Astro News Briefs: March 10–16

Yet More Moons for Jupiter

March 11, 2003 | Hot on the heels of last week's announcement, Scott Sheppard (University of Hawaii) has added to Jupiter's satellite tally yet again, having found four more, bringing the planet's moon count to 52. These latest moonlets were announced by the International Astronomical Union (IAU) on Circular number 8089. For now they carry the temporary designations S/2003 J9 through S/2003 J12. All are in retrograde orbits (traveling in the opposite direction as Jupiter's rotation); their revolution periods range from 533 to 767 days. The faintest one had a magnitude of 23.9, and all have estimated diameters of just 1 or 2 kilometers.

To view specifications of all known satellites, including Jupiter's newest moonlets, see SkyandTelescope.com's Guide to Planetary Satellites.