Summary
PA (p.a.) Abbreviation for ➤ position angle.
Paaliaq A small outer moon of Saturn, in a very elliptical orbit. It was discovered in 2000 and is about 19 km (12 miles) across.
2 Pallas A large asteroid discovered by Heinrich W. M. Olbers in 1802. With a diameter of 533 km (331 miles), it is the second largest asteroid. It is of the carbonaceous type, similar to the largest asteroid, ➤ Ceres. Its orbit is at the unusually steep inclination of 35° to the plane of the solar system.
Pallene A small moon of Saturn discovered in 2004 by the ➤ Cassini team. It orbits Saturn at a distance of 211 000 km (131 000 miles) between Mimas and Enceladus.
Palomar Observatory The observatory on Palomar Mountain in California where the 5-m (200-inch) ➤ Hale Telescope is sited. It is owned and operated by the California Institute of Technology (Caltech). The other principal instruments at the observatory are the 1.2-m (48-inch) Oschin Telescope (a ➤ Schmidt camera), a 46-cm (18-inch) Schmidt camera and the 1.5-m (60-inch) reflector owned jointly by Caltech and the Carnegie Institution of Washington.
Pan A small moon of Saturn orbiting in the ➤ Encke Division in the planet's ring system at a distance of 133 583 km (83 005 miles) from Saturn. It was found by Mark R. Showalter in 1990 from studies of images taken by the spacecraft ➤ Voyager 1 and ➤ Voyager 2.
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- Cambridge Illustrated Dictionary of Astronomy , pp. 257 - 282Publisher: Cambridge University PressPrint publication year: 2007