Phaethon is a mid-sized asteroid whose orbit crosses the orbit of Earth. NASA JPL has classified Phaethon as a "Potentially Hazardous Asteroid" due to its predicted close pass(es) with Earth.
Phaethon orbits the sun every 524 days (1.43 years), coming as close as 0.14 AU and reaching as far as 2.40 AU from the sun. Its orbit is highly elliptical. Phaethon is about 6.3 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the San Francisco Bay.
The rotation of Phaethon has been observed. It completes a rotation on its axis every 3.60 days.
Phaethon's spectral type F (Tholen) / B (SMASSII) indicates that it is likely to contain iron, hydrogen, ammonia, and nitrogen.
Phaethon's orbit is 0.02 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.
Phaethon has 9 close approaches predicted in the coming decades:
| Date | Distance from Earth (km) | Velocity (km/s) |
|---|---|---|
| Dec. 11, 2050 | 12,353,199 | 36.236 |
| Dec. 18, 2060 | 16,624,048 | 30.648 |
| Dec. 14, 2093 | 2,965,449 | 34.235 |
| Dec. 22, 2103 | 25,661,392 | 29.015 |
| Dec. 13, 2136 | 8,237,414 | 35.401 |
| Dec. 19, 2146 | 13,502,098 | 31.170 |
| Dec. 9, 2179 | 28,507,613 | 39.646 |
| Dec. 15, 2189 | 5,308,404 | 34.795 |
| Dec. 20, 2199 | 14,196,180 | 31.016 |
Phaethon's orbit is determined by observations dating back to Oct. 27, 1983. It was last officially observed on Nov. 5, 2019. The IAU Minor Planet Center records 4,362 observations used to determine its orbit.
Scientists have been able to determine this object's shape.
View asteroid Phaethon in 3D.
The position of Phaethon 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.