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Related to plutoid: Black Mountains, Eris


A dwarf planet that orbits the sun at a greater distance on average than Neptune.

[Pluto + -oid.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
By May, New Horizons' photos should equal and then surpass the ones taken by the Hubble Space Telescope, with pictures of the plutoid and its moons improving with each passing day.
This definition excluded Pluto and reclassified it as a member of the new "dwarf planet" category (and specifically as a plutoid).
Though our solar system "lost" a planet when Pluto was re-classified as a plutoid in 2006, we have gained new solar systems with the discovery of extra-solar planets.
Then in 2008, the IAU introduced another classification, that of a plutoid (IAU, 2008).
There is no such planet, though it is often equated with Eris, a plutoid orbiting safely and permanently beyond Pluto.
The IAU has coined the term "plutoid" for objects like pluto, which, while massive enough to form a near-spherical shape, do not have gravitational influence to clear the neighbourhood around their orbit of other objects.
Scientists have decided that the planet will now be called "Plutoid." The reason for the change is because Pluto lost its planetary status when astronomers changed how they defined a planet.
The classification "plutoid" sets these objects apart from another solar system dwarf planet called Ceres, which resides in the asteroid belt between Mars and Jupiter, says Brian G.
Besides Pluto, the second known and named plutoid is called Eris.
Our new solar system of eight planets is defined and Pluto is classified as a plutoid. In just the first chapter, several facts contained in many current textbooks are updated.
Pluto and Eris are the first two members of a new class of objects called plutoids. The International Astronomical Union announced June 11 that the name plutoid will apply to any dwarf planet that orbits the sun beyond Neptune and that has enough mass for its self-gravity to give it a near-spherical shape.
Any TNO that is also a dwarf planet, is now called a "Plutoid".