A Brown University research sheds light on the origin of the peculiar markings of Mars' Phobos, arguably the oddest yet most interesting moon there is.

A far cry from all other usually perfect-shaped moons is Phobos that is not just distinctive for its shape, but also because of the grooves and craters it possesses. It has gained quite the traction from researchers and scientists who are wondering how these indentations came about.

Stickney Crater

While other moons also have dents and scratches, Phobos is especially notable because it is full of these, which is why it is understandable that it easily piqued anyone's curiosity. One of its most eye-catching features is its Stickney crater, a hole that is 9 kilometer in diameter which makes it hard to miss.

The Stickney crater was formed some 150 years ago when a massive rock hit Phobos. Surrounding this unique and unmissable site are grooves seemingly extending from the impact location.

According to a research published in Planetary and Space Science, the rolling boulders, which were a result of the Stickney impact, may have been the reason behind the grooves. To prove this, the researchers simulated how massive rocks had rolled over the moon from the big crater, and that's how they concluded that the stones from that event created the grooves.

Lead researcher Ken Ramsley, who was surprised of what came out of the experiment, believes that their efforts are a big help toward determining other possible explanations of the grooves. He narrated that initially, the team had no expectations of what will be the outcome of the study.

The computer models also gave out an explanation on why other grooves aren't directly aligned with the huge impact site. This was allegedly a result of Phobos' size and weak gravity that caused boulders from Stickney to continuously roll all the way around the moon, which also explains why there are other overlapping grooves.

"It's like a ski jump. The boulders keep going but suddenly there's no ground under them. They end up doing this suborbital flight over this zone," Ramsley said of the parts of Phobos that had no grooves.

'Plausible' Explanation

All these may have happened in just a span of 12 hours, Ramsley explained. However, it is worth noting that the study is just a possible reason and not the definitive answer to the problem, with the researchers deeming the findings as "plausible."

NASA first saw the grooves in the 70s. Since then, a lot of the same research explained the relationship between the Stickney crater and the patterns.