Key Facts

  • Categorized as a Amor-class Asteroid
  • Comparable in size to the island of Manhattan (3.50 km diameter)
  • Classified as a Near Earth Asteroid (NEA)
  • Not a Potentially Hazardous Object
  • See orbit simulation


Boreas is a mid-sized asteroid whose orbit approaches the orbit of Earth but does not cross it. NASA JPL has classified Boreas 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.

Boreas orbits the sun every 1,250 days (3.42 years), coming as close as 1.25 AU and reaching as far as 3.29 AU from the sun. Boreas is about 3.5 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the island of Manhattan.

The rotation of Boreas has been observed. It completes a rotation on its axis every 3.47 hours.

Boreas's spectral type S (Tholen) / S (SMASSII) indicates that it is likely to contain and .

No Close Approaches

Boreas's orbit is 0.25 AU from Earth's orbit at its closest point. This means that there is a 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

Boreas's orbit is determined by observations dating back to Sept. 1, 1953. It was last officially observed on June 9, 2021. The IAU Minor Planet Center records 1,759 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 Boreas:



   or view a random object

Orbital Elements

  • Epoch: 2459600.5 JD
  • Semi-major axis: 2.272 AU
  • Eccentricity: 0.4498
  • Inclination: 12.88°
  • Longitude of Ascending Node: 340.6°
  • Argument of Periapsis: 335.92°
  • Mean Anomaly: 352.24°

Physical Characteristics

  • Diameter: 3.50000 km
  • Magnitude: 14.88
  • Spectral type (Tholen): S
  • Spectral type (SMASS): S

Derived Characteristics

  • Orbit Period: 1,250 days (3.42 years)
  • Avg. Orbit Speed: 19.77 km/s
  • Aphelion Distance: 3.29 AU
  • Perihelion Distance: 1.25 AU
  • Rotation Period: 3.47 hours
  • Approx. Composition: and .

Map Comparison

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Orbit Simulation

Sky Map

The position of Boreas 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 above comparison is an artistic rendering that uses available data on the diameter of Boreas to create an approximate landscape rendering with Mount Everest in the background. This approximation is built for full-resolution desktop browsers. Shape, color, and texture of asteroid are imagined.