The first NEO discovered by PACS was (5496) 1973 NA, an Apollo asteroid with an exceptional orbital inclination of 68°, the most highly inclined minor planet known until 1999. In 1976, Eleanor Helin discovered 2062 Aten,[7] the first of a new class of asteroids called the Aten asteroids with small orbits that are never far from Earth's orbit. As a result, these objects have a particularly high probability of colliding with the Earth. In 1979, Helin discovered an Apollo-type asteroid, that they later identified with the comet 4015 Wilson–Harrington.[8] It was the first confirmation that a comet can evolve into an asteroid after it has degassed.[6]
^Gehrels, Tom, ed. (1994). Hazards due to comets and asteroids. Tucson: Univ. of Arizona Press. pp. 129–131, 137. ISBN9780816515059.
^Barnes-Svarney, Patricia (2003). Asteroid : earth destroyer or new frontier? (Paperback ed.). Cambridge, Mass.: Basic Books, a member of the Perseus Books Group. p. 246. ISBN9780738208855.