Artist's rendering of the Kuiper Belt and hypothetical more distant Oort cloud.

The Kuiper belt (pronounced /ˈkaɪpɚ/) is an area of the solar system extending from the orbit of Neptune (at 30 AU) to 50 AU from the Sun. Image File history File links Kuiper_oort. ... Image File history File links Kuiper_oort. ... This image is an artists rendering of the Oort cloud and the Kuiper Belt. ... This is a concise version of the International Phonetic Alphabet for English sounds. ... Major features of the solar system (not to scale) The solar system comprises the Sun and the retinue of celestial objects gravitationally bound to it: nine planets and their 158 currently known moons, as well as asteroids, meteoroids, planetoids, comets, and interplanetary dust. ... In physics, an orbit is the path that an object makes, around another object, whilst under the influence of a source of centripetal force, such as gravity. ... Atmospheric characteristics Surface pressure ≫100 MPa Hydrogen - H2 80% ±3. ... The astronomical unit (AU or au or a. ... To help compare different distances this page lists lengths starting at 1012 m (1000 million km). ... The Sun is the star at the center of our solar system. ...

The objects within the Kuiper Belt together with the members of the scattered disk extending beyond, are collectively referred to as trans-Neptunian. The scattered disc (or scattered disk) is a distant region of our solar system, thinly populated by icy planetoids known as scattered disk objects (SDOs), a subset of the broader family of trans-Neptunian objects (TNOs). ... A trans-Neptunian object (TNO) is any object in the solar system that orbits the sun at a greater distance on average than Neptune. ...

The interaction with Neptune (2:1 orbital resonance) is thought to be responsible for the apparent edge at 48 AU (a sudden drop in number of objects, see Orbit distribution below) but the current models have yet to explain this peculiar distribution in detail. In celestial mechanics, an orbital resonance occurs when two orbiting bodies exert a regular, periodic gravitational influence on each other. ...

Origins

These debris disks around the two remote stars seem equivalent of our own solar system's Kuiper Belt. The left image is the "top view", and the right image "edge view". The black central circle is produced by the camera's coronagraph which hides the central star to allow the much fainter disks to be seen. Observed with Hubble

Modern computer simulations show the Kuiper belt to have been strongly influenced by Jupiter and Neptune. During the early period of the Solar System, Neptune's orbit is thought to have migrated outwards from the Sun due to interactions with minor bodies. In the process, Neptune swept up, or gravitationally ejected all the bodies closer to the Sun than about 40 AU (the inner edge of the region occupied by cubewanos), apart from those which fortuitously were in a 2:3 orbital resonance. These resonant bodies formed the plutinos. The present Kuiper Belt members are thought to have largely formed in their present position, although a significant fraction may have originated in the vicinity of Jupiter, and been ejected by it to the far regions of the Solar system. Image File history File links Download high resolution version (2908x1524, 786 KB) The two dusty planetary disks around the nearby stars resemble our Kuiper belt. ... Image File history File links Download high resolution version (2908x1524, 786 KB) The two dusty planetary disks around the nearby stars resemble our Kuiper belt. ... See: Hubble Space Telescope Edwin Hubble Hubbles law Hubble sequence This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... A Lego RCX Computer is an example of an embedded computer used to control mechanical devices. ... Wooden mechanical horse simulator during WWI. A simulation is an imitation of some real thing, state of affairs, or process. ... Atmospheric characteristics Atmospheric pressure 70 kPa Hydrogen ~86% Helium ~14% Methane 0. ... Adjective Neptunian Atmospheric characteristics Surface pressure ≫100 MPa Hydrogen - H2 80% ±3. ... Major features of the solar system (not to scale) The solar system comprises the Sun and the retinue of celestial objects gravitationally bound to it: nine planets and their 158 currently known moons, as well as asteroids, meteoroids, planetoids, comets, and interplanetary dust. ... A cubewano is any substantial Kuiper belt object, orbiting beyond about 41 AU and not controlled by resonances with the outer planets. ... In celestial mechanics, an orbital resonance occurs when two orbiting bodies exert a regular, periodic gravitational influence on each other. ... In astronomy, a plutino is a trans-Neptunian object that has a 3:2 orbital resonance with Neptune. ...

Hypothesis

The first astronomers to suggest the existence of this belt were Frederick C. Leonard in 1930 and Kenneth E. Edgeworth in 1943. In 1951 Gerard Kuiper suggested that the belt was the source of short period comets (those having an orbital period of less than 200 years). More detailed conjectures about objects in the belt were done by Al G. W. Cameron in 1962, Fred L. Whipple in 1964, and Julio Fernandez in 1980. The belt and the objects in it were named after Kuiper after the discovery of (15760) 1992 QB₁. An astronomer or astrophysicist is a scientist whose area of research is astronomy or astrophysics. ... 1930 (MCMXXX) is a common year starting on Wednesday. ... LCol Kenneth Essex Edgeworth (26 February 1880 - 10 October 1972) was an Irish astronomer, economist and engineer. ... 1943 (MCMXLIII) was a common year starting on Friday (the link is to a full 1943 calendar). ... 1951 (MCMLI) was a common year starting on Monday; see its calendar. ... Gerard Kuiper, circa 1963. ... Comet Hale-Bopp For other uses, see Comet (disambiguation). ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... A year is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... 1962 (MCMLXII) was a common year starting on Monday (the link is to a full 1962 calendar). ... Fred Lawrence Whipple (November 5, 1906–August 30, 2004) was an American astronomer. ... 1964 (MCMLXIV) was a leap year starting on Wednesday (the link is to a full 1964 calendar). ... Julio M. Fernandez (born 1954 in Santiago, Chile) is a Professor in the Department of Biological Sciences at Columbia University, New York. ... 1980 (MCMLXXX) was a leap year starting on Tuesday. ... (15760) 1992 QB1 (also written (15760) 1992 QB1) was the first trans-Neptunian object to be discovered after Pluto and Charon. ...

Name

An alternative name, Edgeworth-Kuiper belt is used to credit Edgeworth. The term trans-Neptunian object is recommended for objects in the belt by several scientific groups because the term is less controversial than all others — it is not a synonym though, as TNOs include all objects orbiting the Sun at the outer edge of the solar system, not just those in the Kuiper belt. A trans-Neptunian object (TNO) is any object in the solar system that orbits the sun at a greater distance on average than Neptune. ...

Discoveries thus far

Over 800 Kuiper belt objects (KBOs) (a subset of trans-Neptunian objects (TNOs)) have been discovered in the belt, almost all of them since 1992. Among the largest are Pluto and Charon, but since the year 2000 other large objects that approached their size were identified. 50000 Quaoar, discovered in 2002, which is a KBO, is half the size of Pluto and is larger than the largest asteroid, 1 Ceres. 2005 FY₉ "Zenn" and 2003 EL₆₁ "Santa", both announced on 29 July 2005, are larger still. Other objects, such as 28978 Ixion (discovered in 2001) and 20000 Varuna (discovered in 2000) while smaller than Quaoar, are nonetheless quite sizable. Sedna, a small red planetoid with a diameter roughly half-way between Pluto and Quaoar, was first sighted on november 14th 2003. The exact classification of these objects is unclear, since they are probably fairly different from the asteroids of the asteroid belt. The largest recent discovery is 2003 UB313, nicknamed Xena. It has led scientists to question the definition of the term Planet, as it is larger than Pluto and has already been called a tenth planet by some sources [1]. The centaurs are a class of icy planetoids that orbit the Sun between Jupiter and Neptune, named after the mythical race of centaurs. ... Adjective Neptunian Atmospheric characteristics Surface pressure ≫100 MPa Hydrogen - H2 80% ±3. ... A trans-Neptunian object (TNO) is any object in the solar system that orbits the sun at a greater distance on average than Neptune. ... A cubewano is any substantial Kuiper belt object, orbiting beyond about 41 AU and not controlled by resonances with the outer planets. ... In astronomy, a plutino is a trans-Neptunian object that has a 3:2 orbital resonance with Neptune. ... While a Plutino completes 2 orbits around the Sun in the time it takes Neptune to complete 3 orbits, a Twotino makes 1 orbit around the Sun in the time it takes Neptune to complete 2 orbits. ... The scattered disc (or scattered disk) is a distant region of our solar system, thinly populated by icy planetoids known as scattered disk objects (SDOs), a subset of the broader family of trans-Neptunian objects (TNOs). ... This image is an artists rendering of the Oort cloud and the Kuiper Belt. ... A trans-Neptunian object (TNO) is any object in the solar system that orbits the sun at a greater distance on average than Neptune. ... 1992 (MCMXCII) was a leap year starting on Wednesday. ... Atmospheric characteristics Atmospheric pressure 0. ... Media:Example. ... This article is about the year 2000. ... Artists impression by G. Bacon of STScI / NASA 50000 Quaoar (pronounced kwah·war, kwah·wor, or kwow·ur, Tongva ) [1] is a Trans-Neptunian object orbiting the Sun in the Edgeworth-Kuiper belt. ... For album titles with the same name, see 2002 (album). ... An asteroid is a small, solid object in our Solar System, orbiting the Sun. ... 1 Ceres (, Latin CerÄ“s) was the first asteroid to be discovered. ... 2005 FY9 (also written 2005 FY9), codenamed Easterbunny by its discoverers, is a very large Kuiper belt object discovered on March 31, 2005 by the team led by Michael Brown. ... 2003 EL61 (also written 2003 EL61), nicknamed Santa (non-official designation), is a large and very unusual Kuiper belt object discovered by Mike Brown at Caltech in the United States. ... July 29 is the 210th day (211th in leap years) of the year in the Gregorian Calendar, with 155 days remaining. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ... (28978) Ixion (ik·sye·un) is a Kuiper belt object discovered on May 22, 2001 with a diameter of < 822 km and a semimajor axis of about 39. ... 20000 Varuna (VAR oo na) is a Kuiper Belt object about 1060 km in diameter, estimated from a combination of thermal and optical measurements. ... 90377 Sedna is a trans-Neptunian object, discovered by Michael Brown (Caltech), Chad Trujillo (Gemini Observatory) and David Rabinowitz (Yale University) on November 14, 2003. ... An asteroid is a small, solid object in our Solar System, orbiting the Sun. ... Image of the main asteroid belt between the orbits of Mars and Jupiter. ... 2003 UB313 is a trans-Neptunian object (TNO) believed to be larger than the planet Pluto. ... The planet Neptune and its moon Triton, taken by Voyager 2 as it entered the outer solar system The definition of planet has proven elusive despite the term being one of the best-known astronomical words. ... Adjective Plutonian Atmospheric characteristics Atmospheric pressure 0. ... Ever since the discovery of Pluto, the existence of a tenth planet has been speculated by astronomers and the general public alike. ...

Neptune's moon Triton is commonly thought to be a captured KBO. Triton (trye-tÉ™n, IPA , Greek Τρίτων), or Neptune I, is the planet Neptunes largest moon. ...

Classification and Distribution

Resonant and classical objects

Orbit classification (schematic of semi-major axes).

Orbital resonance with Neptune is the major factor of the current classification of KBO, even if the majority (>600 objects as of October 2005) is not resonant. These objects, called Classical Kuiper Belt objects or cubewanos, are found between the 2:3 resonance (at ~39.4AU, populated by >150 plutinos) and the 1:2 resonance (at ~47.7AU, populated by a few twotinos). Minor resonances exist at 3:4, 3:5, 4:7 and 2:5 (this last, also fairly strongly occupied). The 1:2 resonance appears to be an edge. It is not clear whether it is actually the outer edge of the Classical Belt or just the beginning of a gap. Image File history File links TheKuiperBelt_classes. ... Image File history File links TheKuiperBelt_classes. ... The semi-major axis of an ellipse In geometry, the term semi-major axis (also semimajor axis) is used to describe the dimensions of ellipses and hyperbolae. ... In celestial mechanics, an orbital resonance occurs when two orbiting bodies exert a regular, periodic gravitational influence on each other. ... A cubewano is any substantial Kuiper belt object, orbiting beyond about 41 AU and not controlled by resonances with the outer planets. ... In astronomy, a plutino is a trans-Neptunian object that has a 3:2 orbital resonance with Neptune. ... While a Plutino completes 2 orbits around the Sun in the time it takes Neptune to complete 3 orbits, a Twotino makes 1 orbit around the Sun in the time it takes Neptune to complete 2 orbits. ...

Large cubewanos, plutinos and near scattered objects.

The next diagram shows the largest objects of the Kuiper belt: Pluto with the largest plutinos: 90482 Orcus and 28978 Ixion, a few big classical objects, and two scattered objects (beyond the 1:2 resonance, in grey), notably 2003 UB₃₁₃ thought to be the biggest trans-Neptunian object known. The eccentricity of the orbits is represented by the red segments (extending from perihelion to aphelion) with inclination represented on Y axis. While eccentric orbits of many resonant KBOs bring them periodically inside Neptune's orbit, classical KBOs are in more circular orbits (short red segments, Quaoar). Image File history File links TheKuiperBelt_75AU_Large. ... Image File history File links TheKuiperBelt_75AU_Large. ... A cubewano is any substantial Kuiper belt object, orbiting beyond about 41 AU and not controlled by resonances with the outer planets. ... In astronomy, a plutino is a trans-Neptunian object that has a 3:2 orbital resonance with Neptune. ... The scattered disc (or scattered disk) is a distant region of our solar system, thinly populated by icy planetoids known as scattered disk objects (SDOs), a subset of the broader family of trans-Neptunian objects (TNOs). ... Adjective Plutonian Atmospheric characteristics Atmospheric pressure 0. ... In astronomy, a plutino is a trans-Neptunian object that has a 3:2 orbital resonance with Neptune. ... 90482 Orcus (originally known by the provisional designation 2004 DW) is a Kuiper Belt object (KBO) that was discovered by Michael Brown of Caltech, Chad Trujillo of the Gemini Observatory, and David Rabinowitz of Yale University. ... (28978) Ixion (ik·sye·un) is a Kuiper belt object discovered on May 22, 2001 with a diameter of < 822 km and a semimajor axis of about 39. ... The scattered disc (or scattered disk) is a distant region of our solar system, thinly populated by icy planetoids known as scattered disk objects (SDOs), a subset of the broader family of trans-Neptunian objects (TNOs). ... 2003 UB313 is a trans-Neptunian object (TNO) believed to be larger than the planet Pluto. ... In astrodynamics, under standard assumptions any orbit must be of conic section shape. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... A diagram of Keplerian orbital elements. ... Inclination in general is the angle between a reference plane and another plane or axis of direction. ... This article is about the trans-Neptunian object. ...

Initially, the Kuiper belt was thought to be a flat belt (populated by objects on moderately eccentric, low-inclination orbits), as opposed to high inclination orbits of the "scattered" disk objects. With the discovery of the large cubewanos, this belt became a thick disk or torus. It now appears that the distribution of orbit inclinations peaks around 4 and 30-40 degrees, giving rise to a division into two groups: cold and hot, respectively. The cold group would have been born outside the Neptune's orbit while the hot migrated outwards due to close interactions with Neptune. The cold/hot terminology comes from analogy to particles in a gas, where as temperature rises, so do the relative velocities between the particles. A torus. ...

This grouping may yet be revised, however, as the current distribution of known objects is likely to be strongly affected by observational bias. Most observations have so far focused on near-ecliptic objects. Even objects with high inclinations (e.g. 2004 XR₁₉₀) were actually found at near ecliptic positions. In addition, most of the known KBOs are detected near their closest approaches to the Sun since they appear dimmer at greater distances.
The correct title of this article is 2004 XR190. ...

Orbit distribution

Distribution of cubewanos, plutinos and near scattered objects.

The last diagram shows the distribution of known Kuiper Belt objects. The resonant objects: Neptune Trojans (1:1 resonance), plutinos (2:3) , twotinos (1:2) and a handful of objects occupying other resonances are shown in red. Confirmed plutinos are plotted in dark red. Beyond the 1:2 resonance, scattered disk objects are plotted for reference. Image File history File links TheKuiperBelt_75AU_All. ... Image File history File links TheKuiperBelt_75AU_All. ... A cubewano is any substantial Kuiper belt object, orbiting beyond about 41 AU and not controlled by resonances with the outer planets. ... In astronomy, a plutino is a trans-Neptunian object that has a 3:2 orbital resonance with Neptune. ... The scattered disc (or scattered disk) is a distant region of our solar system, thinly populated by icy planetoids known as scattered disk objects (SDOs), a subset of the broader family of trans-Neptunian objects (TNOs). ... In celestial mechanics, an orbital resonance occurs when two orbiting bodies exert a regular, periodic gravitational influence on each other. ... Adjective Neptunian Atmospheric characteristics Surface pressure ≫100 MPa Hydrogen - H2 80% ±3. ... In astronomy, a plutino is a trans-Neptunian object that has a 3:2 orbital resonance with Neptune. ... While a Plutino completes 2 orbits around the Sun in the time it takes Neptune to complete 3 orbits, a Twotino makes 1 orbit around the Sun in the time it takes Neptune to complete 2 orbits. ... A scattered disk object (or scattered disc object or SDO) is a trans-Neptunian object of the Kuiper belt with a very eccentric orbit. ...

Interestingly, low inclination regions which include the "cold" majority of cubewanos appear devoid of the largest objects (see diagram). The (observed) distribution has been a challenge to the theories of the formation of the Kuiper belt as it is far too complex to be explained simply as being the remains of the original accretion disk dating back to the formation of the Solar System. Numerous competing models are being developed, typically involving so called Neptune migration. It was suggested in the 80s that interaction between giant planets and a massive disk of small particles would not only scatter the disk but also cause (via momentum transfer) the giants to migrate to more distant orbits. While all four giant planets would be affected, Neptune could have migrated as far as 5AU outwards to reach its current position at around 30 AU. Such models can explain for example, the ‘trapping’ of small bodies into the plutino 2:3 resonances.

However, the present models still fail to account for many of the characteristics of the distribution and, quoting one of the scientific articles[2], the problems continue to challenge analytical techniques and the fastest numerical modeling hardware and software.

The belt should not be confused with the hypothesized Oort cloud, which is far more distant.
This image is an artists rendering of the Oort cloud and the Kuiper Belt. ...

Size distribution

Illustration of the power law.

Bright objects are rare compared with the dominant dim population, as expected from accretion models of origin, given that only some objects of a given size would have grown further. This relationship N(D), the population expressed as a function of the diameter, referred to as brightness slope, has been confirmed by observations. The slope¹ is inversely proportional to some power of the diameter D. Image File history File links TheKuiperBelt_PowerLaw2. ... Image File history File links TheKuiperBelt_PowerLaw2. ...

where the current measures ^[1] give q = 4 ±0.5.

The relationship is illustrated on the graph for q=4. Less formally, there is for instance 8 (=2³) times more objects in 100-200km range than objects in 200-400km range. In other words, for a single object with the diameter of 1000 km it should be there around 1000 (=10³) objects with diameter of 100km. Of course, only the magnitude is actually known, the size is inferred assuming albedo (not a safe assumption for larger objects)

¹The law is expressed in this differential form rather than as a cumulative cubic relationship, because only the middle part of the slope can be measured; the law must break at smaller sizes, beyond the current measure.

Missing mass dilemma

The total mass of Kuiper Belt objects can be inferred by models of the origin of the Solar System from the known mass of the planets and known distribution of mass closer to the Sun. While the estimates are model-dependent, the total mass of around 30 M_Earth is expected. Surprisingly, the actual distribution appears to be well below that value, even accounting for the observational bias. The observed density is at least 100 times smaller ^[2]than the model calls for. This missing 99% of the mass can be hardly dismissed as it is required for the accretion of bigger (>100km) objects ever taking place. At the current low density these objects simply could not be created. Moreover, the eccentricity and inclination of current orbits makes the encounters quite "violent" resulting in destruction rather than accretion. It appears that either the current residents of the Kuiper belt have been created closer to the Sun or some mechanism dispersed the original mass. Neptune’s influence is too weak to explain such a massive "vacuuming". While the question remains open, the conjectures^[3] vary from a passing star scenario to grinding of smaller objects, via collisions, into dust small enough to be affected by Solar radiation.

The term "Kuiper belt object"

Most models of solar system formation show icy planetoids first forming in the Kuiper belt, while later gravitational interactions displace some of them outwards into the so-named scattered disc. Strictly speaking, a KBO is any object that orbits exclusively within the defined Kuiper belt region regardless of origin or composition. However, in some scientific circles the term has become synonymous with any icy planetoid native to the outer solar sytem believed to have been part of that initial class, even if its orbit during the bulk of solar system history has been beyond the Kuiper belt (e.g. in the scattered disk region). Discoverer Michael E. Brown, for instance, has referred to 2003 UB₃₁₃ as a KBO, despite it having a mean orbital radius of 67 AU, well clear of the Kuiper cliff. Other leading trans-Neptunian researchers have been more cautious in applying the KBO label to objects clearly outside the belt in the current epoch. The scattered disc (or scattered disk) is a distant region of our solar system, thinly populated by icy planetoids known as scattered disk objects (SDOs), a subset of the broader family of trans-Neptunian objects (TNOs). ... Dr. Michael (Mike) E. Brown has been an associate professor of planetary astronomy at the California Institute of Technology (Caltech) since 2002. ... 2003 UB313 is a trans-Neptunian object (TNO) believed to be larger than the planet Pluto. ...

List of the brightest KBOs

The brightest known KBOs (with absolute magnitudes < 4.0), are: In astronomy, absolute magnitude is the apparent magnitude, m, an object would have if it were at a standard luminosity distance away from us (in the absence of interstellar extinction!). It allows the overall brightnesses of objects to be compared without regard to distance. ...

There is also a separate list of the brightest scattered disk objects. In geometry, the semi-major axis (also semimajor axis) a applies to ellipses and hyperbolas. ... Atmospheric characteristics Atmospheric pressure 0. ... 1930 (MCMXXX) is a common year starting on Wednesday. ... Clyde William Tombaugh (February 4, 1906 – January 17, 1997) was an American astronomer who discovered the planet Pluto in 1930. ... In this July, 1997 still frame captured from video, the bright star Aldebaran has just reappeared on the dark limb of the waning crescent moon in this predawn occultation. ... 2005 FY9 (also written 2005 FY9), codenamed Easterbunny by its discoverers, is a very large Kuiper belt object discovered on March 31, 2005 by the team led by Michael Brown. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ... Dr. Michael (Mike) E. Brown has been an associate professor of planetary astronomy at the California Institute of Technology (Caltech) since 2002. ... Chadwick A. Chad Trujillo (born November 22, 1973) is a postdoctoral scholar at Caltech researching the Kuiper belt and the outer solar system. ... David Lincoln Rabinowitz (born 1960) is a researcher at Yale University studying the Kuiper belt and the outer solar system. ... 2003 EL61 (also written 2003 EL61), nicknamed Santa (non-official designation), is a large and very unusual Kuiper belt object discovered by Mike Brown at Caltech in the United States. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ... Dr. Michael (Mike) E. Brown has been an associate professor of planetary astronomy at the California Institute of Technology (Caltech) since 2002. ... Chadwick A. Chad Trujillo (born November 22, 1973) is a postdoctoral scholar at Caltech researching the Kuiper belt and the outer solar system. ... David Lincoln Rabinowitz (born 1960) is a researcher at Yale University studying the Kuiper belt and the outer solar system. ... Media:Example. ... 1978 (MCMLXXVIII) was a common year starting on Sunday (the link is to a full 1978 calendar). ... James Walter Christy (born 1938) is an American astronomer. ... In this July, 1997 still frame captured from video, the bright star Aldebaran has just reappeared on the dark limb of the waning crescent moon in this predawn occultation. ... 90482 Orcus (originally known by the provisional designation 2004 DW) is a Kuiper Belt object (KBO) that was discovered by Michael Brown of Caltech, Chad Trujillo of the Gemini Observatory, and David Rabinowitz of Yale University. ... 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ... Dr. Michael (Mike) E. Brown has been an associate professor of planetary astronomy at the California Institute of Technology (Caltech) since 2002. ... Chadwick A. Chad Trujillo (born November 22, 1973) is a postdoctoral scholar at Caltech researching the Kuiper belt and the outer solar system. ... David Lincoln Rabinowitz (born 1960) is a researcher at Yale University studying the Kuiper belt and the outer solar system. ... This article is about the trans-Neptunian object. ... For album titles with the same name, see 2002 (album). ... Chadwick A. Chad Trujillo (born November 22, 1973) is a postdoctoral scholar at Caltech researching the Kuiper belt and the outer solar system. ... Dr. Michael (Mike) E. Brown has been an associate professor of planetary astronomy at the California Institute of Technology (Caltech) since 2002. ... (Redirected from (28978) Ixion) 28978 Ixion (ik SIGH un, sometimes ICK see un) is a Kuiper belt object discovered on May 22, 2001 with a diameter of approximately 1055 km and a semimajor axis of about 39. ... 2001: A Space Odyssey. ... The Deep Ecliptic Survey is a project to find Kuiper belt objects, using the facilities of the National Optical Astronomy Observatory. ... The correct title of this article is (55636) 2002 TX300. ... For album titles with the same name, see 2002 (album). ... Near Earth Asteroid Tracking (NEAT) is a program run by NASA and Jet Propulsion Laboratory to discover near-Earth objects. ... (55565) 2002 AW197 (also written: (55565) 2002 AW197) is a trans-Neptunian object. ... For album titles with the same name, see 2002 (album). ... Chadwick A. Chad Trujillo (born November 22, 1973) is a postdoctoral scholar at Caltech researching the Kuiper belt and the outer solar system. ... Dr. Michael (Mike) E. Brown has been an associate professor of planetary astronomy at the California Institute of Technology (Caltech) since 2002. ... Eleanor Francis Helin is an American astronomer, principal investigator of the Near Earth Asteroid Tracking (NEAT) program of NASAs Jet Propulsion Laboratory. ... Kenneth J. Lawrence is an American astronomer. ... Palomar Observatory is a privately-owned observatory located in San Diego County, California, 90 miles (145 km) southeast of Mount Wilson Observatory, on Palomar Mountain. ... The correct title of this article is (55637) 2002 UX25. ... For album titles with the same name, see 2002 (album). ... Spacewatch is a project at the University of Arizona that specializes in the study of minor planets, and including various types of asteroids and comets. ... (Redirected from (20000) Varuna) 20000 Varuna (VAR oo na) is a Kuiper Belt object about 1060 kilometers in diameter, estimated from a combination of thermal and optical measurements. ... This article is about the year 2000. ... Robert S. McMillan is an astronomer at the University of Arizona, and heads the Spacewatch project, which studies minor planets. ... The scattered disc (or scattered disk) is a distant region of our solar system, thinly populated by icy planetoids known as scattered disk objects (SDOs), a subset of the broader family of trans-Neptunian objects (TNOs). ...

External links and data sources

• Dave Jewitt's page @ University of Hawaii
  • The belt's name
• The Kuiper Belt Electronic Newsletter
• Wm. Robert Johnston's TNO page
• Minor Planet Center: Plot of the Outer Solar System, illustrating Kuiper gap
• Website of the International Astronomical Union (debating the status of TNOs)
• XXVIth General Assembly 2006
• nature.com article: diagram displaying inner solar system, Kuiper Belt, and Oort Cloud

References

1. ^ Bernstein G.M., Trilling D.E., Allen R.L. , Brown K.E , Holman M., Malhotra R. The size Distribution of transneptunian bodies. The Astronomical Journal, 128, 1364-1390. preprint on arXiv (pdf)
2. ^ D.Jewitt,A.Delsanti The Solar System Beyond The Planets,to appear in the book Solar System Update, Springer-Praxis Ed., Horwood, Blondel and Mason, 2006. Preprint version (pdf)
3. ^ Morbidelli A. Origin and dynamical evolution of comets and their reservoirs. Preprint on arXiv (pdf)

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