivers and topping up the ocean basin. Such a wet period early in the planet's history would have greatly increased the chances of life.

Mars is still wet. The end of the article states that the planet is "bone dry" but this is not true. Evidence exists, seen in photos taken from the Mars rover missions, that indicates recent water flows. The remaining water today is trapped under the surface and occasionally flows to the surface in geysers. In many places the Rovers have been travelling over the bottom of long gone lakes and seas where there is salty mud. Rover tracks and digging reveals this to be true. In some photos you can see ice that has formed in wheel ruts.

Because of the lower gravity and the lack of water on Mars initially, when compared to Earth, the passing of billions of years has seen a reduction of water on Mars at a substantially greater rate than on Earth. See this:

Mars probably developed life like Earth (either separately or from Earth based microbial contamination) but the evolutionary process was hindered by the declining conditions.

I would not be surprised to find microbes, worms, plants, and perhaps some kind of very small crustaceans or hardy insects still alive. I am guessing that the evolutionary process would have favoured organisms that had adapted to the present conditions.

[Posted at the SpookyWeather blog, November 25th, 2009.]

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