Key Facts
- Categorized as a Apollo-class Asteroid
- Comparable in size to the San Francisco Bay (5.70 km diameter)
- Will pass within 26,603,572 km of Earth in 2064
- Classified as a Near Earth Asteroid (NEA)
- Not a Potentially Hazardous Object
- See orbit simulation
Overview
Hephaistos is a mid-sized asteroid whose orbit crosses the orbit of Earth. NASA JPL has classified Hephaistos 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.
Hephaistos orbits the sun every 1,160 days (3.18 years), coming as close as 0.35 AU and reaching as far as 3.97 AU from the sun. Its orbit is highly elliptical. Hephaistos is about 5.7 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the San Francisco Bay.
The rotation of Hephaistos has been observed. It completes a rotation on its axis every 48.00 hours.
Close Approaches
Hephaistos's orbit is 0.12 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.
Hephaistos has 7 close approaches predicted in the coming decades:
| Date | Distance from Earth (km) | Velocity (km/s) |
|---|---|---|
| Sept. 23, 2064 | 26,603,572 | 33.859 |
| Jan. 21, 2074 | 29,574,306 | 31.827 |
| Sept. 19, 2115 | 13,376,989 | 30.322 |
| Jan. 24, 2125 | 25,352,389 | 30.487 |
| Sept. 10, 2131 | 29,506,533 | 24.055 |
| Sept. 23, 2166 | 17,689,882 | 32.232 |
| Jan. 28, 2176 | 22,629,429 | 28.803 |
Images and Observations
Hephaistos's orbit is determined by observations dating back to Sept. 27, 1978. It was last officially observed on Aug. 5, 2023. The IAU Minor Planet Center records 3,471 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 Hephaistos:References
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or view a random objectOrbital Elements
- Epoch: 2460200.5 JD
- Semi-major axis: 2.161 AU
- Eccentricity: 0.8374
- Inclination: 11.54°
- Longitude of Ascending Node: 27.5°
- Argument of Periapsis: 209.43°
- Mean Anomaly: 61.58°
Physical Characteristics
- Diameter: 5.70000 km
- Magnitude: 13.52
- Albedo: 0.163
- Spectral type (Tholen): SG
Derived Characteristics
- Orbit Period: 1,160 days (3.18 years)
- Avg. Orbit Speed: 20.27 km/s
- Aphelion Distance: 3.97 AU
- Perihelion Distance: 0.35 AU
- Rotation Period: 48.00 hours
Map Comparison
Orbit Simulation
Sky Map
The position of Hephaistos 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 Hephaistos 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.
