Key Facts
- Categorized as a Apollo-class Asteroid
- Comparable in size to the U.S. Capitol building
- Will pass within 19,854,309 km of Earth in 2026
- Classified as a Near Earth Asteroid (NEA)
- Classified as a Potentially Hazardous Asteroid (PHA)
- See orbit simulation
Overview
474158 (1999 FA) is a very small asteroid whose orbit crosses the orbit of Earth. NASA JPL has classified 1999 FA as a "Potentially Hazardous Asteroid" due to its predicted close pass(es) with Earth.
1999 FA orbits the sun every 409 days (1.12 years), coming as close as 0.93 AU and reaching as far as 1.22 AU from the sun. Based on its brightness and the way it reflects light, 1999 FA is probably between 0.125 to 0.561 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 FA has been observed. It completes a rotation on its axis every 10.09 hours.
1999 FA's spectral type None (Tholen) / S (SMASSII) indicates that it is likely to contain and .
Close Approaches
1999 FA's orbit is 0.00 AU from Earth's orbit at its closest point. This means that its orbit is relatively close to Earth's orbit.
1999 FA has 24 close approaches predicted in the coming decades:
| Date | Distance from Earth (km) | Velocity (km/s) |
|---|---|---|
| Sept. 12, 2026 | 19,854,309 | 6.522 |
| March 4, 2027 | 6,350,514 | 6.628 |
| Sept. 9, 2045 | 21,536,515 | 6.500 |
| March 5, 2046 | 2,975,187 | 6.851 |
| March 12, 2056 | 21,390,789 | 9.654 |
| Sept. 25, 2074 | 15,772,836 | 7.315 |
| Sept. 11, 2084 | 18,991,541 | 6.489 |
| March 2, 2085 | 8,137,369 | 6.545 |
| Sept. 2, 2094 | 25,183,786 | 6.463 |
| March 7, 2095 | 3,712,627 | 7.400 |
| Sept. 19, 2113 | 16,166,049 | 6.628 |
| March 1, 2114 | 15,352,830 | 6.404 |
| March 15, 2124 | 24,890,537 | 10.191 |
| Sept. 30, 2132 | 21,906,924 | 8.401 |
| Sept. 8, 2142 | 22,103,134 | 6.481 |
| March 6, 2143 | 1,885,472 | 6.944 |
| Sept. 15, 2152 | 16,705,572 | 6.534 |
| March 2, 2153 | 12,668,902 | 6.429 |
| Sept. 24, 2162 | 14,853,859 | 7.240 |
| Feb. 21, 2163 | 29,553,672 | 7.097 |
| Sept. 29, 2172 | 28,971,958 | 9.739 |
| March 15, 2184 | 24,906,964 | 10.186 |
| Sept. 1, 2193 | 25,134,443 | 6.456 |
| March 8, 2194 | 3,535,121 | 7.378 |
Images and Observations
1999 FA's orbit is determined by observations dating back to Oct. 10, 1978. It was last officially observed on Nov. 12, 2016. The IAU Minor Planet Center records 224 observations used to determine its orbit.
Accessibility and Exploration
1999 FA can be reached with a journey of 378 days. This trajectory would require a delta-v of 8.882 km/s. To put this into perspective, the delta-v to launch a rocket to Low-Earth Orbit is 9.7 km/s. There are 13,908 potential trajectories and launch windows to this asteroid.
See more at the NHATS Mission Trajectories table for 1999 FA.
Similar Objects
These objects have orbits that share similar characteristics to the orbit of 1999 FA:References
Search
or view a random objectOrbital Elements
- Epoch: 2460200.5 JD
- Semi-major axis: 1.078 AU
- Eccentricity: 0.1327
- Inclination: 12.03°
- Longitude of Ascending Node: 166.08°
- Argument of Periapsis: 296.99°
- Mean Anomaly: 13.09°
Physical Characteristics
- Diameter: ~0.343 km
- Magnitude: 20.71
- Spectral type (SMASS): S
Derived Characteristics
- Orbit Period: 409 days (1.12 years)
- Avg. Orbit Speed: 28.67 km/s
- Aphelion Distance: 1.22 AU
- Perihelion Distance: 0.93 AU
- Rotation Period: 10.09 hours
- Approx. Composition: and .
Map Comparison
Orbit Simulation
Sky Map
The position of 474158 (1999 FA) 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 FA 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.
