(60621) 2000 FE8
A resonant binary trans-Neptunian object in a 2:5 Neptune resonance.
(60621) 2000 FE8 is a binary object in the outer Solar System, about 146 kilometers across. It was discovered on March 27, 2000, by astronomers J.J. Kavelaars, Brett Gladman, Jean-Marc Petit, and Matthew Holman at the Mauna Kea Observatory in Hawaii. The object follows a highly eccentric orbit that cuts across the paths of almost all dwarf planets and dwarf planet candidates, shifting its position between the Kuiper belt and the scattered disc.
It belongs to a group of trans-Neptunian objects in a 2:5 orbital resonance with Neptune: for every five orbits Neptune completes, 2000 FE8 makes two. The largest known object in this same resonance is (84522) 2002 TC302.
In January 2007, the Hubble Space Telescope discovered a moon orbiting 2000 FE8. The satellite is about 115 kilometers in diameter—roughly 75.7% the size of the primary—and orbits at a distance of 1,180 kilometers, completing one revolution every seven days.
The Minor Planet Center assigned the number (60621) to this object on June 14, 2003. As of 2025, it has not received a name.
Quick Facts
- Minorplanet
- yes
- Background
- #C2E0FF
- Discoverer
- J. Kavelaars / B. Gladman / J.-M. Petit / M. Holman
- Discovery Site
- Mauna Kea Obs.
- Discovered
- 27 March 2000
- Mpc Name
- (60621) 2000 FE · 8
- Mp Category
- TNOres 2:5
- Epoch
- 4 September 2017 (JD 2458000.5)
- Uncertainty
- 4
- Observation Arc
- 6.80 yr (2,485 days)
- Aphelion
- 78.590 AU
- Perihelion
- 33.185 AU
Facts from the source article.
Lore & Background
2000 FE8 was discovered on 27 March 2000 by astronomers JJ Kavelaars, Brett Gladman, Jean-Marc Petit and Matthew Holman at Mauna Kea Observatory on Hawaii. It resides in an eccentric orbit and is locked in a 2:5 orbital resonance with Neptune, meaning that for every five orbits Neptune completes, 2000 FE8 makes only two. Its orbit alternates between the Kuiper belt and the scattered disc.
The object has a satellite, discovered by the Hubble Space Telescope in January 2007, seven years after 2000 FE8 itself was found. The moon orbits at 1180 kilometers away from the primary, completing one orbit in approximately 7 days. It is thought to be 115 km in diameter, just 75.7% the diameter of 2000 FE8 itself.
This minor planet was numbered by the Minor Planet Center on 14 June 2003. As of 2025, it has not been named.
Reader's Guide
2000 FE8 is significant as a resonant trans-Neptunian object locked in a 2:5 orbital resonance with Neptune, a dynamical state shared by several other objects including the larger (84522) 2002 TC302. Its extremely eccentric orbit crosses the paths of many other trans-Neptunian objects, including almost all dwarf planets and dwarf planet candidates, causing its position to alternate between the Kuiper belt and the scattered disc. The presence of a binary companion, discovered by the Hubble Space Telescope in 2007, adds to its scientific interest, as binary systems in the outer Solar System provide insights into formation and dynamical evolution. The satellite, approximately 115 km in diameter, orbits at 1180 km from the primary with a period of about 7 days. The object was numbered in 2003 but remains unnamed as of 2025, reflecting the ongoing cataloging of distant minor planets.
Did You Know?
- 2000 FE8 is approximately 146 kilometers in diameter.
- It was discovered on 27 March 2000 at Mauna Kea Observatory.
- The moon orbits at 1180 kilometers from 2000 FE8, completing one orbit in about 7 days.
More in Trans-Neptunian Objects 1-24
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