I have a space question. I know about the Roche limit but is there an upper limit to how big a ring can get compared to its planet?
Asked by Dan
Of course there are limits, the Universe is all about limits! But they’re not as strict as one would think.
We found an object in 2012, J1407b, with a ring system 200 million kilometres in diameter. If the rings were centred on Earth they would cover the inner solar system all the way to the orbit of Mercury on the opposite side of the Sun. The media quickly dubbed the object Super-Saturn, and the Ring system seems to have the same characteristics: a proportional mass, resonance gaps, shepherd moons. But the system is very young (16 million years, a baby in cosmic term) and the object is not exactly a planet, rather a brown dwarf. So, what we see as a Ring system could be the beginning of a system of moons, rather than a stable ring.
But what about spatial limits? Depending where the material for the ring is coming from, the limit could be given by the Roche limit or simply by the position of the first ...