3753 Cruithne It was not until 1997 that its unusual orbit was determined by Paul Wiegert and Kimmo Innanen, working at York University in Toronto, and Seppo Mikkola, working at the University of Turku in Finland. Cruithne is approximately in diameter, and its closest approach to Earth is , approximately thirty times the separation between Earth and the Moon. From 1994 through 2015, Cruithne made its annual closest approach to Earth every November. Although Cruithne's orbit is not thought to be stable over the long term, calculations by Wiegert and Innanen showed that it has probably been synchronized with Earth's orbit for
Near Earth Object Surveillance Satellite three missions. The spacecraft will demonstrate the utility of the "Multi-Mission Microsatellite Bus" (MMMB) as part of the CSA's efforts to develop an affordable multi-mission bus. "Near Earth Space Surveillance" (NESS), led by Principal Investigator Alan Hildebrand of the University of Calgary, will use NEOSSat to search for and track near-Earth asteroids inside Earth's orbit around the Sun, including asteroids in the Aten and Atira classes. These asteroids are particularly difficult to detect from the surface of the Earth, as they are usually positioned in the daylit or twilit sky, when background light from the Sun makes such faint objects