Planet X disproved Harrington died in January 1993, without having found Planet X.Croswell (1997), p. 66. Six months before, 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.Littman (1990), p. 204. Today, most astronomers agree that Planet X, as Lowell defined it, does not exist.
planet x disproved harrington died in january 1993 without having found planet xcroswell (1997) p 66 six months before e myles standish had used data from voyager 2'''s 1989 flyby of neptune which had revised the planet's total mass downward by 05%—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 systemlittman (1990) p 204 today most astronomers agree that planet x as lowell defined it does not exist