Dwarf Planets Flashcards

Flashcards about Dwarf Planets

Dwarf Planet

A celestial object that satisfies the first two criteria to be a planet (orbits the Sun, spherical shape due to self-gravity) but has not cleared its orbit of debris.

Eris

A dwarf planet discovered in 2005, comparable in size and mass to Pluto, orbiting the Sun at 68 AU in a highly elliptical path. It has a companion moon, Dysnomia.

Pluto

A dwarf planet in the Kuiper belt with an average orbit radius of 39.5 AU. It has an elliptical path, a large axis tilt (113°), and spins in retrograde. Its surface composition includes frozen H2O, CO2, N2, CH4, and CO.

Surface of Pluto

Characterized by mountains as high as 3.5 km, made of rock-hard water ice, likely formed within the past 100 million years. It is one of the youngest surfaces seen in the solar system.

Ceres

A dwarf planet that orbits in the asteroid belt, discovered in 1801. It is the largest and most massive body in the main asteroid belt, containing about ¼ of the total asteroid mass in the asteroid belt.

Asteroid Belt

The region between the orbits of Mars and Jupiter that contains most of the asteroids in the Solar System

Composition of Ceres

It is hypothesized to have undergone differentiation with a rocky inner core, water-ice mantle, and a surface of hydrated (water) minerals. Evidence of organic material has been found around a northern-hemisphere crater.