It turns out that Mars may have become more likely to support life due to a massive bombardment that occurred four billion years ago. As asteroids and comets as large as West Virginia crashed into the Red Planet, they actually changed the environment of the planet.
Scientists have long known that there was once running water on Mars. This is largely due to evidence of river valleys, deltas and parts of lake beds that can be found on the planet. Today, though, Mars is a relatively barren and cold place.
In this latest study, though, researchers believe that they may have found what may have helped warm up the planet a bit more.
A lot of the action on Mars occurred during a period known as the Late Heavy Bombardment. This occurred about 3.9 billion years ago when the developing solar system was a shooting gallery of comets, asteroids, moons and planets.
"This study shows the ancient bombardment of Mars by comets and asteroids would have been greatly beneficial to life there, if life was present," said Stephen Mojzsis, a professor at the University of Colorado Boulder. "But up to now we have no convincing evidence life ever existed there, so we don't know if early Mars was a crucible of life or a haven for life."
In order to learn a bit more, the researchers used the Janus supercomputer cluster. More specifically, they looked at temperatures beneath individual craters to take a closer look at the heating, cooling and impacts on Mars from different angles and velocities.
So what did they find? Individual asteroid collisions would have lasted only a few million years before Mars then defaulted to today's cold and inhospitable climate. In other words, Mars had brief stints of a climate that may have been able to support life and possibly caused flowing water on the planet.
"Studies of Mars provide us with valuable information about our own place in the solar system," Mojzsis said. "Our next steps are to model similar bombardment on Mercury and Venus to better understand the evolution of the inner solar system and apply that knowledge to studies of planets around other stars."
The findings were published in the journal Earth and Planetary Science Letters.
