Key Facts

  • Categorized as a Jupiter Trojan
  • Comparable in size to the U.S. state of Delaware (108.84 km diameter)
  • Not a Near Earth Object
  • Not a Potentially Hazardous Object
  • See orbit simulation


Antilochus is a large asteroid that shares Jupiter's orbit around the sun. NASA JPL has not classified Antilochus as potentially hazardous because its orbit does not bring it close to Earth.

Antilochus orbits the sun every 4,260 days (11.66 years), coming as close as 4.87 AU and reaching as far as 5.42 AU from the sun. Antilochus is about 108.8 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the U.S. state of Delaware.

The rotation of Antilochus has been observed. It completes a rotation on its axis every 15.76 hours.

Antilochus's spectral type D (Tholen) / None (SMASSII) indicates that it is likely to contain .

No Close Approaches

Antilochus's orbit is 3.88 AU from Earth's orbit at its closest point. This means that there is an extremely wide berth between this asteroid and Earth at all times.

Orbital simulations conducted by NASA JPL's CNEOS do not show any close approaches to Earth.

Images and Observations

Antilochus's orbit is determined by observations dating back to Nov. 10, 1926. It was last officially observed on May 8, 2023. The IAU Minor Planet Center records 4,129 observations used to determine its orbit.

Accessibility and Exploration

This asteroid is not considered a viable target for human exploration by the NHATS study.

Similar Objects

These objects have orbits that share similar characteristics to the orbit of Antilochus:



   or view a random object

Orbital Elements

  • Epoch: 2460200.5 JD
  • Semi-major axis: 5.145 AU
  • Eccentricity: 0.054
  • Inclination: 28.49°
  • Longitude of Ascending Node: 221.37°
  • Argument of Periapsis: 187.89°
  • Mean Anomaly: 65.8°

Physical Characteristics

  • Diameter: 108.84200 km
  • Magnitude: 8.58
  • Albedo: 0.054
  • Spectral type (Tholen): D

Derived Characteristics

  • Orbit Period: 4,260 days (11.66 years)
  • Avg. Orbit Speed: 13.14 km/s
  • Aphelion Distance: 5.42 AU
  • Perihelion Distance: 4.87 AU
  • Rotation Period: 15.76 hours
  • Approx. Composition: .

Map Comparison

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Orbit Simulation

Sky Map

The position of Antilochus is indicated by a ◯ pink circle. Note that the object may not be in your current field of view. Use the controls below to adjust position, location, and time.