Key Facts

  • Categorized as a Jupiter Trojan
  • Comparable in size to the U.S. state of Connecticut (126.29 km diameter)
  • Not a Near Earth Object
  • Not a Potentially Hazardous Object
  • See orbit simulation


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

Mentor orbits the sun every 4,270 days (11.69 years), coming as close as 4.78 AU and reaching as far as 5.51 AU from the sun. Mentor is about 126.3 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the U.S. state of Connecticut.

The rotation of Mentor has been observed. It completes a rotation on its axis every 7.70 days.

Mentor's spectral type None (Tholen) / X (SMASSII) indicates that it is likely to contain nickel, iron, and cobalt.

No Close Approaches

Mentor's orbit is 3.82 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

Mentor's orbit is determined by observations dating back to March 14, 1983. It was last officially observed on Feb. 3, 2020. The IAU Minor Planet Center records 2,382 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 Mentor:



   or view a random object

Orbital Elements

  • Epoch: 2459000.5 JD
  • Semi-major axis: 5.147 AU
  • Eccentricity: 0.0704
  • Inclination: 24.63°
  • Longitude of Ascending Node: 179.62°
  • Argument of Periapsis: 130.16°
  • Mean Anomaly: 305.52°

Physical Characteristics

  • Diameter: 126.28800 km
  • Magnitude: 8.4
  • Albedo: 0.044
  • Spectral type (SMASS): X

Derived Characteristics

  • Orbit Period: 4,270 days (11.69 years)
  • Avg. Orbit Speed: 13.11 km/s
  • Aphelion Distance: 5.51 AU
  • Perihelion Distance: 4.78 AU
  • Rotation Period: 7.70 days
  • Approx. Composition: nickel, iron, and cobalt.

Size Comparison

Orbit Simulation

Sky Map

The position of Mentor 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.