Key Facts

  • Categorized as a Amor-class Asteroid
  • Comparable in size to the U.S. Capitol building
  • Classified as a Near Earth Asteroid (NEA)
  • Classified as a Potentially Hazardous Asteroid (PHA)
  • See orbit simulation


38071 (1999 GU3) is a very small asteroid whose orbit approaches the orbit of Earth but does not cross it. NASA JPL has classified 1999 GU3 as a "Potentially Hazardous Asteroid" due to its predicted close pass(es) with Earth.

1999 GU3 orbits the sun every 1,100 days (3.01 years), coming as close as 1.03 AU and reaching as far as 3.15 AU from the sun. Based on its brightness and the way it reflects light, 1999 GU3 is probably between 0.338 to 0.755 kilometers in diameter, making it larger than 90% of asteroids but tiny compared to large asteroids, very roughly comparable in size to the U.S. Capitol building.

The rotation of 1999 GU3 has been observed. It completes a rotation on its axis every 216.00 hours.

No Close Approaches

1999 GU3's orbit is 0.03 AU from Earth's orbit at its closest point. This means that there is an 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

1999 GU3's orbit is determined by observations dating back to April 10, 1999. It was last officially observed on Feb. 16, 2020. The IAU Minor Planet Center records 464 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 1999 GU3:



   or view a random object

Orbital Elements

  • Epoch: 2459396.5 JD
  • Semi-major axis: 2.09 AU
  • Eccentricity: 0.507
  • Inclination: 12.73°
  • Longitude of Ascending Node: 195.49°
  • Argument of Periapsis: 8.84°
  • Mean Anomaly: 129.07°

Physical Characteristics

  • Diameter: ~0.436 km
  • Magnitude: 19.48

Derived Characteristics

  • Orbit Period: 1,100 days (3.01 years)
  • Avg. Orbit Speed: 20.67 km/s
  • Aphelion Distance: 3.15 AU
  • Perihelion Distance: 1.03 AU
  • Rotation Period: 216.00 hours

Map Comparison

Click to load map

Orbit Simulation

Sky Map

The position of 38071 (1999 GU3) 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.

Size Rendering

The below comparison is an artistic rendering that uses available data on the diameter of 1999 GU3 to create an approximate landscape rendering with New York City in the background. This approximation is built for full-resolution desktop browsers. Shape, color, and texture of asteroid are imagined.