Key Facts


55637 (2002 UX25) is a dwarf planet whose orbit extends beyond the orbit of Neptune. NASA JPL has not classified 2002 UX25 as potentially hazardous because its orbit does not bring it close to Earth.

2002 UX25 orbits the sun every 101,000 days (276.52 years), coming as close as 36.65 AU and reaching as far as 48.49 AU from the sun. Based on its brightness and the way it reflects light, 2002 UX25 is probably between 483.676 to 1081.534 kilometers in diameter, making it one of the largest objects, very roughly comparable in size to Japan.

The rotation of 2002 UX25 has been observed. It completes a rotation on its axis every 14.38 hours.

No Close Approaches

2002 UX25's orbit is 35.70 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

2002 UX25's orbit is determined by observations dating back to Oct. 12, 1991. It was last officially observed on Nov. 13, 2020. The IAU Minor Planet Center records 465 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 2002 UX25:



   or view a random object

Orbital Elements

  • Epoch: 2459000.5 JD
  • Semi-major axis: 42.57 AU
  • Eccentricity: 0.139
  • Inclination: 19.44°
  • Longitude of Ascending Node: 204.62°
  • Argument of Periapsis: 277.67°
  • Mean Anomaly: 300.28°

Physical Characteristics

  • Diameter: ~624.424 km
  • Magnitude: 3.7

Derived Characteristics

  • Orbit Period: 101,000 days (276.52 years)
  • Avg. Orbit Speed: 4.59 km/s
  • Aphelion Distance: 48.49 AU
  • Perihelion Distance: 36.65 AU
  • Rotation Period: 14.38 hours

Map Comparison

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Orbit Simulation

Sky Map

The position of 55637 (2002 UX25) 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.