Cosma / Communication / Knowledge / Realm / Physical / Universe / Solar System / Small Body / Centaur


GCSE Astronomy (Lawrence Smallman, YouTube Playlist)


Centaurs is a small Solar System body with either a perihelion or a semi-major axis between those of the outer planets. Centaurs generally have unstable orbits because they cross or have crossed the orbits of one or more of the giant planets; almost all their orbits have dynamic lifetimes of only a few million years. Centaurs typically exhibit the characteristics of both asteroids and comets. They are named after the mythological centaurs that were a mixture of horse and human. Observational bias toward large objects makes determination of the total centaur population difficult. Estimates for the number of centaurs more than 1 km in diameter range from 44,000 to more than 10,000,000. — Wikipedia

Centaur Object (Eric Weisstein’s World of Astronomy, Wolfram Research)
Centaur (COSMOS: The SAO Encyclopedia of Astronomy)




James Webb Space Telescope (NASA)

This animation shows the motions of bodies in the outer Solar System. Objects in long-term unstable orbits in this region are known as Centaurs. — European Southern Observatory

Animation of Orbits of Centaurs (European Southern Observatory)

Centaur Asteroids (Wolfram Alpha)

10199 Chariklo is the largest confirmed centaur (small body of the outer Solar System). It orbits the Sun between Saturn and Uranus, grazing the orbit of Uranus. On 26 March 2014, astronomers announced the discovery of two rings (nicknamed as the rivers Oiapoque and Chuí) around Chariklo by observing a stellar occultation, making it the first minor planet known to have rings. Chariklo was discovered by James V. Scotti of the Spacewatch program on February 15, 1997. Chariklo is named after the nymph Chariclo, the wife of Chiron and the daughter of Apollo. — Wikipedia

10199 Chariklo (Solar System Exploration, NASA)

Anton Petrov (WhatdaMath, YouTube Channel)
Cometary Activity Discovered on a Distant Centaur: A Nonaqueous Sublimation Mechanism (Colin Orion Chandler, et al., The Astrophysical Journal Letters)
PanSTARRS: C/2014 OG392 (Wikipedia)

Proposed Centaur mission could catch comets in the act of formation (David Dickinson, Universe Today via Phys.org)




2060 Chiron is a small Solar System body in the outer Solar System, orbiting the Sun between Saturn and Uranus. Discovered in 1977 by Charles Kowal, it was the first-identified member of a new class of objects now known as centaurs—bodies orbiting between the asteroid belt and the Kuiper belt. Although it was initially called an asteroid and classified only as a minor planet with the designation “2060 Chiron,” in 1989 it was found to exhibit behavior typical of a comet. Today it is classified as both a minor planet and a comet, and is accordingly also known by the cometary designation 95P/Chiron. Chiron is named after the centaur Chiron in Greek mythology — Wikipedia

Chiron (Encyclopædia Britannica)
Chiron (Eric Weisstein’s World of Astronomy, Wolfram Research)




Minor Planet Center (International Astronomical Union)


Centaur Mission (Phys.org)



Phys.org - latest science and technology news stories Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine.

  • China is considering a nuclear-powered mission to...
    on July 12, 2022 at 2:23 pm

    One look at the Planetary Decadal Survey for 2023–2032, and you will see some bold and cutting-edge mission proposals for the coming decade. Examples include a Uranus orbiter and probe (UOP) that would study Uranus' interior, atmosphere, magnetosphere, satellites, and rings; and an Enceladus orbiter and surface lander to study the active plumes emanating from Enceladus' southern polar region. Not to be outdone, China is also considering a nuclear-powered Neptune Explorer to explore the ice […]

  • Planetary Decadal Survey says it's time for a...
    on April 25, 2022 at 3:20 pm

    Since 2002, the United States National Research Council (NRC) has released a publication that identifies objectives and makes recommendations for science missions for NASA, the National Science Foundation, and other government agencies for the next decade. These reports, appropriately named Planetary Science Decadal Surveys, help inform future NASA missions that address the mysteries that persist in astronomy, astrophysics, earth science, and heliophysics.

  • NOAA's GOES-T reaches geostationary orbit, now...
    on March 15, 2022 at 9:52 am

    On March 14, 2022, GOES-T executed its final engine burn, placing the satellite in geostationary orbit 22,236 miles above Earth. Upon reaching this milestone, GOES-T was renamed GOES-18. GOES satellites are designated with a letter prior to launch and a number once they achieve geostationary orbit.

  • Students confirm errant rocket's Chinese origin,...
    on February 16, 2022 at 11:38 am

    The presumed SpaceX Falcon 9 rocket booster that's on a course to hit the moon March 4 is actually a Chinese booster from a rocket launch in 2014, a University of Arizona team has confirmed.

  • Scientists determine comet delivery to Moon
    on February 9, 2022 at 9:09 pm

    Southwest Research Institute scientists joined a team that reanalyzed and modeled data from a planned lunar impact more than a decade ago. The findings suggest that volatiles present in a crater near the Moon's south pole were likely delivered by a comet. Volatiles are chemical elements and compounds that can be readily vaporized and, in this case, were stabilized in ice lurking in this permanently shaded region.



Here are links to pages about closely related subjects.

Knowledge Realm


Law (Constant) Relativity
Force Gravity, Electromagnetism (Light, Color)
Matter (Microscope) Molecule, Atom (Periodic Table), Particle

Universe (Astronomical Instrument)
Galaxy Milky Way, Andromeda
Planetary System Star, Brown Dwarf, Planet, Moon

Our Neighborhood
Solar System Sun
Terrestrial Planet Mercury, Venus, Earth (Moon), Mars
Asteroid Belt Ceres, Vesta
Jovian Planet Jupiter, Saturn, Uranus, Neptune
Trans-Neptunian Object
Kuiper Belt Pluto, Haumea, Makemake
Scattered Disc Eris, Sedna, Planet X
Oort Cloud Etc. Scholz’s Star
Small Body Comet, Centaur, Asteroid


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