Discovery of Francisco

Francisco is a small irregular moon of Uranus, found in 2001 by an astronomical team led by Matthew Holman that was searching for faint outer satellites of the giant planets. It circles Uranus at a great distance on a retrograde orbit, running opposite to the planet's rotation, which is typical of bodies captured long ago rather than formed alongside the planet. Such moons are often thought to be fragments of larger captured objects broken up by collisions. In keeping with the convention for Uranus's satellites, it is named after a lord in Shakespeare's play The Tempest. It is far too faint to be seen without large telescopes and is known mainly from careful ground-based measurements of its motion.

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