NASA’s Perseverance rover made the discovery. It’s true: there was once lava in an ancient lake on Mars. The bedrock on which the rover is moving had volcanic lava in the past. Where was the news of the discovery made? At the American Geophysical Union Fall Meeting in New Orleans. Traces of lava from Mars are a fact.
Long search
The scientists in charge of the mission maintain that the finding is “completely unexpected.” They thought the rocks the rover had investigated were of sedimentary origin. The rocks themselves show organic molecules. The truth is that scientists had long had doubts about this. They were not convinced that the rocks in the crater were sedimentary.
“I was already beginning to despair that we would never find the answer.” Says a relieved Ken Farley, one of the scientists on the Perseverance project. He works at the California Institute of Technology in Pasadena, California.
At last, Perseverance managed to drill through one of the rocks with its robotic arm. “The crystals inside the rock were conclusive proof.” This convinced Farley.
In November, Perseverance used the same instruments to study another rock. And concluded that it contained olivine crystals surrounded by pyroxene crystals. In other words, rocks from lava flows.
A decisive test
“A good student of geology will tell you what happened. Such a texture indicates that the rock formed when crystals grew and settled in a slowly cooling magma. e.g.? A thick lava flow. A lava lake or a magma chamber,” Farley said.
Now, the team has another goal. They will find out if the lava traces on Mars are due to a lava lake that cooled. Or if they originated in an underground lava chamber that was exposed by erosion.
The more we look, the more it resembles our planet’s past. Sooner or later Mars will be our future too.
