Key Facts


Chiron is a large asteroid with an orbit between Jupiter and Neptune. NASA JPL has not classified Chiron as potentially hazardous because its orbit does not bring it close to Earth.

Chiron orbits the sun every 18,500 days (50.65 years), coming as close as 8.55 AU and reaching as far as 18.87 AU from the sun. Chiron is about 166.0 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the U.S. state of Massachusetts.

The rotation of Chiron has been observed. It completes a rotation on its axis every 5.92 hours.

Chiron's spectral type B (Tholen) / Cb (SMASSII) indicates that it is likely to contain water, iron, nickel, cobalt, nitrogen, and ammonia.

No Close Approaches

Chiron's orbit is 7.55 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

Chiron's orbit is determined by observations dating back to April 24, 1895. It was last officially observed on Jan. 31, 2023. The IAU Minor Planet Center records 4,045 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 Chiron:



   or view a random object

Orbital Elements

  • Epoch: 2460200.5 JD
  • Semi-major axis: 13.71 AU
  • Eccentricity: 0.3764
  • Inclination: 6.92°
  • Longitude of Ascending Node: 209.31°
  • Argument of Periapsis: 339.36°
  • Mean Anomaly: 196.94°

Physical Characteristics

  • Diameter: 166.00000 km
  • Magnitude: 5.64
  • Albedo: 0.15
  • Spectral type (Tholen): B
  • Spectral type (SMASS): Cb

Derived Characteristics

  • Orbit Period: 18,500 days (50.65 years)
  • Avg. Orbit Speed: 8.06 km/s
  • Aphelion Distance: 18.87 AU
  • Perihelion Distance: 8.55 AU
  • Rotation Period: 5.92 hours
  • Approx. Composition: water, iron, nickel, cobalt, nitrogen, and ammonia.

Map Comparison

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Orbit Simulation

Sky Map

The position of Chiron 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.