Kuiper Belt - Agreed Terms - NEW May 2022


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Kuiper Belt - NEW - Agreed Terms - May 2022

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Start dateMar 30, 2022



Kuiper Belt – Agreed Terms - New and Extended:

Comets, Meteors and Asteroids” by John Man BBC 2001

“Kuiper Belt

This belt of icy bodies is named after the Dutch-American astronomer Gerard Kuiper, who suggested its existence in 1951. The suggestion became more attractive in 1980, when Julio Fernandez of the National Astronomy Observatory, Madrid, pointed out that most short-period comets orbited in the same plane as the planets, and ought therefore to have their origins in an extension of the disc of dust and gas from which the planets had condensed. For a few years, this remained a theory. Then in the mid 1980s, USA’s Infrared Astronomical Sattelite (IRAS) photographed such a belt around a star in the constellation Pictor. Then, in 1992, David Jewitt and Jane Luu at the University of Hawaii spotted a tiny object, about 320 km (200 miles) across, orbiting beyond Neptune – the first Kuiper Belt Object (KBO).

Uranus, Neptune, Pluto and the Outer Solar System” by Linda T Elkins-Tanton Chelsea House 2006
Kuiper Belt and Kuiper Belt Objects

“Neptune’s orbit carries the planet from 29.8 to 30.3 AU from the Sun. Small bodies orbiting past Neptune are referred to as trans-Neptunian objects, and then are further sub-divided into members of the Kuiper Belt or the Oort Cloud. Neptune marks the inner edge of the Kuiper Belt. The Kuiper Belt was originally thought to reach from 35 to 100 AU from the Sun, and then to merge into the Oort Cloud of icy bodies. . . . . . . there (now) appears to be a gap between the edge of the Kuiper Belt and the beginning of the comet-rich Oort Cloud. The Kuiper Belt begins around 30 AU and has a sharp outer edge at 49 AU.” . . . . . . . . .

“The Kuiper Belt had been postulated since 1943, but it remained a theory until 1992. Only the development of a highly sensitive viewing instrument, called a charge-couple device has allowed astronomers to see the tiny bodies in the Kuiper Belt.” . . . . . . . . .

Kuiper Belt Bodies are divided into three classes according to their orbits; classical (or cubewano), resonance (or plutino), or scattered disk (object). Classical Kuiper Belt Objects have orbits with low eccentricity and low inclination, indicating that they formed from the solar nebula in place and have not been further perturbed. These objects are sometimes called cubewanos and include any large KBO orbiting between about 41 and 48 AU but not controlled by orbital resonances with Neptune. The name is derived from 1992 QB1, the first KBO found. Subsequent objects were called “que-be-one-os”, or cubewanos. There are about 524 cubewanos known as of 2004. Resonance Kuiper Belt Objects are protected from gravitational perturbation by integral ratios between their orbital periods and Neptune’s. Like Pluto, many KBOs have orbits in periods of 3:2 with Neptune. . . . Because they share their resonance with Pluto, they are called plutinos. As of 2005, there were about 150 plutinos and 22 other resonance objects.” . . . . .

“The third class, scattered disk (Kuiper Belt) objects, have large, eccentric orbits, perhaps created by gravitational interactions with the giant planets. There are about 100 known (2006) scattered disk objects. The KBO 1996TL66 is a good example of this class, with an orbital eccentricity of 0.59 that carries it to 130 AU at aphelion. There are thought to be as many as 10,000 scattered disk objects.”

Comets Visitors from Deep Space” by David J Eicher Cambridge University Press 2013

Kuiper Belt
A region of small Solar System bodies beyond the planets, extending from the orbit of Neptune (at about 30 AU from the Sun) to approximately 50 AU from the Sun. Named for Dutch American astronomer Gerard P Kuiper.

“Fundamental Planetary Science” by Jack Lissauer and Imke de Pater CUP 2019
“Kuiper Belt

The Kuiper Belt is a thick disk of ice/rock bodies beyond the orbit of Neptune. The two largest members of the Kuiper Belt to have been sighted are Eris, whose heliocentric distance oscillates between 38 and 97 AU, and Pluto, whose heliocentric distance varies from 29 to 50 AU. The radii of Eris and Pluto exceed 1000 km.”

Kuiper Belt Objects

Kuiper Belt Objects (KBOs) are icy bodies, and the largest KBOs are an order of magnitude more massive than 1 Ceres. The total mass of the Kuiper Belt exceeds that of the Asteroid Belt by about two orders of magnitude. Yet, because the Kuiper Belt is located much further from both the Earth and the Sun than the Asteroid Belt, more is known about asteroids than about KBOs.”

“The Kuiper Belt is also the primary source of the Short Period or Ecliptic Comets (ECs), comets that are on eccentric orbits near the ecliptic plane and return with regularity (orbital periods <200 years) to the inner Solar System.” See Oort Cloud for long-period comets (>~ 10,000 AU

Encyclopaedia of the Solar System” Academic Press Ed Weissman, McFadden and Johnson.
A mammoth book of over 1000 pages. The Kuiper Belt chapter takes up 26 pages, with a further 20 pages devoted to Pluto and Charon.
From Historical Perspective:

“The planets formed in a disk of material that originally surrounded the Sun. . . . . . . . . . Then there is Pluto, unique, having an orbital inclination of 15.6o . . . . . . . . . having an orbit that crosses the orbit of … Neptune. So, the historical view was that Pluto was an oddity in the Solar System. . . . This view, however, changed in September 1992 with the announcement of the discovery of the first of a population of small (compared to planetary bodies) objects orbiting beyond the orbit of Neptune, in the same region as Pluto. Since that time, 60 objects with radii between about 50 and 500 km have been discovered. . . . There are almost certainly very more smaller ones. . . . “

“The discovery of the Kuiper Belt, as it has come to be known, represents a revolution in our thinking about the Solar System. First predicted on theoretical grounds and later confirmed by observations, the Kuiper Belt is the first totally new class of bodies to be discovered in the Solar System since the first asteroid was found on New Year’s Day in 1801. . . . . . . “

“However, the idea was resurrected in 1980 when Julio Fernandez proposed that a cometary disk beyond Neptune could be a possible source reservoir for the short-period comets (those with orbital periods < 200 years). Subsequent dynamical simulations showed that a comet belt beyond Neptune is the most plausible source for the low inclination, Jupiter-family comets. This work led observers to search for Kuiper Belt objects, the first one being discovered by David Jewitt and Jane Luu in August 1992. Since then, over 60 KBOs with estimated radii >~50 km (assuming a typical cometary nucleus albedo pf 0.04) have been found by ground based searches, and about 30 comet-sized (radii <~10 km) objects have been detected using the Hubble Space Telescope. (Because the Kuiper Belt is believed to be the source of the Jupiter-family short-period comets, typical cometary albedos of 4% are assumed for the surfaces of KBOs.)”

“Two populations of objects in the Solar System are related to the Kuiper Belt. The first consists of a large number (~106) of (presumably) icy objects on planet-crossing orbits interior to Neptune’s orbit. These objects are known as ecliptic comets and they most likely originated in the Kuiper Belt. Ecliptic comets include two distinct subpopulations: Centaurs and Jupiter-family comets. Known Centaurs are 20- to 100- km-radius objects with semi-major axes beyond the orbit of Jupiter, most of which appear to be inactive (a notable exception is the first Centaur discovered, 2060 Chiron). Jupiter-family comets are much smaller objects a few kilometers in diameter on Jupiter-crossing orbits but with semimajor axes interior to Jupiter. Most of the known Jupiter-family comets are active comets, as active comets are much brighter and hence easier to detect than inactive ones.” . . . . . . . . .

“The second related population of objects is known as the scattered comet disk. (Discovered in) 1996, the scattered disk occupies the same volume of physical space as the Kuiper Belt, but has a different dynamical character and a different origin.” . . . . . . . . .

“It is rare in the history of astronomy that a whole new region of the Solar System is discovered that needs to be understood. . . . . . . . . . The discovery of duct disks around nearby stars by the IRAS satellite in 1983-4 suggests that Kuiper Belts may be a natural consequence of star and planet formation, thus providing us with a tool for studying solar system formation around other stars.

10 Need-to-Know Things About the Kuiper Belt – from NASA

The Kuiper Belt is a region of space. The known icy worlds and comets in both regions are much smaller than Earth's Moon.

The Kuiper Belt is a doughnut-shaped ring of icy objects around the Sun, extending just beyond the orbit of Neptune from about 30 to 55 AU.

Short-period comets (which take less than 200 years to orbit the Sun) originate in the Kuiper Belt.

There may be hundreds of thousands of icy bodies larger than 100 km (62 miles) and an estimated trillion or more comets within the Kuiper Belt.

Some dwarf planets within the Kuiper Belt have thin atmospheres that collapse when their orbit carries them farthest from the Sun.

Several dwarf planets within the Kuiper Belt have moons.

Egg-shaped Haumea has a ring around it.

The first mission to explore the Kuiper Belt is New Horizons. It flew past Pluto in 2015 and is on its way to explore another Kuiper Belt world.

It is not clear if worlds in this distant, cold region are capable of supporting life as we know it.

Astronomers are searching for a possible planet that might explain the strange orbits of several Kuiper Belt Objects. The nickname: Planet 9.

Frequently Asked Questions – from NASA
Where is the Kuiper Belt?

The inner edge of the Kuiper Belt begins at the orbit of Neptune, at about 30 AU from the Sun. (1 AU, or astronomical unit, is the distance from Earth to the Sun.)

The inner, main region of the Kuiper Belt ends around 50 AU from the Sun. Overlapping the outer edge of the main part of the Kuiper Belt is a second region called the scattered disk, which continues outward to nearly 1,000 AU, with some bodies on orbits that go even farther beyond.

How was the Kuiper Belt created?
Astronomers think the icy objects of the Kuiper Belt are remnants left over from the formation of the solar system. Similar to the relationship between the main asteroid belt and Jupiter, it's a region of objects that might have come together to form a planet had Neptune not been there. Instead, Neptune's gravity stirred up this region of space so much that the small, icy objects there weren't able to coalesce into a large planet.

Should Ceres still be in the Kuiper Belt? Where it originated?

Strange dwarf planet Ceres may have formed at the icy edges of the solar system, scientists suggest | Space

Uranus, Neptune, Pluto and the Outer Solar System” by Linda T Elkins-Tanton Chelsea House 2006
Kuiper Belt and Kuiper Belt Objects

In addition to the entry above, the following are listed as "selected Kuiper Belt and Oort Cloud Objects". Relevant details are added:


2003 UB12
2004 DW
2002 LM60
20000 Varuna
2000 WR106
2002 AW197
2002 TX300
28979 Ixion
2001 KX76
1999 CL119
1992 QB1

View: https://imgur.com/a/JohSF2r

There is some discussion on the presence of a planet size body in the Kuiper Belt, or possibly further:

'Planet Nine'? Cosmic Objects' Strange Orbits May Have a Different Explanation | Space

"Batygin and Brown didn't see Planet Nine; rather, they inferred its existence based on the odd orbital characteristics of six bodies in the "scattered disk" portion of the Kuiper Belt, a realm of icy bodies that lies beyond Neptune. For example, these six objects all have similar "arguments of perihelion." ['Planet Nine' Worlds Are the Most Common Ones We Know (Infographic)]

Researchers say an anomaly in the orbits of distant Kuiper Belt objects points to the existence of an unknown planet orbiting the sun. Here's what we know of this potential "Planet Nine." (Image credit: by Karl Tate, Infographics artist)
A body's argument of perihelion is basically the ratio of how much it pitches (wobbles forward or backward) to how much it rolls (moves left or right) as it orbits the sun, said Ann-Marie Madigan, a postdoctoral researcher at the University of California, Berkeley. This characteristic should be random from one Kuiper Belt object (KBO) to another, she added.
Imagine seeing a number of boats spread across San Francisco Bay that are all pitching and rolling in the same direction, and with the same pitch/roll ratio, Madigan said Jan. 26 during a talk at the SETI (Search for Extraterrestrial Intelligence) Institute in Mountain View, California."

Scattered Disk Objects
Fundamental Planetary Science
, Lissauer and de Pater Cambridge University Press 2019.

"An increasing number of TNOs are being detected on high eccentricity, non-resonant orbits with perihelia beyond the orbit of Neptune. These objects are referred to as Scattered Disk Objects (SDOs). The largest known SDO is 136199 Eris, whose mass is slightly larger than that of Pluto." Reference is made to Table E8, which gives Masses, Radii and Densities of 20 selected minor planets. The book also contains tables of information on large numbers of small Solar System objects. "The number of small SDOs is several times smaller than that of known CKBOs (Classical Kuiper Belt Objects). However, many of the SDOs travel on highly eccentric orbits and spend most of the time near aphelion, where they are quite faint. From the observed populations, the total mass of SDOs is estimated to be (very roughly) an order of magnitude larger than that of the Classical Kuiper Belt."
"The vast majority of SDOs are on orbits with perihelia between 33 AU and 40 AU. These bodies come close enough to the giant planets that they could have been placed in their current orbits by planetary perturbations, but they are far enough from Neptune that their orbits are stable on billion-year timescales. Nonetheless, some occasionally get close enough to Neptune to be scattered inwards on planet-crossing trajectories (discussed later), and this reservoir is the primary source of EC (Earth crossing) comets."
"The orbit of the TNO 90377 Sedna, with a perihelion at 76 AU and aphelion at ~ 900 AU, is exceptional. Sedna is often considered to be a member of the Inner Oort Cloud. Its orbit could have resulted from perturbations by a passing star (probably when the Solar System was very young and had not left its crowded stellar nursery) or by an unknown planet that may still orbit in the outer Solar System or may have escaped to interstellar space eons ago."

This was from Wiki. That probably means they all are. Well done NASA/Wiki.
Sorry if you cannot access these. Try Wiki direct to see if this helps.
HERE https://en.wikipedia.org/wiki/Trans-Neptunian_object

View: https://imgur.com/a/7objLwi

View: https://imgur.com/a/8OIETwT

View: https://imgur.com/a/75QTAOe

Dictionary of Geophysics, Astrophysics and Astronomy
Ed Richard A Matzner CRC Press
"In planetary dynamics, an orbital condition in which one object is periodically subjected to gravitational perturbations caused by another object. The two bodies are generally in orbit around a third, more massive object and their orbital periods are some whole number ratios of each other."
"For example, Io and Europa are in a resonance as they orbit around Jupiter. Io orbits twice for every orbit of Europa. Europa and Ganymede are also in a resonance, with Europa orbiting twice for every orbit of Ganymede, In the case of Io and Europa, the resonances cause tidal heating to be a major internal heat source for both objects. Resonances can also create gaps, such as the Kirkwood Gaps within the Asteroid Belt (when asteroids are in resonance with Jupiter) and several of the gaps within Saturn's Rings (caused by resonances with some of Saturn's moons.

View: https://imgur.com/a/Nt8DcoE

I have tried to indicate some topics and areas relevant to the KuiperBelt, please note that there is some overlap in terms and areas. In particular, since Ceres was promoted to Dwarf Planet, there is some confusion as to whether it should still be called an asteroid.


Edited and extended 7th May 2022 22.00 BST
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