Mars Could One Day Have a Ring Like Saturn
Earlier in the month, we wrote about how the structural failure of Mars’ innermost moon, Phobos, may lead to its eventual destruction. Now research published in Nature Geoscience is suggesting that when Mars loses its largest moon, it could possibly gain a ring system similar to the one circling Saturn [PDF].
The chances of the moon Phobos disintegrating into a ring of debris around the red planet hinge on the satellite’s strength. The force of Mars' gravity is currently dragging the largest of its two moons towards it at a rate of 6.6 feet every 100 years. At that speed, the two bodies are set to collide in 30 to 50 million years or so, but some experts believe the moon won’t last that long. Phobos, which is likely composed of porous, heavily damaged rock, may instead be slowly taken apart by the planet’s gravity over the course of 20 to 40 million years. If that's the case, Mars will end up with a nifty new ring system made from the moon’s remains.
The ring would initially be similar to Saturn's rings in terms of density, but as Mars continued to pull in debris from its orbit, the ring would eventually thin out. (Such rings in our solar system are generally composed of space debris and, possibly, destroyed moons.) As for what a Martian ring would look like, it all depends on your point of view. From the surface of Mars, you'd see a curved ring that looked either light (if the ring was reflecting extra light towards you) or dark (if you were standing in the ring's shadow). Either view could be dramatic for any Earthlings who might visit Mars in the future. They’ll just need to make sure they set up camp far away from the equator, as incoming ring particles could prove to be problematic.
[h/t: Scientific American]