Key Facts

  • Categorized as a Jupiter Trojan
  • Comparable in size to the U.S. state of Rhode Island (45.68 km diameter)
  • Not a Near Earth Object
  • Not a Potentially Hazardous Object
  • See orbit simulation


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

Demophon orbits the sun every 4,400 days (12.05 years), coming as close as 4.63 AU and reaching as far as 5.89 AU from the sun. Demophon is about 45.7 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the U.S. state of Rhode Island.

The rotation of Demophon has been observed. It completes a rotation on its axis every 29.82 days.

No Close Approaches

Demophon's orbit is 3.65 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

Demophon's orbit is determined by observations dating back to Sept. 22, 1985. It was last officially observed on Oct. 31, 2019. The IAU Minor Planet Center records 1,615 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 Demophon:



   or view a random object

Orbital Elements

  • Epoch: 2459000.5 JD
  • Semi-major axis: 5.257 AU
  • Eccentricity: 0.1195
  • Inclination: 2.87°
  • Longitude of Ascending Node: 24.3°
  • Argument of Periapsis: 59.01°
  • Mean Anomaly: 263.0°

Physical Characteristics

  • Diameter: 45.68300 km
  • Magnitude: 10.1
  • Albedo: 0.077

Derived Characteristics

  • Orbit Period: 4,400 days (12.05 years)
  • Avg. Orbit Speed: 13.00 km/s
  • Aphelion Distance: 5.89 AU
  • Perihelion Distance: 4.63 AU
  • Rotation Period: 29.82 days

Size Comparison

Orbit Simulation

Sky Map

The position of Demophon 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.