Kerberos (moon)
Kerberos (formerly known as S/2011 (134340) 1[3] and informally as P4) is a small moon of the dwarf planet Pluto. The satellite was discovered on 28 June 2011.[1] It is the fourth moon of Pluto to be discovered.[1][4] The others are Charon, discovered in 1978, Nix and Hydra, which were discovered in 2005, and Styx, discovered in 2012.[1]
.jpg) Kerberos as seen in 2015 by New Horizons | |
| Discovery | |
|---|---|
| Discovered by | Showalter M. R. and others[1] |
| Discovery date | June 28, 2011[1] (verified July 20, 2011)[2] |
| Orbital characteristics | |
| Satellite of | Pluto[1] |
Discovery
The moon was discovered by a Hubble Space Telescope observing team led by Mark Showalter,[2] while they were trying to find out if Pluto had any rings.[1] Kerberos was first seen in a photo taken with Hubble's Wide Field Camera 3, on June 28, 2011.[1][3] More photos were taken on July 3 and July 18,[1][3] 2011, to confirm that it exists.[1] The moon was officially verified and announced on July 20, 2011.[2][4] Kerberos was not seen in earlier Hubble photos because the exposure times were shorter.[1] The moon may have appeared as a very faint smudge in photos taken in 2006,[1][3] but was ignored because it was not clear.[1] Kerberos is possibly also visible in images taken in 2010.[3] The New Horizons space probe took pictures of Kerberos and Pluto's other moons in 2015.
Structure
Originally, scientists estimated that Kerberos had a diameter of 13–34 kilometres (8.1–21.1 mi).[1][2][5][6] Later, scientists found out that Kerberos is not round, and has two "lobes", or large round parts. The bigger lobe is about 8 kilometres (5.0 mi) across, and the smaller one is about 5 kilometres (3.1 mi) across. Because of its shape, scientists think that Kerberos could have been created when two smaller objects combined together.[7] Because of how the surface of Kerberos reflects light, scientists believe that the surface of Kerberos is covered in water ice.[7]
Kerberos and Pluto's other moons are thought to have been created by a cosmic collision between the dwarf planet and another celestial body early in the Solar System's history.[8]
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 "NASA's Hubble Discovers Another Moon Around Pluto". NASA. 2011-07-20. Retrieved 2011-08-01.
- ↑ 2.0 2.1 2.2 2.3 "Fourth Moon Adds to Pluto's Appeal". Archived from the original on 2015-05-01. Retrieved 2011-08-01.
- ↑ 3.0 3.1 3.2 3.3 3.4 Green, Daniel W.E (2011-07-20). "NEW SATELLITE OF (134340) PLUTO: S/2011 (134340) 1". Central Bureau for Astronomical Telegrams. Retrieved 2011-08-01.
- ↑ 4.0 4.1 Wall, Mike (2011-07-20). "New Pluto Moon Foreshadows More Surprises for NASA Probe En Route". space.com. Retrieved 2011-08-01.
- ↑ "Welcome to the solar system, P4", New Scientist, Reed Business Information, no. 2823, p. 14, 2011-07-30
- ↑ Harvey, Samantha (2011-07-20). "Solar System Exploration: Planets: Dwarf Planets: Pluto: Read More". NASA. Archived from the original on 2013-02-02. Retrieved 2011-08-01.
- ↑ 7.0 7.1 "Kerberos". NASA. Retrieved 2025-11-15.
- ↑ Boyle, Alan (2011-07-20). "Scientists spot Pluto's fourth moon". msnbc.com. Archived from the original on 2012-07-15. Retrieved 2011-08-01.