Dwarf Planets, About Dwarf Planet, Euler Diagram, Are Asteroids Dwarf Planets

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Dwarf Planets

They Are Heavenly Bodies That Are Too Small to Be Considered a Planet but Too Large to Fall under Smaller Categories.

About Dwarf Planet

• The International Astronomical Unit defines a planet as something that obeys the following criteria:
  • To be in orbit around the Sun
  • Has enough gravity to pull its own mass into a round shape
  • Has cleared its orbit of smaller objects
• Planets and dwarf planets differ at the last point.
• A planet՚s gravity would either attract or push away smaller bodies that obstruct its orbit, but the gravity of the dwarf planet is not sufficient to make this happen.
• Recently, five dwarf planets have been discovered.
  • Ceres
  • Pluto
  • Eris
  • Haumea
  • Makemake
• Scientists presume that there may be more than a hundred dwarf planets awaiting discovery.
• The number of dwarf planets in the Solar System is unknown. This is because determining whether a body is in hydrostatic equilibrium requires close observation by spacecraft.
• The half-dozen largest candidates have either been visited by spacecraft (Pluto and Ceres) or have at least one known moon (Pluto, Eris, Haumea, Makemake, Gonggong, Quaoar), which allows their masses and thus an estimate of their densities to be determined. Mass and density in turn can be fit into models of hydrostatic equilibrium.

Euler Diagram

Why Was Pluto Reclassified as a Dwarf Planet?

• From 1930 to 2006, Pluto was classified as a planet and then later re-classified as a dwarf planet.
• Pluto was always an oddity. Pluto՚s orbit was peculiar that at times it was closer to the sun than Neptune.
• Things came to light in 2003, when astronomer Michael Brown discovered Eris, an object identical in size to Pluto, in the same outer region of the solar system.
• In 2006, the IAU coined the term “dwarf planet” and applied it to both Pluto and Eris.

Are Asteroids Dwarf Planets?

• No, asteroids are not dwarf planets.
• The rocky bodies that orbit the sun primarily in the asteroid belt between Jupiter and Mars are known as asteroids.
• Most asteroids do not pull themselves into a spherical shape, so they don՚t qualify as dwarf planets.