Key Facts


Lachesis is a large asteroid orbiting between Mars and Jupiter in the main portion of the asteroid belt. NASA JPL has not classified Lachesis as potentially hazardous because its orbit does not bring it close to Earth.

Lachesis orbits the sun every 2,020 days (5.53 years), coming as close as 2.97 AU and reaching as far as 3.28 AU from the sun. Lachesis is about 155.1 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the U.S. state of Vermont.

The rotation of Lachesis has been observed. It completes a rotation on its axis every 46.55 hours.

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

No Close Approaches

Lachesis's orbit is 1.97 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

Lachesis's orbit is determined by observations dating back to April 25, 1872. It was last officially observed on July 4, 2023. The IAU Minor Planet Center records 4,752 observations used to determine its orbit.

Scientists have been able to determine this object's shape:

View asteroid Lachesis in 3D.

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 Lachesis:



   or view a random object

Orbital Elements

  • Epoch: 2460200.5 JD
  • Semi-major axis: 3.124 AU
  • Eccentricity: 0.0501
  • Inclination: 6.95°
  • Longitude of Ascending Node: 341.13°
  • Argument of Periapsis: 236.57°
  • Mean Anomaly: 157.75°

Physical Characteristics

  • Diameter: 155.13200 km
  • Magnitude: 7.88
  • Albedo: 0.058
  • Spectral type (Tholen): C
  • Spectral type (SMASS): C

Derived Characteristics

  • Orbit Period: 2,020 days (5.53 years)
  • Avg. Orbit Speed: 16.82 km/s
  • Aphelion Distance: 3.28 AU
  • Perihelion Distance: 2.97 AU
  • Rotation Period: 46.55 hours
  • Approx. Composition: water, iron, nickel, cobalt, nitrogen, and ammonia.

Map Comparison

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Orbit Simulation

Sky Map

The position of Lachesis 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.