Search results
Results from the WOW.Com Content Network
Only one of them – Pluto – has been observed in enough detail to verify that its current shape fits what would be expected from hydrostatic equilibrium. [53] Ceres is close to equilibrium, but some gravitational anomalies remain unexplained. [54] Eris is generally assumed to be a dwarf planet because it is more massive than Pluto.
Since 2008, there have been five dwarf planets recognized by the IAU, although only Pluto has actually been confirmed to be in hydrostatic equilibrium [25] (Ceres is close to equilibrium, though some anomalies remain unexplained). [26] Ceres orbits in the asteroid belt, between Mars and Jupiter. The others all orbit beyond Neptune.
Pluto: 1930 2006 Dwarf planet: Following its discovery in 1930, Pluto was considered the ninth planet. Numerous scientific discoveries in the 1990s and early 2000s placed doubt on this classification, and after the discovery of Eris, which was thought to be larger than Pluto, the International Astronomical Union met to determine a definition of ...
Eris has been measured at 2,326 ± 12 kilometres (1,445 ± 7 mi) in diameter; [12] its mass is 0.28% that of the Earth and 27% greater than that of Pluto, [23] [24] although Pluto is slightly larger by volume. [25] Both Eris and Pluto have a surface area that is comparable to that of Russia or South America. Eris has one large known moon, Dysnomia.
Like Pluto, its orbit is highly eccentric, with a perihelion of 38.2 AU (roughly Pluto's distance from the Sun) and an aphelion of 97.6 AU, and steeply inclined to the ecliptic plane at an angle of 44°. [220] Gonggong (33.8–101.2 AU) is a dwarf planet in a comparable orbit to Eris, except that it is in a 3:10 resonance with Neptune.
This new class of objects, termed plutoids, would include Pluto, Eris and any other trans-Neptunian dwarf planets, but excluded Ceres. The IAU decided that those TNOs with an absolute magnitude brighter than +1 would be named by a joint commissions of the planetary and minor-planet naming committees, under the assumption that they were likely ...
Pluto (minor-planet designation: 134340 Pluto) is a dwarf planet in the Kuiper belt, a ring of bodies beyond the orbit of Neptune. It is the ninth-largest and tenth-most-massive known object to directly orbit the Sun. It is the largest known trans-Neptunian object by volume, by a small margin, but is less massive than Eris.
It can easily be trimmed back to reflect Pluto's demotion to dwarf planet. "My Very Elegant Mother Just Sat Upon Nine Porcupines" [1] "Mary's violet eyes make Johnnie stay up nights pondering" [2] With the IAU's 2006 definition of planet which reclassified Pluto as a dwarf planet, along with Ceres and Eris, these mnemonics became obsolete.