The jig may be up for an “asteroid” that’s expected to get nabbed by Earth’s gravity and become a mini moon next month.
Instead of a cosmic rock, the newly discovered object appears to be an old rocket from a failed moon-landing mission 54 years ago that’s finally making its way back home, according to NASA’s leading asteroid expert. Observations should help nail its identity.
“I’m pretty jazzed about this,” said Paul Chodas, director of the Center for Near-Earth Object Studies at NASA’s Jet Propulsion Laboratory in Southern California.
“It’s been a hobby of mine to find one of these and draw such a link, and I’ve been doing it for decades now.”
Chodas speculates asteroid 2020 SO, as it is formally known, is actually the Centaur upper rocket stage that successfully propelled NASA’s Surveyor 2 lander to the moon in 1966 before it was discarded.
The lander ended up crashing into the moon after one of its thrusters failed to ignite. The rocket, meanwhile, swept past the moon and into orbit around the sun as intended junk, never to be seen again — until perhaps now.
A telescope in Hawaii last month discovered the mystery object heading our way while doing a search intended to protect our planet from doomsday rocks.
It was promptly added to the International Astronomical Union’s Minor Planet Center’s tally of asteroids and comets found in our solar system.
The object is estimated to be roughly 8 meters based on its brightness. That’s in the ballpark of the old Centaur, which would be less than 10 meters long including its engine nozzle and 3 meters in diameter.
What caught Chodas’ attention is that its near-circular orbit around the sun is quite similar to Earth’s — unusual for an asteroid.
“Flag number one,” he said.
The object is also in the same plane as Earth, not tilted above or below, another red flag. Asteroids usually zip by at odd angles. Lastly, it’s approaching Earth at 12,400 kilometers an hour, slow by asteroid standards.
As the object gets closer, astronomers should be able to better chart its orbit and determine how much it’s pushed around by the radiation and thermal effects of sunlight.
If it’s an old Centaur — essentially a light empty can — it will move differently than a heavy space rock less susceptible to outside forces.
That’s how astronomers normally differentiate between asteroids and space junk like abandoned rocket parts, since both appear merely as moving dots in the sky.
There likely are dozens of fake asteroids out there, but their motions are too imprecise or jumbled to confirm their artificial identity, said Chodas.