Карликовые планеты

Currently, six bodies have the official status of dwarf planets in the solar system – these are Pluto (49.31 AU), Eris (97.65 AU), Makemake (52.82 AU), Ceres (2.98 AU), Sedna (960 AU) and Haumea (51.60 AU). However, the issue has not been fully resolved with Sedna.

   Kuiper Belt

The Kuiper Belt is a ring-shaped region of icy bodies beyond the orbit of Neptune. Like the asteroid belt, it contains millions of small bodies, all remnants from the formation of the
Solar System. These icy objects are also called trans-Neptunian objects (TNOs) or Kuiper Belt objects.The Kuiper Belt extends from the orbit of Neptune to 55 AU from the
Sun.The Kuiper Belt is home to many dwarf planets, including Pluto, Eris, Haumea and Makemake. Most objects in the Kuiper Belt are made of icy volatile substances such as water, ammonia and methane.

Criteria for dwarf planets

They rotate strictly in orbit around the Sun.
They have sufficient mass in order, unlike small bodies of the solar system, to maintain a shape close to spherical under the influence of gravitational forces.
They cannot clear the area of their orbit from other objects, i.e. they do not dominate their orbit.They are not satellites.

Pluto

Ceres

Ceres is the largest object of the asteroid belt, and contains about a third of the entire mass of the belt. It makes one turn in 4.5 years.
This dwarf planet was discovered much earlier than others because of its proximity.
Scientists believe that Ceres consists of a rocky core surrounded by a thick mantle of water ice.

Makekame

Erida

Due to the huge distance and as a consequence of the low apparent brightness, we still know very little about Eris.
The temperature on the surface is -253 ° C.The period of rotation around the Sun is 558 years.
The planet has an open satellite Dysnomia about 150 km in diameter
Spectroscopic observations have shown the presence of methane snow on the surface of Eris, in which there is an admixture of nitrogen ice, the proportion of which increases with depth.

Sedna

The diameter is estimated at about 1000 km.
Sedna has the longest orbital period among the known large objects in the solar system, which is approximately 11487 years.
The detection of methane and water ice was confirmed in 2006 using the Spitzer Telescope.
During a 200-year period in the vicinity of perihelion, the maximum temperature on Sedna should exceed -237 ° C.
It is one of the reddest in the solar system. The dye of the planet's surface is thallium.

Haumea

This dwarf planet is kilometers across, which is almost the size of Pluto, but it is three times lighter than it.
The planet makes one revolution around its axis in just 4 hours, which also makes it one of the fastest rotating bodies in our system.
Huamea makes a complete revolution around the Sun in 283 years.