A recent discovery has sent ripples through the science world, as ancient tsunamis have revealed potential life on Mars. The geologic shape of what used to be shorelines through Mars’ northern plains assures scientists that two large meteorites – striking the planet millions of years apart – triggered a pair of mega-tsunamis. The waves have left permanent scars on the landscape, revealing evidence of cold, salty oceans key to sustaining life.
“About 3.4 billion years ago, a big meteorite impact triggered the first tsunami wave. This wave was composed of liquid water. It formed widespread backwash channels to carry the water back to the ocean,” stated Alberto Fairén, Cornell visiting scientist in astronomy and principle investigator at the Centre of Astrobiology, Madrid. Fairén, along with Alexis Rodriguez of the Planetary Scientific, published their work in Scientific Reports (May 19), the journal is titled Nature.
Evidence was found for a second meteorite impact, which created the second tsunami wave. Between the two impacts, Mars went through extreme climate change, as water froze into ice, Fairén commented: “The ocean level receded from its original shoreline to form a secondary shoreline, because the climate has become significantly colder.” The second tsunami managed to form lobes of ice, which “froze on land and never went back to the ocean, which implies the ocean was at least partially frozen at the time”, he commented.
“Our paper provides very solid evidence for the existence of very cold oceans on early Mars. 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.”
John Bridges, a planetary scientist at Leicester University, who works on Nasa’s Curiosity rover mission believes evidence for a water-based Mars is increasing. “A consensus is quietly growing that there was a great sea, an ocean, on ancient Mars, and this is another take on it,” he stated.
Fairén concludes that “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”.