Scientists from the US space agency NASA have said that the near-terrestrial object orbiting the planet observed in the month of September is a Centaur rocket booster from the 1960s.
The object, discovered by astronomers searching for asteroids near Earth using the NASA-funded Pan-STARRS1 survey telescope, garnered interest in the planetary scientific community due to its size and unusual orbit and was studied by observatories around the world, according to a release official.
Further analysis of SO’s orbit in 2020 revealed that the object had come close to Earth a few times in the past few decades, with one approach in 1966 bringing it close enough to suggest it may have originated from Earth.
By comparing the new data with the history of previous NASA missions, Paul Chodas, director of CNEOS, concluded that 2020 SO could be the top-stage Centaur rocket booster of NASA’s ill-fated 1966 Surveyor 2 mission to the moon.
Later, a team led by Vishnu Reddy, an associate professor and planetary scientist at the University of Arizona’s Lunar and Planetary Laboratory, conducted follow-up spectroscopy observations of 2020 SO using NASA’s IRTF at Maunakea, Hawai’i.
“Due to the extreme weakness of this object after the CNEOS prediction, it was a challenging object to characterize,” said Reddy. “We got color observations with the Large Binocular Telescope, or LBT, which suggested that 2020 SO was not an asteroid.”
Through a series of follow-up observations, Mr. Reddy and his team analyzed the composition of the SO 2020 using NASA’s IRTF and compared the spectrum data from the SO 2020 with that of stainless steel 301, the material that Centaur rocket boosters were made of in the sixties.