SPACEWATCH® is the name of a group at the University of Arizona's Lunar and Planetary Laboratory founded by Prof. Tom Gehrels and Dr. Robert S. McMillan in 1980. Today, Spacewatch is led by Dr. Robert S. McMillan. The original goal of Spacewatch was to explore the various populations of small objects in the solar system, and study the statistics of asteroids and comets in order to investigate the dynamical evolution of the solar system. CCD scanning studies the Centaur, Trojan, Main-Belt, Trans-Neptunian, and Earth-approaching asteroid populations. Spacewatch also found potential targets for interplanetary spacecraft missions. Spacewatch currently focuses primarily on followup astrometry of such targets, and especially follows up objects that might present a hazard to the Earth.
CCD observations are conducted 24 nights each lunation with the Steward Observatory 0.9-meter Spacewatch telescope and the Spacewatch 1.8-m telescope, both on Kitt Peak. Emphasis today is on recovering faint solar system objects, especially Near Earth Asteroids which have been found to pose an impact hazard, such as the Virtual Impactors (VI's) and Potentially Hazardous Asteroids (PHA's). Other objects of interest include future Radar targets, possible targets of human exploration and objects discovered by the WISE and NeoWISE surveys which have valuable infrared estimates of their size. The 1.8-meter telescope allows us to observe objects more than 0.7 magnitudes fainter than the 0.9-meter telescope. To complement the deep penetration of the 1.8-m, we have put a mosaic of CCDs on the 0.9-m telescope. This permits us to cover sky at least six times faster than the pre-2002 system when in survey mode.
Spacewatch also uses other large telescopes such as the 4-meter Mayall telescope on Kitt Peak and the Steward Observatory 90 inch Bok Telescope on Kitt Peak to do systematic followup of Near Earth Asteroids such as virtual impactors, potentially hazardous asteroids, radar targets, possible spacecraft targets and objects discovered by the WISE and NeoWISE surveys.