Mars' moon Phobos is falling apart, and it is slowly getting deformed due to gravity's tidal forces.
Phobos, the larger of Mars' two moons, orbits some 6,000 km from its parent planet, meaning it is the closest moon to Mars. Now, a new study is claiming that this close distance, that grows closer at a rate of 2 meters, or 6.6 feet every 100 years, is the reason that it's slowly breaking apart, according to Fox News Latino.
The new research on Phobos was presented during the annual American Astronomical Society's Division for Planetary Sciences meeting, held at National Harbor, Maryland Tuesday.
Researchers have found long shallow grooves, appearing to be stress fractures, on Phobos' surface,
It had been previously thought by scientists that these grooves are fractures caused by an asteroid that crashed on it, nearly destroying it. Scientists call the resulting crack impact a Stickney crater, a basin measuring 6 miles, nearly half the size of Phobos.
The cracks were later found to have formed outside the Stickney crater in a later analysis. Scientists then came up with a new theory saying that the grooves resulted from Mars' debris smashing onto Phobos, which orbits 5,800 miles above Mars.
Meanwhile, the new study on Phobos conducted by Hurford and his colleagues posits another reason as to how the moon acquired the grooves and why it is slowly deteriorating.
Using new computer models, the new study's researchers show evidence that the grooves are akin to stretch marks. This means they are caused by the tidal forces from Mars' gravitational tug on Phobos.
Because Mars' pull is too much for Phobos, it is moving closer to Mars at three- to six feet per century. This means it would take Mars around 30 to 50 million years before crashing onto Phobos, Planetary Scientist Terry Hurford at NASA's Goddard Space Flight Center in Greenbelt, Maryland, told Discovery News.
"We think the grooves are signs that this body is starting to break apart tidally and that these are the first evidence of the tidal deformations of Phobos," Hurford said in a statement.
"Eventually, Phobos will be ripped apart before it reaches Mars' surface," he added.
Scientists now believe that the tidal force is the same force causing Earth's ocean tides, as well as the slight egg shape of our moon. They also believe that Phobos' interior is made up entirely of rubble and that Phobos is simply held together by dust and rock measuring only 100 meters.
According to Discovery News, numerous questions still remain about Phobos and Mars' other moon Deimos, both believed to be captured asteroids. NASA and other agencies are reportedly conducting studies on Phobos to detect possible missions there, which could eventually lead to human missions on Mars.
Check out photos of Mars' moon Phobos below.
Check out a related video below.