If you ranked the planets of the solar system by the number of their moons, Jupiter would reign.
Jupiter, the biggest planet in our cosmic neighborhood—and perhaps the most photogenic one—is circled by a surfeit of objects. Some of them are truly massive, veritable worlds of their own, like icy Europa, and volcanic Io, and sparkling Ganymede. Some are tiny things, measuring just several miles across. And even today, when our solar system feels downright familiar in comparison with the darkness beyond its edges, some of Jupiter’s moons are still being discovered.
The International Astronomical Union’s Minor Planet Center, the organization in charge of confirming discoveries of new objects in the solar system, on Tuesday added 10 new moons to Jupiter’s roster, bolstering its place at the top of the most-moons list.
The moons were discovered by Scott Sheppard, an astronomer at the Carnegie Institution for Science, in the spring of last year. Sheppard found them with the help of a ground-based telescope in Chile that had recently received an upgrade: a camera made for scanning the night sky for very faint objects. Sheppard was looking for Planet Nine, the planet some astronomers believe lurks somewhere at the edge of our solar system, jostling the orbits of other objects in strange ways. As the telescope gazed in the darkness way beyond Pluto, it ended up catching something much closer: a flurry of glinting, tiny objects near Jupiter, the smallest of which was about half a mile wide.