50 years ago, scientists found a new moon orbiting Jupiter

Jupiter’s new moon — Science News, November 2, 1974

Jupiter’s tentatively identified 13th moon, discovered in September by California Institute of Technology astronomer Charles Kowal, now appears almost certain to be the real thing.… So far known only as J-XIII, the object appears to orbit the planet in the same direction as its rotation.

Update

J-XIII, now known as Leda, was just the beginning. Scientists now recognize a bounteous 95 moons of Jupiter. And thousands of smaller objects orbit the planet, too. A few moons were uncovered by the Voyager spacecraft in 1979. In recent years, telescope surveys have unveiled a dozen moons at a time (SN: 7/17/18). Detailed studies of the largest moons have revealed Io’s lava lakes and Europa’s icy surface (SN: 4/18/24; SN: 12/15/22). NASA’s Europa Clipper mission is slated to arrive at the icy moon in 2030 to search for signs of habitability (SN: 10/15/24). And the European Space Agency’s Juice mission will scrutinize Europa, Callisto and Ganymede beginning in 2031 (SN: 12/20/23).