Mars as we know it is a inhuman , red desert but in the past tense , it might have had long - live water system feature , despite the wintry temperature . river , lakes , even a large sea may have once marked the surface of what we now think is a dry ( ormostlydry ) planet . And while there ’s no certainty about an ancient ocean yet , there ’s an increasing consistence of grounds .

Over the last 10 , detailed observationsfrom ballistic capsule revolve the Red Planet have provided more grounds of body of water - made structure on ancient Mars . In particular , scientist have spotted terrain known as " thumbprint terrain " near where they call up the ocean once live that they believe was formed by the chaotic force of displaced water , most likely from not one but two mega - tsunami . Mega - tsunami take issue from steady tsunami in that they are created by water being displaced rather than underwater tectonics . give the want of tectonics on Mars , worldwide scientist recall that these mega - tsunamis were due to meteor impact . Now researchers believe they have found the crater of at least one of them .

grant to inquiry issue inJournal of Geophysical Research : Planets , the Lomonosov Crater appears to have geological features reproducible with being the source of this type of event . The rim of the volcanic crater look like it was break-dance by water rushing back in . The comportment of these fractures on all sides make a potent fount for water induce in trying to fill the void left by the impact .

The crater itself is rough 120 kilometers ( 75 mile ) across and is surround by smooth young terrain , exchangeable to how it would have been as a likely shallow sea ocean bottom . According to the researchers , some 3 billion long time ago an target between 15 - 20 klick ( 9 - 12 miles ) across bear on the northerly cerebral hemisphere of Mars , hitting the coastline and generating a huge tidal waving .

There are other pieces of evidence regarding this and other ancient tsunamis left as scars on the aerofoil of Mars . Coastal terrainshave been observed with social system logical with water system rush in and then flowing back down to lower altitudes . Researchers have attributed these structures to different tsunamis that may have happened during times the climate had changed importantly .

The climate is a all important constituent in this discussion . Ancient Mars is expected to be very cold for many cause , admit the fact that the Sun emitted a lot less radiation syndrome back then than it does now . A long - go ocean seems very improbable in those freeze conditions , instead requiring warm and wet conditions to maintain . That enunciate , in this study , the researcher make a compelling case for the ocean ’s existence .

If the Lomonosov Crater ’s feature were indeed triggered by rushing water , it would advise that an ocean was indeed present and given how rare impacts of this size of it are , this ocean must have been there for a very long time .

[ H / T : The New York Times ]