Mysterious object in solar orbit identified as upper stage for Surveyor 2
Since August astronomers have been trying to figure out the nature of a mysterious object in solar orbit that did not match their expectations for either a comet or an asteroid. Dubbed 2020 SO, astronomers have now identified it as the upper stage booster used to send the unmanned lunar lander Surveyor 2 towards the Moon in 1966.
Surveyor 2 was a failure when it began tumbling and crashed into the Moon instead of doing a soft landing. Its upper stage meanwhile was sent on a path that would have it miss the Moon and go into orbit around the Sun. That orbit finally brought it back to Earth this year.
2020 SO was captured by Earth’s gravity in November and came within 27,400 miles from Earth on December 1. That’s when Reddy and his colleagues at the IRTF were able to capture the infrared spectrum of another Centaur D rocket booster—this time from a 1971 launch of a communication satellite. When they compared that spectrum to the data gathered about 2020 SO, the spectra matched. 2020 SO is also a Centaur rocket booster, most likely the one used for the Surveyor 2 mission.
2020 SO is now moving away from the Earth and should escape Earth’s gravity within a few months, at which point it will follow a new solar orbit. But astronomers expect it to return to Earth in 2036, and they will be ready to learn even more when it does.
This booster is essentially an early example of space archeology. Someday colonists in space will go and catch it to bring it back to one of their museums on the Moon or Mars, to be studied and admired as a major marker of their own past history.
Since August astronomers have been trying to figure out the nature of a mysterious object in solar orbit that did not match their expectations for either a comet or an asteroid. Dubbed 2020 SO, astronomers have now identified it as the upper stage booster used to send the unmanned lunar lander Surveyor 2 towards the Moon in 1966.
Surveyor 2 was a failure when it began tumbling and crashed into the Moon instead of doing a soft landing. Its upper stage meanwhile was sent on a path that would have it miss the Moon and go into orbit around the Sun. That orbit finally brought it back to Earth this year.
2020 SO was captured by Earth’s gravity in November and came within 27,400 miles from Earth on December 1. That’s when Reddy and his colleagues at the IRTF were able to capture the infrared spectrum of another Centaur D rocket booster—this time from a 1971 launch of a communication satellite. When they compared that spectrum to the data gathered about 2020 SO, the spectra matched. 2020 SO is also a Centaur rocket booster, most likely the one used for the Surveyor 2 mission.
2020 SO is now moving away from the Earth and should escape Earth’s gravity within a few months, at which point it will follow a new solar orbit. But astronomers expect it to return to Earth in 2036, and they will be ready to learn even more when it does.
This booster is essentially an early example of space archeology. Someday colonists in space will go and catch it to bring it back to one of their museums on the Moon or Mars, to be studied and admired as a major marker of their own past history.