This weekend will see the largest asteroid predicted to pass by our planet in 2021 make its closest approach. It comes just weeks after the passing of an asteroid nicknamed the ‘God Of Chaos’— and NASA’s telescopes will be checking it out.
Classed as “potentially hazardous” by astronomers and moving spectacularly fast, the 0.6 mile/1 kilometer wide 2001 FO32 will be at its closest to Earth on March 21, 2021.
It will pass within 1.25 million miles/2 million kilometers according to NASA’s Jet Propulsion Laboratory.
That might not sound too close, but that distance is close enough—in astronomical terms—for 2001 FO32 to be classed as “potentially hazardous.” Besides, its arrival in the vicinity of Earth is a very special occasion for astronomers. Despite it passing about five times further than the Moon is from Earth, 2001 FO32’s relatively close approach will make it bright enough for astronomers to study it in detail.
While early March’s Asteroid Apophis streaked by Earth at 19 miles/30 km per second, 2001 FO32 will be moving at an astonishing 77,000 mph/124,000 kph.
That’s much faster than most asteroids travel.
Its terrific speeds are the result of its highly eccentric and elliptical orbital path around the Sun, which is highly inclined to Earth and takes it closer to the Sun than Mercury and twice as far from the Sun as Mars.
Each time it enters the inner Solar System to round the Sun it picks up speed, slowing down as it travels in the opposite direction.
Little is known about the nature of 2001 FO32 other than that it represents a relic of the formation of our Solar System.
As such, the arrival of 2001 FO32 is a rare opportunity for astronomers to use large telescopes to get a closer look at something incredibly ancient. So this weekend, 2001 FO32’s infrared spectrum will be measured by a 10.5-foot/3.2-meter telescope at NASA’s Infrared Telescope Facility on top of Hawaii’s Mauna Kea.
That’s important because recent studies by NEOWISE (who last year discovered “comet of the century” Comet NEOWISE that was visible in July) suggests that 2001 FO32 is faint in the infrared, so may be smaller than previously thought.
Astronomers will also be trying to determine what 2001 FO32 is made of—and whether it has a moon in orbit.
“Observations dating back 20 years revealed that about 15% of near-Earth asteroids comparable in size to 2001 FO32 have a small moon,” said Lance Benner, principal scientist at JPL. “Currently little is known about this object, so the very close encounter provides an outstanding opportunity to learn a great deal about this asteroid.”
That’s true of a binary asteroid called Didymos and Didymoon that will pass close to Earth in October 2022. The Double Asteroid Redirection Test (DART), a mission from NASA and the European Space Agency (ESA), will launch later this year and crash into the moon, using “kinetic deflection” to slightly change the trajectory of both asteroids.
Discovered in March 2001 by the Lincoln Near-Earth Asteroid Research (LINEAR) program in Socorro, New Mexico, 2001 FO32’s exact orbit has been calculated in detail. That’s why astronomers know that it won’t get any closer to Earth than 1.25 million miles this weekend—and not will it threaten Earth for the remainder of the 21st century.
Asteroid 2001 FO32’s next trip to Earth’s neighbourhood will be in 2052 when it will pass by at about seven lunar distances, or 1.75 million miles (2.8 million kilometers).
Wishing you clear skies and wide eyes.