They say it's 5-10x Jupiter's mass. The brown dwarf range is 13-80x Jupiter's mass, and within that range stars can fuse deuterium -- so that rogue planet is on its way to becoming the smallest kind of star.
...It just needs to absorb about five more Jupiter masses, so roughly (9.5 * 10^27) kg. At six billion tons per second, if it can keep it going, that'll take 31.6M years. Not a lot of time, on cosmic timescales.
So can it, uh, become heavy enough to ignite the gas it collected?
They say it's 5-10x Jupiter's mass. The brown dwarf range is 13-80x Jupiter's mass, and within that range stars can fuse deuterium -- so that rogue planet is on its way to becoming the smallest kind of star.
...It just needs to absorb about five more Jupiter masses, so roughly (9.5 * 10^27) kg. At six billion tons per second, if it can keep it going, that'll take 31.6M years. Not a lot of time, on cosmic timescales.