Kerberos

satellite of Pluto

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July 20, 2026

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Kerberos is one of Pluto's five known moons. It was discovered in 2011 using the Hubble Space Telescope. Kerberos is much smaller than Pluto's largest moon, Charon, and is named after the mythological dog that guards the entrance to the underworld in Greek mythology. For every orbit Charon completes, Kerberos completes about one-fifth of an orbit.123

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Christening Pluto’s Moons
Kerberos
Kerberos is another spelling of the more-familiar Cerberus (that spelling also was already assigned to an asteroid). We would probably agree that either one is much more colourful than "P4," the moon’s provisional name after its discovery in 2011. Kerberos is the dog who…
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Kerberos is another spelling of the more-familiar Cerberus (that spelling also was already assigned to an asteroid). We would probably agree that either one is much more colourful than "P4," the moon’s provisional name after its discovery in 2011. Kerberos is the dog who…
Read More

Pluto
Pluto’s moons
other four moons—Hydra, Nix, Kerberos, and Styx—are much smaller than Charon. All four are elongated. They revolve around Pluto outside Charon’s path in nearly circular orbits (like Charon) and in the same orbital plane as Charon. The orbital radius of Hydra is about 64,721 km (40,216 miles); that of…
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other four moons—Hydra, Nix, Kerberos, and Styx—are much smaller than Charon. All four are elongated. They revolve around Pluto outside Charon’s path in nearly circular orbits (like Charon) and in the same orbital plane as Charon. The orbital radius of Hydra is about 64,721 km (40,216 miles); that of…
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Pluto
Discoveries of Pluto and its moons
…astronomers discovered the small moon Kerberos in images made with the HST. As with the discovery of Nix and Hydra, the astronomers checked earlier Hubble images and found faint traces of what appeared to be Kerberos in images from 2006 and 2010. The HST was used again in 2012 to…
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…astronomers discovered the small moon Kerberos in images made with the HST. As with the discovery of Nix and Hydra, the astronomers checked earlier Hubble images and found faint traces of what appeared to be Kerberos in images from 2006 and 2010. The HST was used again in 2012 to…
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New Horizons
smaller moons of Pluto—Styx, Nix, Kerberos, and Hydra—were found to be spinning very rapidly, unlike most other satellites in the solar system, which keep one side facing the planet they orbit.
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smaller moons of Pluto—Styx, Nix, Kerberos, and Hydra—were found to be spinning very rapidly, unlike most other satellites in the solar system, which keep one side facing the planet they orbit.
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