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A celestial speck that astronomers thought was a meteoroid is in fact
Jupiter’s 17th moon—its smallest, and the first found for 26 years.
University of Arizona astronomers used the 36-inch telescope at Kitt Peak to
track the object for a month last year. They estimate that the object orbits
Jupiter once every two years at an average distance of 24 million kilometres.
The new moon may measure only 5 kilometres across, and it won’t get a permanent
name and number unless researchers spot it re-emerging from the Sun’s glare in
September.