Ancient mega-tsunamis hint at cold Martian oceans

And where there were cold oceans, there could well have been life.


3.4 billion years ago, a meteorite smashed into the northern plains of Mars, where an ancient ocean once stood. Its impact threw up a massive wall of liquid water that scarred the surrounding landscape with backwash channels as the water poured back into the Martian sea. A few million years later, after the Red Planet had cooled significantly, another huge chunk of space rock tore into Mars -- however, this time, the resulting tsunami was made of ice blobs that simply stuck wherever they landed rather than return to the sea.

The difference in tsunamis isn't simply a result of a cooling planet, they're evidence that Mars' early water works were capable of sustaining life, according to a newly released study from the Center of Astrobiology, Madrid.

"Our paper provides very solid evidence for the existence of very cold oceans on early Mars," principal investigator and visiting Cornell professor, Alberto Fairén said in a statement. "It is difficult to imagine Californian beaches on ancient Mars, but try to picture the Great Lakes on a particularly cold and long winter, and that could be a more accurate image of water forming seas and oceans on ancient Mars."

Frosty white water ice clouds and swirling orange dust storms above a vivid rusty landscape reveal Mars as a dynamic planet in this sharpest view ever obtained by an Earth-based telescope. The Earth-orbiting Hubble telescope snapped this picture on June 26, when Mars was approximately 43 million miles (68 million km) from Earth - its closest approach to our planet since 1988. Hubble can see details as small as 10 miles (16 km) across. Especially striking is the large amount of seasonal dust storm activity seen in this image. One large storm system is churning high above the northern polar cap [top of image], and a smaller dust storm cloud can be seen nearby. Another large duststorm is spilling out of the giant Hellas impact basin in the Southern Hemisphere [lower right]. Acknowledgements: J. Bell (Cornell U.), P. James (U. Toledo), M. Wolff (Space Science Institute), A. Lubenow (STScI), J. Neubert (MIT/Cornell)

What's more, those icy lobes could provide key insights into whether Mars ever hosted life. "Cold, salty waters may offer a refuge for life in extreme environments, as the salts could help keep the water liquid. ... If life existed on Mars, these icy tsunami lobes are very good candidates to search for biosignatures," he continued. To that end, the researchers hope to conduct follow-up studies of the Martian terrain and identify areas of the northern plains for further investigation.