The largest asteroid predicted to pass by our planet in 2021 will be at its closest on March 21, providing astronomers a rare opportunity to get a good look at a rocky relic that formed at the dawn of our solar system.
Called 2001 FO32, the near-Earth asteroid will make its closest approach at a distance of about 1.25 million miles (2 million kilometers) – or 5 1/4 times the distance from Earth to the Moon. There is no threat of a collision with our planet now or for centuries to come.
“We know the orbital path of 2001 FO32 around the Sun very accurately, since it was discovered 20 years ago and has been tracked ever since,” said Paul Chodas, director of the Center for Near Earth Object Studies (CNEOS), which is managed by NASA’s Jet Propulsion Laboratory in Southern California. “There is no chance the asteroid will get any closer to Earth than 1.25 million miles.”
Still, that distance is close in astronomical terms, which is why 2001 FO32 has been designated a “potentially hazardous asteroid.” CNEOS computes high-precision orbits for near-Earth objects (NEOs) in support of NASA’s Planetary Defense Coordination Office, relying on telescopes and ground-based radar to help precisely characterize every NEO’s orbit to improve long-term hazard assessments.
During this approach, 2001 FO32 will pass by at about 77,000 mph (124,000 kph) – faster than the speed at which most asteroids encounter Earth. The reason for the asteroid’s unusually speedy close approach is its highly inclined and elongated (or eccentric) orbit around the Sun, an orbit that is tilted 39 degrees to Earth’s orbital plane. This orbit takes the asteroid closer to the Sun than Mercury and twice as far from the Sun as Mars.
As 2001 FO32 makes its inner solar system journey, the asteroid picks up speed like a skateboarder rolling down a halfpipe, and then slows after being flung back out into deep space and swinging back toward the Sun. It completes one orbit every 810 days (about 2 1/4 years).
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| This diagram depicts the elongated and inclined orbit of 2001 FO32 as it travels around the Sun (white ellipse). Because of this orbit, when the asteroid makes its close approach to Earth, it will be traveling at an unusually fast speed of 77,000 mph (124,000 kph). Credit: NASA/JPL-Caltech |
