Robert Sutton Harrington
Robert Sutton Harrington (October 21, 1942 – January 23, 1993) was an American astronomer who worked at the United States Naval Observatory (USNO). Harrington was born near Newport News, Virginia. His father was an archaeologist. He was married to Betty-Jean Maycock in 1976, with two daughters, Amy and Ann.
Harrington worked at the USNO. Another astronomer there, James W. Christy, consulted with him after discovering bulges in the images of Pluto, which turned out to be Pluto's satellite Charon. For this reason, some consider Harrington to be a co-discoverer of Charon, although Christy usually gets sole credit. By the laws of physics, it is easy to determine the mass of a binary system based on its orbital period, so Harrington was the first to calculate the mass of the Pluto-Charon system, which was lower than even the lowest previous estimates of Pluto's mass.
Harrington became a believer in the existence of a Planet X beyond Pluto and undertook searches for it, with positive results coming from the IRAS probe in 1983. Harrington collaborated initially with T. C. (Tom) Van Flandern.
Harrington's version of Planet X disproved six months before he died
Six months before Harrington's death, E. Myles Standish had used data from Voyager 2's 1989 flyby of Neptune, which had revised the planet's total mass downward by 0.5%—an amount comparable to the mass of Mars—to recalculate its gravitational effect on Uranus. When Neptune's newly determined mass was used in the Jet Propulsion Laboratory Developmental Ephemeris (JPL DE), the supposed discrepancies in the Uranian orbit, and with them the need for a Planet X, vanished. There are no discrepancies in the trajectories of any space probes such as Pioneer 10, Pioneer 11, Voyager 1, and Voyager 2 that can be attributed to the gravitational pull of a large undiscovered object in the outer Solar System. Although most astronomers agree that Planet X, as Lowell defined it, does not exist, as of January 2016 there is speculation concerning Planet Nine.
- Betz, Eric (2015-06-09). "An interview with Jim Christy: How "defective" images revealed Pluto as a double planet". Astronomy.com. Retrieved 2016-06-26.
- Croswell (1997), p. 66.
- Myles Standish (1992-07-16). "Planet X – No dynamical evidence in the optical observations". Astronomical Journal. 105 (5): 200–2006. Bibcode:1993AJ....105.2000S. doi:10.1086/116575.
- Tom Standage (2000). The Neptune File: A Story of Astronomical Rivalry and the Pioneers of Planet Hunting. New York: Walker. p. 188. ISBN 978-0-8027-1363-6.
- Littmann (1990), p. 204.
- Tom Standage (2000). The Neptune File. Penguin. p. 168. ISBN 0-8027-1363-7.