Key Facts

  • Categorized as a Jupiter Trojan
  • Comparable in size to the U.S. state of Rhode Island (65.92 km diameter)
  • Not a Near Earth Object
  • Not a Potentially Hazardous Object
  • See orbit simulation


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

Palamedes orbits the sun every 4,240 days (11.61 years), coming as close as 4.75 AU and reaching as far as 5.51 AU from the sun. Palamedes is about 65.9 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the U.S. state of Rhode Island.

The rotation of Palamedes has been observed. It completes a rotation on its axis every 7.24 days.

No Close Approaches

Palamedes's orbit is 3.80 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

Palamedes's orbit is determined by observations dating back to Feb. 15, 1953. It was last officially observed on Jan. 6, 2020. The IAU Minor Planet Center records 1,651 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 Palamedes:



   or view a random object

Orbital Elements

  • Epoch: 2459000.5 JD
  • Semi-major axis: 5.129 AU
  • Eccentricity: 0.0747
  • Inclination: 13.91°
  • Longitude of Ascending Node: 327.36°
  • Argument of Periapsis: 94.88°
  • Mean Anomaly: 294.21°

Physical Characteristics

  • Diameter: 65.91600 km
  • Magnitude: 9.2
  • Albedo: 0.071

Derived Characteristics

  • Orbit Period: 4,240 days (11.61 years)
  • Avg. Orbit Speed: 13.16 km/s
  • Aphelion Distance: 5.51 AU
  • Perihelion Distance: 4.75 AU
  • Rotation Period: 7.24 days

Size Comparison

Orbit Simulation

Sky Map

The position of Palamedes 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.