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Brett J. Gladman (Observatoire de Nice, FRANCE), Philip D. Nicholson, Joseph A. Burns (Dept. of Astronomy, Cornell University), JJ Kavelaars (Dept. of Physics \& Astronomy, McMaster University, CANADA)
We report the discovery of the first 2 irregular satellites of Uranus, now officially designated Uranus XVI and XVII. The discovery was initially announced Oct.~31 1997 after the objects were confirmed to be bound to Uranus, although the original discovery images were taken in early September 1997. Initial photometric results indicate that the moons appear red in color, and that they have radii of 30 and 60 km. They are the faintest moons yet discovered, at apparent magnitudes of R=20.4 and 21.9. The moons were roughly 6-7 arcminutes from that planet at discovery. After Uranus moved behind the Sun during winter 1997-98, large-field CCD observations from the southern hemisphere were arranged for March and April 1998 to attempt to recover the two new moons after the planet re-emerged into the morning sky; the orbits were sufficiently imprecise that this was of great importance. The successful recoveries, along with archival observations obtained from photgraphic plates were sufficient to provide very accurate planetocentric orbits. The moons are both retrograde (with respect to the orbital plane of Uranus), with inclinations of about 140 and 150 degrees. Issues related to the origin of these two moons and to the existence of additional irregular moons will be discussed.