Mars might have a ring like Saturn’s in 20 million years

Using the calculations gained from this process, they determined that the weakest parts of the moon will form a ring approximately 20 million years from today.

Eventually Phobos will either smash apart due to increasing tidal stresses caused by Mars’s gravitational pull or crash into the planet.

Combining observational data with a computer model to calculate the internal strength of Phobos the researchers found much is composed of weak materials. If the moon crashes into Mars, it would devastate both bodies, but even if Phobos experiences tidal breakup, a few of the larger pieces of debris could cause new craters on Mars. Phobos, the larger of the two, only has a mean radius of about 11 km, while Deimos, its smaller sister, is seven times smaller. “If you were standing on the surface of Mars, you could grab a lawn chair and watch Phobos shearing out and spreading into a big circle”, said Berkeley planetary scientist Benjamin Black to Nature.

If and when that happens, the debris from the moon’s failure could form rings around Mars, according to research published in Nature.

Over time Phobos is creeping inwards towards Mars at a couple of centimetres per year. If any larger pieces break off from Phobos, they will likely fall to the surface of Mars and cause impact craters.

“We predict that the initial density of a ring formed from the breakup of Phobos could rival or exceed the density of Saturn’s rings”, Black told Popular Science.

“Our analysis of the evolution of Phobos underscores the potential orbital and topographic consequences of the growth and self-destruction of other inwardly migrating moons – including those that met their demise early in our Solar System’s history”.

When the Martian moon disintegrates, it will become the first ring to form around a rocky planet.

Every century, gravity pushes Phobos 2 meters (6.6 feet) closer to Mars.

The moon rotates around Mars faster than the planet itself spins which might be a side effect of Phobos’ low density. Phobos’ death spiral will leave behind a ring system that is similar to Saturn’s famed rings.

The researchers added that a number of missions to Phobos have been proposed, and those spacecraft might be able to make measurements that will help test their prediction.