Key Facts


Herodotus is a large asteroid that orbits between Mars and Jupiter in the outer reaches of the main asteroid belt. NASA JPL has not classified Herodotus as potentially hazardous because its orbit does not bring it close to Earth.

Herodotus orbits the sun every 2,430 days (6.65 years), coming as close as 3.13 AU and reaching as far as 3.94 AU from the sun. Herodotus is about 30.3 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the city of Indianapolis.

The rotation of Herodotus has been observed. It completes a rotation on its axis every 38.94 hours.

No Close Approaches

Herodotus's orbit is 2.13 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

Herodotus's orbit is determined by observations dating back to Sept. 24, 1960. It was last officially observed on July 17, 2021. The IAU Minor Planet Center records 3,720 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 Herodotus:



   or view a random object

Orbital Elements

  • Epoch: 2459396.5 JD
  • Semi-major axis: 3.536 AU
  • Eccentricity: 0.1144
  • Inclination: 10.83°
  • Longitude of Ascending Node: 7.96°
  • Argument of Periapsis: 9.1°
  • Mean Anomaly: 28.51°

Physical Characteristics

  • Diameter: 30.34600 km
  • Magnitude: 11.41
  • Albedo: 0.076

Derived Characteristics

  • Orbit Period: 2,430 days (6.65 years)
  • Avg. Orbit Speed: 15.83 km/s
  • Aphelion Distance: 3.94 AU
  • Perihelion Distance: 3.13 AU
  • Rotation Period: 38.94 hours

Map Comparison

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Orbit Simulation

Sky Map

The position of Herodotus 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.