Right now on Mars, there are two rovers: Opportunity and Curiosity. The first one is sleeping while the dust storm still engulfed the red planet, while Curiosity keeps a regular schedule of selfies and analyzing the soil. So far so good, NASA just discovered a massive underground lake under the Martian surface. But all over the surface, there’s dirt and never-ending dust. Where did it come from?
Scientists found the source! On Earth, dust is lifted from the rocks by natural forces like wind, water, volcanic activity, but there is no water on the surface or too much wind to form such a fine powder.
The Medusae Fossae Formation
Johns Hopkins University’s planetary scientist Lujendra Ojha has analyzed and found a region on the planet that could be the one behind all this dust. They estimated that there could be 3 trillion kilograms of dust produced every year. Planetary geophysicist Kevin Lewis is part of Ojha’s team, explaining that:
“Mars wouldn’t be nearly this dusty if it wasn’t for this one enormous deposit that is gradually eroding over time and polluting the planet.”
But the 1,000-kilometre-long formation was discovered back in the 60s, and only recently scientists realized that it has volcanic origins, meaning that this is the largest volcanic deposit ever recorded in the Solar System. The scientists called it Medusae Fossae Formation and a long time ago; it was a lot bigger. However, it is vulnerable to erosion, and it now has remained a ghost of what it was in the past.
The team analyzing this formation have reported their finding in Nature Communications, claiming that this region is the culprit behind all dust on the Red Planet. The proof is that the Medusae Fossae Formation has dust with a chemical composition that matched the composition of other dust samples taken on the planet by the NASA spacecraft Mars Odyssey, explained Ojha:
“Dust everywhere on the planet is enriched in sulfur and chlorine and it has this very distinct sulfur-to-chlorine ratio.”
Considering that, according to the team’s analysis, the reduction of volcanic rock dates back to about 3 billion years, it’s only obvious that the Martian dust that now coats the surface (reaching a thickness from 2 to 12 meters) comes from that region.
Rex Austinwas born and raised in Thunder Bay Ontario on the shores of Lake Superior. Apart from running his own podcast (Ice Fishing And Other “Cool” Things), he spends his time canoeing and backpacking in Northern Ontario.. As a journalist Rex has published stories for Global News (Thunder Bay) we well as Buzz Feed and Joystiq. As a contributor to Great Lakes Ledger, Rex most covers science and health stories. Contact Rexhere