Search results
Results from the WOW.Com Content Network
Dwarf planets were thus conceived of as a category of planet. In 2006, however, the concept was adopted by the International Astronomical Union (IAU) as a category of sub-planetary objects, part of a three-way recategorization of bodies orbiting the Sun: planets, dwarf planets, and small Solar System bodies. [2]
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 ...
Eris (minor-planet designation: 136199 Eris) is the most massive and second-largest known dwarf planet in the Solar System. [22] It is a trans-Neptunian object (TNO) in the scattered disk and has a high-eccentricity orbit. Eris was discovered in January 2005 by a Palomar Observatory–based team led by Mike Brown and verified later that year.
These lists contain the Sun, the planets, dwarf planets, many of the larger small Solar System bodies (which includes the asteroids), all named natural satellites, and a number of smaller objects of historical or scientific interest, such as comets and near-Earth objects.
Missions to dwarf planets in the outer Solar System necessitate careful planning and execution, with spacecraft hibernation employed specifically to conserve energy for the prolonged interplanetary journeys. This allows the spacecraft to endure the extended travel time while maintaining essential functions for navigation and communication.
Composite image showing the round dwarf planet Ceres; the slightly smaller, mostly round Vesta; and the much smaller, much lumpier Eros. The IAU definitions of planet and dwarf planet require that a Sun-orbiting astronomical body has undergone the rounding process to reach a roughly spherical shape, an achievement known as hydrostatic equilibrium.
The dwarf planet Pluto and its moon Charon are often described as a binary system in the Solar System, which orbit the Sun Main article: Binary asteroid When binary minor planets are similar in size, they may be called " binary companions " instead of referring to the smaller body as a satellite. [ 3 ]
Kepler-37e is listed with a radius of 0.37 ± 0.18 R 🜨 in the Exoplanet Archive based on KOI data, but the existence of this planet is doubtful, [22] and assuming its existence, a 2023 study found a mass of 8.1 ± 1.7 M 🜨, inconsistent with such a small radius.