Key Facts

  • Categorized as a Amor-class Asteroid
  • Comparable in size to the city of Philadelphia (16.84 km diameter)
  • Classified as a Near Earth Asteroid (NEA)
  • Not a Potentially Hazardous Object
  • See orbit simulation


Eros is a large asteroid whose orbit approaches the orbit of Earth but does not cross it. NASA JPL has classified Eros as a "Near Earth Asteroid" due to its orbit's proximity to Earth, but it is not considered potentially hazardous because computer simulations have not indicated any imminent likelihood of future collision.

Eros orbits the sun every 643 days (1.76 years), coming as close as 1.13 AU and reaching as far as 1.78 AU from the sun. Eros is about 16.8 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the city of Philadelphia.

The rotation of Eros has been observed. It completes a rotation on its axis every 5.27 days.

Eros's spectral type S (Tholen) / S (SMASSII) indicates that it is likely to contain magnesium silicate and iron silicate.

No Close Approaches

Eros's orbit is 0.15 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

Eros's orbit is determined by observations dating back to Oct. 29, 1893. It was last officially observed on Feb. 13, 2019. The IAU Minor Planet Center records 8,146 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 Eros:



   or view a random object

Orbital Elements

  • Epoch: 2459000.5 JD
  • Semi-major axis: 1.458 AU
  • Eccentricity: 0.223
  • Inclination: 10.83°
  • Longitude of Ascending Node: 304.3°
  • Argument of Periapsis: 178.88°
  • Mean Anomaly: 271.07°

Physical Characteristics

  • Diameter: 16.84000 km
  • Magnitude: 10.4
  • Albedo: 0.25
  • Spectral type (Tholen): S
  • Spectral type (SMASS): S

Derived Characteristics

  • Orbit Period: 643 days (1.76 years)
  • Avg. Orbit Speed: 24.67 km/s
  • Aphelion Distance: 1.78 AU
  • Perihelion Distance: 1.13 AU
  • Rotation Period: 5.27 hours
  • Approx. Composition: magnesium silicate and iron silicate.

Map Comparison

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Orbit Simulation

Sky Map

The position of Eros 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.