Przy okazji innego badania ilość znanych księżyców Jowisza zwiększyła się o 12.
Przyglądając się bliżej pozostałym jowiszowym planetom też pewnie da się jakieś drobiazgi księżycowe wykryć.
Jupiter's moon count reaches 79, including tiny 'oddball'July 17, 2018, Carnegie Institution for Science
(...) Nine of the new moons are part of a distant outer swarm of moons that orbit it in the retrograde, or opposite direction of Jupiter's spin rotation. These distant retrograde moons are grouped into at least three distinct orbital groupings and are thought to be the remnants of three once-larger parent bodies that broke apart during collisions with asteroids, comets, or other moons. The newly discovered retrograde moons take about two years to orbit Jupiter.
Two of the new discoveries are part of a closer, inner group of moons that orbit in the prograde, or same direction as the planet's rotation. These inner prograde moons all have similar orbital distances and angles of inclinations around Jupiter and so are thought to also be fragments of a larger moon that was broken apart. These two newly discovered moons take a little less than a year to travel around Jupiter.
"Our other discovery is a real oddball and has an orbit like no other known Jovian moon," Sheppard explained. "It's also likely Jupiter's smallest known moon, being less than one kilometer in diameter".
This new "oddball" moon is more distant and more inclined than the prograde group of moons and takes about one and a half years to orbit Jupiter. So, unlike the closer-in prograde group of moons, this new oddball prograde moon has an orbit that crosses the outer retrograde moons.
As a result, head-on collisions are much more likely to occur between the "oddball" prograde and the retrograde moons, which are moving in opposite directions.
"This is an unstable situation," said Sheppard. "Head-on collisions would quickly break apart and grind the objects down to dust." (...)
https://phys.org/news/2018-07-jupiter-moon-tiny-oddball.html