Mars is slowly ripping apart its biggest moon Phobos, new findings by NASA scientists showed.
According to the scientists at NASA’s Goddard Space Flight Center in Maryland, the red planet’s gravity is pulling Phobos, the bigger of its two moons, toward it by about 2 meters every hundred years.
Phobos orbits Mars at a distance of about 3700 miles which is the shortest distance between any planet and its moon in the solar system. The impact of the gravitational pull could be disastrous to the moon and scientists believe that Phobos will disappear in about 30 to 50 million years from now.
According to the new findings the long and shallow grooves found on Phobos are early signs of a structural failure that could eventually lead to its total collapse.
“We think that Phobos has already started to fail, and the first sign of this failure is the production of these grooves,” said Terry Hurford of NASA’s Goddard Space Flight Center in Greenbelt, Md.
The scientists earlier had believed that the fault lines on Phobos was the result of a cosmic collision that almost shattered the moon. The collision was so powerful that it created a huge crater on the moon and scientists earlier believed that the grooves on the moon also was formed due to the impact.
But new modeling by Hurford and colleagues supports the view that the grooves are more like “stretch marks” that occur when Phobos gets deformed by tidal forces.
The gravitational pull between Mars and Phobos produces these tidal forces. Earth and our moon pull on each other in the same way, producing tides in the oceans and making both planet and moon slightly egg-shaped rather than perfectly round, NASA said in a statement.
The recent research findings also reveal that the moon is more like a bundle of rubble that is held together by a thin outer surface.
“The funny thing about the result is that it shows Phobos has a kind of mildly cohesive outer fabric,” said Erik Asphaug of the School of Earth and Space Exploration at Arizona State University in Tempe and a co-investigator on the study. “This makes sense when you think about powdery materials in microgravity, but it’s quite non-intuitive.”
According to the scientists the outer surface of Phobos which is about 330 feet thick, behaves elastically and builds stress. And the tidal forces acting on the moon can produce enough stress to fail its weak crust.