Mars is not the only interesting body in its region as astronomers found out what's causing the mysterious groves on one of the planet's moon, Phobos. Based on NASA's images, there were grooves or "stretch marks" on the surface of Phobos that science has failed to explain until today.

Astronomers first discovered the pattern that resembles craters on the surface of Phobos. Since then, experts have argued as to what could have caused the craters and the strange landscape on the moon. For years, different theories have emerged, but it is not until today that a breakthrough discovery finally settled the debate.

Phobos will likely be ripped apart by Mars' tidal force, according to a report. But despite the obvious damage to the moon, the chain of craters remained a mystery to astronomers for a very long time.

The Martian moon Phobos is one of the two moons of the planet and is also the nearest to Mars. It is believed to be composed of a combination of rubble unlike other bodies which are made up of solid mass. To understand how the craters were formed, astronomers used simulations.

Based on their findings, it turned out that impact by asteroids and comets may have caused the uneven terrain. This explains the formation of chains of craters on the surface of the moon.

"All this dirt is kicked up, and it falls nearby very ballistically, creating dimples in the surface," Michael Nayak, co-author of the study said in a statement. "Imagine a golf ball rolling along the sand and it suddenly bounces, leaving a dimple here and a dimple there until at some point it just peters out," Nayak added.

During the Viking's mission by NASA in the 1970s, the first images of Phobos were captured. Since then, the "stretch marks" on the surface of Phobos have gained the interest of astronomers trying to study and explain the terrain.

Succeeding data from NASA's Mars Global Surveyor and the European Space Agency discovered that there were more grooves in Phobos. However, they don't appear to be tidal grooves as what they were initially thought to be.

The study simulated the impact at Gildrig, a 2.6-kilometer crater near the moon's north pole, and to the astronomers' surprise, the result is almost the same as the real-life chain of craters on the Martian moon, according to a report by Cosmos Magazine.

The astronomers that led the study are confident that their simulation model can explain the mysterious craters on Phobos. And given Phobo's odd orbit and low mass, it may be the only place to find these crater chains.