Mars Is Drier Than Expected

The surface areas of Mars are colored blue to show lots of subsurface hydrogen, indicating the presence of water.

A spacecraft orbiting Mars has discovered deposits of ice at its south pole so thick that they would cover the planet in 36 feet of water if they were melted, said scientists. The scientists used the joint NASA-Italian Space Agency radar instrument on the European Space Agency Mars Express spacecraft to estimate the thickness and volume of ice deposits at the Martian south pole. These ice deposits cover an area larger than Texas.

The deposits, up to 2.3 miles thick, are under a polar cap of white frozen carbon dioxide and water, and appear to be composed of at least 90 percent frozen water, with dust mixed in, according to findings published in the journal Science.

Scientists have known that water exists in frozen form at the Martian poles, but this research produced the most accurate measurements of just how much there is.

They are eager to learn about the history of water on Mars because water is fundamental to the question of whether the planet has ever harbored microbial or some other life. Liquid water is a necessity for life as we know it.

Characteristics like channels on the Martian surface strongly suggest the planet once was very wet, a contrast to its present arid, dusty condition.

But researchers are baffled by what happened to the water -- perhaps only 10 percent of the water that once existed on Mars is now trapped in the polar ice caps.

"Even if you took the water in these two (polar) ice caps and added it all up, it's still not nearly enough to do all of the work that we've seen that the water has done across the surface of Mars in its history."

Cited story.

Image source.


tags: ,

More like this

A newly found, buried deposit of frozen carbon dioxide -- dry ice -- near the south pole of Mars contains about 30 times more carbon dioxide than previously estimated to be frozen near the pole. This map color-codes thickness estimates of the deposit derived and extrapolated from observations by…
The Mars Reconnaissance Orbiter has acquired data that seems to indicate that Mars has dry-ice snowfalls. From a press release by NASA: Frozen carbon dioxide, better known as "dry ice," requires temperatures of about minus 193 degrees Fahrenheit (minus 125 Celsius), which is much colder than…
"Mars once was wet and fertile. It's now bone dry. Something bad happened on Mars. I want to know what happened on Mars so that we may prevent it from happening here on Earth." -Neil deGrasse Tyson Oh, it's true alright, something bad did once happen on Mars. And although there isn't any real…
Below is the second part of my interview with planetary geologist Bethany Ehlmann. In the first part, she discussed two of her recent papers on Martian geology (see citations below). In this segment, she discusses water on Mars more generally. Bethany Ehlmann Nick Anthis: Would it be possible to…