Kuiper belt object

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Kuiper belt binary object

Kuiper belt object

astronomy

Also known as: KBO, TNO, trans-Neptunian object

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July 23, 2026

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Kuiper belt binary object — Kuiper belt binary object An artist's rendition of a binary object in the Kuiper belt. The two objects depicted orbit each other at the edge of the solar system.

The Kuiper belt is a region of icy bodies orbiting the Sun beyond Neptune. It is thought to be composed of hundreds of millions of objects, remnants from the formation of the outer planets. This belt is considered the source of most short-period comets.12

Notable Kuiper belt objects (KBOs) include Pluto, Eris, Makemake, and Haumea. These objects are also known as trans-Neptunian objects (TNOs). Due to the discovery of large KBOs like Eris, Pluto was reclassified as a dwarf planet in 2006. KBOs are categorized into different orbital subpopulations, such as resonant objects, hot classicals, and cold classicals.134

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Kuiper belt
…may represent the transition from Kuiper belt objects [KBOs] to short-period comets.) Although its existence had been assumed for decades, the Kuiper belt remained undetected until the 1990s, when the prerequisite large telescopes and sensitive light detectors became available.
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…may represent the transition from Kuiper belt objects [KBOs] to short-period comets.) Although its existence had been assumed for decades, the Kuiper belt remained undetected until the 1990s, when the prerequisite large telescopes and sensitive light detectors became available.
Read More

Jane Luu
Astronomy
…1992 QB1, the first acknowledged object in the Kuiper Belt, a flat ring of icy small bodies that revolve around the Sun beyond the orbit of the planet Neptune. The body is about 200–250 km (125–155 miles) in diameter, as estimated from its brightness. It moves in a nearly circular…
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…1992 QB1, the first acknowledged object in the Kuiper Belt, a flat ring of icy small bodies that revolve around the Sun beyond the orbit of the planet Neptune. The body is about 200–250 km (125–155 miles) in diameter, as estimated from its brightness. It moves in a nearly circular…
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Planet Nine
In 2014 some Kuiper belt objects (KBOs) were found to be moving in similar orbits. American astronomers Michael Brown and Konstantin Batygin postulated in 2016 that the similarity in orbits could be caused by the presence of a planet with a mass more than 10 times that of…
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In 2014 some Kuiper belt objects (KBOs) were found to be moving in similar orbits. American astronomers Michael Brown and Konstantin Batygin postulated in 2016 that the similarity in orbits could be caused by the presence of a planet with a mass more than 10 times that of…
Read More

Pluto
Origin of Pluto and its moons
After more than a thousand Kuiper belt objects (KBOs) were directly observed starting in the early 1990s, astronomers came to the conclusion that Pluto and Charon likely are large members of the Kuiper belt and that bodies such as Chiron, Neptune’s moon Triton, and a number of other icy moons…
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After more than a thousand Kuiper belt objects (KBOs) were directly observed starting in the early 1990s, astronomers came to the conclusion that Pluto and Charon likely are large members of the Kuiper belt and that bodies such as Chiron, Neptune’s moon Triton, and a number of other icy moons…
Read More