An article published in the journal “Nature” presents a study that describes two possible mega-tsunamis that shook the surface of the planet Mars more than three billion years ago. According to a team led by J. Alexis Palmero Rodriguez of the Planetary Science Institute two meteorites hit Mars a few million years from each other but with similar effects. Perhaps at that time there was an ocean of liquid water and the impacts raised waves up to 120 meters (almost 400 fett) which engulfed large areas of the mainland.

For several years we know that when it was young Mars was much more like Earth and slowly the geological studies of the Red Planet are showing the characteristics it had more than three billion years ago. According to many researchers, at the time Mars was a smaller version of the Earth with an atmosphere and liquid water on the surface. At some point something changed and the planet became the one we know today.

One of the problems in the hypothesis of the ancient ocean on Mars is the fact that so far the geological studies haven’t identified shorelines with constant height. According to this new research the shorelines of the Martian oceans are characterized by sediments distributed by tsunami deposits. At that time, the planet may have been periodically hit by large meteorites that generated serious consequences, especially two of them.

The researchers looked at pictures taken by various space probes in orbit around Mars to find traces of these ancient events. The geological formations that according to J. Alexis Palmero Rodriguez and his team are still showing the effects of two different mega-tsunamis exist in the area where Arabia Terra meets Chryse Planitia.

According to the researchers, after the impact that caused the first mega-tsunami the Mars oceans’ levels withdrew to form a secondary shoreline. The climate cooled down considerably and evidence is visible in the morphology of the deposits derived from it. They’re made primarily of large boulders and when the big wave withdrew the undertow generated gigantic channels.

The second mega-tsunami, which occurred a few million years later, created ice lobes. At that time, the climate was much colder so the water that was pushed out of the ocean partly froze mixing with sand and soil and leaving lobe-shaped debris. These are also the materials that could be subject to geological research but also regarding possible traces of life. That’s because the water could be salty enough to keep at least part of it in its liquid state.

The next step will be to look for evidence of tsunami in other areas of Mars but also on Earth to make useful comparisons and better understand how these phenomena can happen and their consequences. New studies conducted using Mars space probes and rovers will keep on improving our geological knowledge of the Red Planet and its history.