"Asteroid" could be an old mission rocket to the Moon
Thought to be an "asteroid" to be trapped by Earth's gravity and turn into a "mini-moon" next month.
But instead of a cosmic rock, the newly discovered object appears to be an old rocket from a failed 54-year-old moon landing mission that is finally making its way home, according to NASA's leading asteroid expert .
I am quite excited about this, Paul Chodas told The Associated Press. It's been my hobby to find one of these and find such a link, and I've been doing it for decades, he continued.
Chodas surmises that asteroid 2020 SO, as it is formally known, is actually the upper stage of the Atlas-Centaur rocket that successfully propelled NASA's Surveyor 2 module to the Moon in 1966 before it was scrapped. The lander ended up crashing into the Moon after one of its thrusters failed to ignite on the way. The rocket, meanwhile, passed the Moon and into orbit around the Sun like garbage, never to be seen again, until perhaps now.
A Hawaiian telescope last month discovered the mysterious object heading our way while conducting a search to protect our planet from dangerous asteroids. The object was quickly added to the list of the International Astronomical Union's Center for Minor Planets of asteroids and comets found in our solar system, which is only 5,000 from the million mark.
The object is estimated to be about 8 meters (26 feet) based on its brightness. That's in the range of the old Centaur, which was less than 10 meters long, including the nozzle, and 3 meters in diameter.
What caught Chodas's attention is that its nearly circular orbit around the Sun is quite similar to Earth's, which is unusual for an asteroid.
Clue number one, said Chodas, who is director of the Center for Near-Earth Object Studies at NASA's Jet Propulsion Laboratory in Southern California.
The object is also in the same orbital plane as Earth, with no tilt above or below, another clue. Asteroids often pass at different angles. Finally, it's approaching Earth at 2,400 km/h (1,500 mph), slow by asteroid standards.
As the object gets closer, astronomers should be able to better map its orbit and determine how much it is pushed by radiation and the thermal effects of sunlight. If it's an old Centaur — essentially a lightweight empty can — it will move differently than a space rock, the weight of which makes it less susceptible to external forces.
This is how astronomers normally differentiate between asteroids and space junk, such as abandoned rocket parts, since both appear simply as moving dots in the sky. There are likely dozens of fake asteroids out there, but their movements are too imprecise or confusing to confirm their artificial identity, Chodas said.
Earth has encountered the object during their respective translations in 1984 and 2002, but it was too faint to be observed from 8 million kilometers (5 million miles) away.
Chodas predicts that the object will spend about four months circling the Earth once it is captured by its gravity in mid-November, and that it will shoot into its own orbit around the Sun next March.
Chodas doubts the object will crash into Earth, "at least not this time."