Phobos may be falling, according to NASA. Slowly. As in at a rate of 6.6 feet per 100 years. So, within the course of the next 30-60 million years, Mars may have rings like Saturn. Or it may just see the collision of its moon with its surface.
Phobos is one of Mars’ 2 moons. Measuring in at 22 kilometers, the moon isn’t large on the astronomical scale but that doesn’t mean it isn’t very interesting. The moon orbits in less than 8 hours, meaning you can watch it go from one horizon to the next in about 4 hours if you were standing on the surface of Mars!
The moon is also oddly shaped, bearing a large impact crater that deforms the moon into an oblong form. Phobos bares several fissures and rippled geological patterns upon its surface. Long thought to be impact fissures due to the deforming crater on it’s surface, scientists now believe these may actually be “stretch marks” as the moon is torn apart by Mars’ gravitational fields.
“We think that Phobos has already started to fail, and the first sign of this failure is the production of these grooves,” says Terry Hurford of NASA’s Goddard Space Flight Center in Maryland.
Phobos was once thought to be hollow, given it’s fast and low orbit about Mars. However, the moon may just be very “loose” on the geological scale. It’s crust may be surrounding a very poorly clumped material that is breaking up the closer it gets to Mars. This would explain the building fissures on the surface and the peculiar surface topology of the moon.
Not only is the moon slowly falling, but it is also host to a number of fun conspiracy theories. It was once thought to be hollow by the Russian Astrophysicist Iosif Samuilovich Shklovsky during the 1960’s. Also, the 2 Phobos missions launched by Russia disappeared under mysterious circumstances. Peculiar thermal imaging have led people to claim everything from hidden subterranean cities to classified military outposts! Although most can be dismissed with scientific evidence, Phobos is still subject of lots of scientific intrigue. Perhaps this doomed, dystopian heritage is fitting to the moon named after the Greek god of Horror Personified.