Asteroid in Jupiter's orbit goes its own way
Outside of its orderly inner system of major moons, Jupiter is haloed by dozens of minor moons that can loop millions of kilometers out into space in years-long orbits. These moons are thought to be objects that Jupiter has occasionally captured from all the various comets, Centaurs and asteroids that cross Jupiter's path.
But how such a capture could occur has always been a puzzle; studied as abstract masses, there's nothing that one planet and one asteroid can do together that would put the asteroid into orbit around the planet.
But it's also long been mathematically theorized that capture would be possible if the asteroid were to split at least once during a close encounter with Jupiter. One piece could carry away most of the asteroid's kinetic energy into solar orbit, leaving other piece(s) moving slowly enough to fall into closed orbits around Jupiter.
Some of the outer moons are suggestive of such a thing, because they fall into families with similar orbits and appearances. The Carme Group for example, are over a dozen objects with similar reflection spectra occupying energetically similar orbits, apparently all born from the breakup of a single D-class asteroid sometime in the last million years or so.
Another oddity of the Carme Group is they are all retrograde, moving around Jupiter in reverse of the usual direction.
And now here is Asteroid 2015 BZ509, an object with an unusual retrograde orbit closely gravitationally controlled by Jupiter for the last million years or so. Could 2015 BZ509 be the "escape object" from the formation of the Carme Group -- the split fragment that escaped with most of the parent object's kinetic energy., leaving the rest of the shards stuck in Jupiter orbit?
The clue would be in its reflectance spectra. All the Carme Group moons share a peculiar reddish hue. If 2015 BZ509 shares their coloring it wouldn't be conclusive evidence, but it would be whatcha call "suggestive" of a link -- worth spending a lot more money to investigate.