2021 SD2 is a very small asteroid whose orbit crosses the orbit of Earth. NASA JPL has classified 2021 SD2 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.
2021 SD2 orbits the sun every 455 days (1.25 years), coming as close as 0.86 AU and reaching as far as 1.46 AU from the sun. Based on its brightness and the way it reflects light, 2021 SD2 is probably between 0.007 to 0.032 kilometers in diameter, making it a small to average asteroid, very roughly comparable in size to a school bus or smaller.
2021 SD2's orbit is 0.01 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.
2021 SD2 has 4 close approaches predicted in the coming decades:
| Date | Distance from Earth (km) | Velocity (km/s) |
|---|---|---|
| Oct. 7, 2021 | 2,201,063 | 6.619 |
| Sept. 29, 2026 | 15,747,079 | 9.884 |
| March 8, 2058 | 22,167,699 | 11.206 |
| Feb. 28, 2063 | 5,293,815 | 7.799 |
2021 SD2's orbit is determined by observations dating back to Sept. 29, 2021. It was last officially observed on Oct. 7, 2021. The IAU Minor Planet Center records 26 observations used to determine its orbit.
2021 SD2 can be reached with a journey of 346 days. This trajectory would require a delta-v of 7.256 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 53,571 potential trajectories and launch windows to this asteroid.
See more at the NHATS Mission Trajectories table for 2021 SD2.
The position of 2021 SD2 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.