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Armagh Observatory, 24 July 2000:
The Minor Planet Center at the Smithsonian Astrophysical Observatory, Cambridge, Massachusetts, USA, has announced the discovery of a new moon of Jupiter, bringing to 17 the number of known satellites orbiting the giant planet.

At the suggestion of James Scotti, a member of the Spacewatch project of the University of Arizona and a part-time research student at Armagh Observatory, the sky around Jupiter was scanned electronically for a few nights in October last year. At that time, Jupiter was about 370 million miles from Earth, just about as close as it ever gets, and therefore a good time to search for any faint satellites.

Initially, the satellite was thought to be an asteroid and so it was given the designation 1999 UX18. It soon became apparent that the object was moving in an unusual manner for an asteroid, and that it was in fact moving around Jupiter.

This is the first satellite of Jupiter to be discovered in more than 25 years, the last being in 1974. The moon is about 3 miles across and orbits Jupiter at a distance of about 17 million miles in a 'month' of 774 Earth days.

FOR FURTHER INFORMATION CONTACT: John McFarland at the Armagh Observatory. Tel.: 028-3752-2928.

Last Revised: 10th August 2000
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