Scientists have discovered an 18-square-mile salt flat on the surface of cold, dry Mars, writes Nature World News.

The discovery indicates that the Red Planet once possessed a habitable body of water that existed on this spot, according to researchers at the University of Colorado, Boulder.

The remaining dry bed of the former lake measures roughly the size of the city of Boulder, Colorado. It lies in the Red Planet’s Meridiani region, which is located nar to where the Mars Opportunity rover first touched down. Large-scale deposits, like Earth’s Bonneville Salt Flats, in Utah, which measures about 46 square miles—are usually evidence of evaporated bodies of water, according to a press release.

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There’s something weird about that picture

dv said:

There’s something weird about that picture

Yes there is. Try this one:

“mineralogical analysis of the features surrounding the deposit indicate that this one-time lakebed is no older than 3.6 billion years old … Based on the extent and thickness of the salt, the researchers estimate that the lake was only about 8 percent as salty as the Earth’s oceans”.

mollwollfumble said:

Yes there is. Try this one:

That’s better.

> Based on the extent and thickness of the salt, the researchers estimate that the lake was only about 8 percent as salty as the Earth’s oceans.

That 8% assumes that the lake only ever filled up once. If it filled twice then 4% as salty, etc.

I can’t help wondering how long that lake was in existence for. A minimum time ought to be calculable. It couldn’t fill in under 2.5 hours or so. But I’d guess it would need a lot longer than that to evaporate. 3 or 4 days minimum I think. That’s not a reliable calculation.

Another possibility is that it was filled not with liquid water but with snow. It snows on Mars quite frequently. In that case it would have filled up many times because snow doesn’t have much salt in it.

That 8% assumes that the lake only ever filled up once. If it filled twice then 4% as salty, etc.
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But when it fills, the deposited salt will dissolve.