Scientists say Mars may just be too small to support life

Numerous data from Mars suggest the proximity the red world was once much more watery, like Earth. Today, of course, there doesn’t appear to be any liquid water on the planet’s surface, and scientists have suggested several possible explanations for the notorious Martian aridity.

It’s possible that a period of volcanic activity altered the climate, some say, while another popular theory accuses Mars’s lack of a strong magnetic field to have allowed its atmosphere – and ultimately all of its water. – to simply drift in space. A new study published Monday in the Proceedings of the National Academy of Sciences puts forward a more basic reason for the planet’s persistent thirst: It is just too small.

“The fate of Mars was decided from the start,” University of Washington professor of planetary science Kun Wang, lead author of the study, said in a statement. “There is probably a threshold on the size requirements of rocky planets to hold enough water to allow habitability and plate tectonics, with a mass exceeding that of Mars.”

Wang and his colleagues studied the amount of potassium isotopes present in Martian meteorites, using the element as a kind of tracer for more volatile molecules, including water. Researchers found that during its formation, Mars lost more water and other volatile substances than its larger neighbor, Earth, while retaining more vital molecules than smaller, drier bodies like the moon or the asteroid Vesta.

“This study highlights that there is a very limited size range for planets to have just enough but not too much water to develop a habitable surface environment,” said study co-author Klaus Mezger of the Center. Switzerland for space and livability from the University of Bern. . “These results will guide astronomers in their search for habitable exoplanets in other solar systems.”

This could mean that, as we continue to search the skies for an answer to the crucial question of whether we are alone, it might be wise to start blowing up some of the galaxy’s most puny planets. The good news is these were going to be harder to spot anyway. Super-Earths here we are.