Key Facts


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

James Bradley orbits the sun every 2,350 days (6.43 years), coming as close as 3.28 AU and reaching as far as 3.63 AU from the sun. James Bradley is about 33.7 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the city of New York.

The rotation of James Bradley has been observed. It completes a rotation on its axis every 16.28 hours.

No Close Approaches

James Bradley's orbit is 2.30 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

James Bradley's orbit is determined by observations dating back to Feb. 9, 1905. It was last officially observed on July 2, 2023. The IAU Minor Planet Center records 4,190 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 James Bradley:



   or view a random object

Orbital Elements

  • Epoch: 2460200.5 JD
  • Semi-major axis: 3.455 AU
  • Eccentricity: 0.0495
  • Inclination: 6.42°
  • Longitude of Ascending Node: 133.34°
  • Argument of Periapsis: 332.11°
  • Mean Anomaly: 200.32°

Physical Characteristics

  • Diameter: 33.72600 km
  • Magnitude: 10.67
  • Albedo: 0.107

Derived Characteristics

  • Orbit Period: 2,350 days (6.43 years)
  • Avg. Orbit Speed: 15.99 km/s
  • Aphelion Distance: 3.63 AU
  • Perihelion Distance: 3.28 AU
  • Rotation Period: 16.28 hours

Map Comparison

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Orbit Simulation

Sky Map

The position of James Bradley 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.