The red planet is not all red. One of its craters is hiding strange green rocks

Perseverance detected the presence of volcanic rocks composed of large-sized olivine grains in the crater. Many beaches on Earth have a greenish appearance due to the presence of olivine, a mineral abundantly found in Earth’s mantle and involved in the formation of the gemstone peridot. The presence of olivine-rich rocks on Mars could reveal answers to questions like — Did Mars ever support life?

The green rocks suggest so many things

The researchers believe that volcanic rocks discovered on the red planet were formed about four billion years ago. Interestingly, the rocks have properties similar to that of igneous rocks that existed on Earth during its early days. In order to study the ancient environment of a planet, scientists need rock samples from the time the planet was formed.

For instance, “one of the reasons we don’t have a great understanding of where and when life first evolved on Earth is because those rocks are mostly gone, so it’s really hard to reconstruct what ancient environments on Earth were like,” said Dr. Briony Horgan, one of the authors and associate professor at Purdue University’s Department of Earth, Atmospheric, and Planetary Sciences.

Mars is believed to be 4.6 billion years old, and fortunately, in the form of the olivine-rich igneous rocks, Perseverance has spotted the location of the age-old lava samples required to study the planet’s ancient environment. Previously, some studies concerning Martian meteorites also hinted at the presence of olivine on the red planet.

However, the mineral was considered only limited to regions like Ganges Chasma and Nili Fossae. Until now, researchers were never sure about the presence of olivine in the Jezero crater. “Before the landing of Perseverance, the origin and lithology of Jezero crater’s floor were strongly debated, whether igneous (lava flows or pyroclastic) or sedimentary,” wrote the authors in their study.

There is a great possibility that by studying the data from the rover and possibly one day examining the rocks here on Earth, scientists could finally reveal if life ever existed on the red planet. Moreover, since the ancient volcanic rocks are as old as our solar system, they could also shed light on the genesis of life on Earth and on how we should proceed in our quest for signs of life on other planets.

Explaining this further, Professor Horgan notes, “The rocks Perseverance is roving over in Jezero have more or less just been sitting at the surface for billions of years, waiting for us to come look at them. That’s one of the reasons that Mars is an important laboratory for understanding the early solar system.”

The analysis of Perseverance's observations is published in the journals Science Advances and Science.