Search results
Results From The WOW.Com Content Network
A dwarf planet is a small planetary-mass object that is in direct orbit around the Sun, massive enough to be gravitationally rounded, but insufficient to achieve orbital dominance like the eight classical planets of the Solar System.
For example, if a TNO is incorrectly assumed to have a mass of 3.59 × 10 20 kg based on a radius of 350 km with a density of 2 g/cm 3 but is later discovered to have a radius of only 175 km with a density of 0.5 g/cm 3, its true mass would be only 1.12 × 10 19 kg.
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.
The radii of these objects range over three orders of magnitude, from planetary-mass objects like dwarf planets and some moons to the planets and the Sun. This list does not include small Solar System bodies , but it does include a sample of possible planetary-mass objects whose shapes have yet to be determined.
The largest known trans-Neptunian objects are Pluto and Eris, followed by Haumea, Makemake, Gonggong, Quaoar, Sedna, and Orcus, all of them being officially recognized as dwarf planets by the IAU except for Gonggong, Sedna, and Orcus. There are also many possible dwarf planets, such as Salacia, (307261) 2002 MS 4, Varda, Ixion, and Varuna.
Mass of planet (M J) Semi-major axis Discovery method Discovery year Note Reference WD 0806-661: single 1.5-8 2500 direct imaging: 2011 WD 0806-661 B can be interpreted as either a sub-brown dwarf or an exoplanet. [1] [2] WD J0914+1914: metal-polluted single 0.070 to 0.074: detection of accreted planet material via spectroscopy: 2019 likely ice ...
The number of dwarf planets in the Solar System is unknown. Estimates have run as high as 200 in the Kuiper belt [1] and over 10,000 in the region beyond. [2] However, consideration of the surprisingly low densities of many large trans-Neptunian objects, as well as spectroscopic analysis of their surfaces, suggests that the number of dwarf planets may be much lower, perhaps only nine among ...
The mass of the Orcus system is about 3.8 percent that of Eris, the most massive known dwarf planet (1.66 × 10 22 kg). [ 16 ] [ 37 ] The ratio of the mass of Vanth to that of Orcus was measured astrometrically with the ALMA submillimeter telescope and is 0.16 ± 0.02 with Vanth containing 13.7% ± 1.3% of the total system mass.