Upon looking at the data, Paul Chodas noticed something strange about the near-earth object designated as the 2020 SO.
It was probably one of tens of thousands of cosmic rocks that astronomers discovered blowing wind through our neighbors in space. Although these solar system debris is mostly harmless, scientists identify and track everything possible in case an object appears to be in the path of collision with Earth. Chodas is the head of NASA’s Center for Near-Earth Object Research at the Jet Propulsion Laboratory in California, who evaluates observations of these objects on a daily basis.
And to Chodas, 2020 SO It didn’t look like an asteroid. Instead, it seemed to be much more rare. It was once an abandoned rocket body that carried a spacecraft to the moon.
In an interview with Space.com at the end of September, Chodas told Space.com, “I think this is such a rocket stage, even on the night it was announced.
Now, ongoing observations over almost a month have confirmed that the 2020 SO is behaving more like a spent rocket stage than just space rocks hitting sunlight.
“Our recent orbital calculations for this object clearly show that it is being influenced by force rather than gravity, perhaps solar radiation pressure,” he said in an email update, saying that the object is not a cosmic rock. Strong evidence.” .
“within asteroid Chodas isn’t easily pushed back in an interview with Space.com in the original interview. “But like a rocket stage, empty cans will be pushed out,” he said.
However, he did not need constant observation to suspect that previous cosmic rocks were actually human fragments. In 1966, the NASA mission was sent to: Surveyor 2 On the moon.
Chodas is one of those scientists who have been keeping an eye on such objects for over 10 years. “We are [or] He said: “I’ve been looking into asteroid orbits for several years to see if there is an asteroid orbit in orbit around the sun that may have been associated with the launch.”
And 2020 SO is the best match so far. Two features that stand out especially in the object’s journey are its slow speed and how closely the trajectory around the Sun matches the Earth’s own orbit. Asteroids don’t tend to behave that way. The Earth itself travels much faster regardless of its path around the Sun.
Instead, Chodas calls out that the orbit of the 2020 SO is the rocket body in the mission. month. “It was definitely not because it would be in orbit from launch to Mars or Venus or another planet,” Chodas said. “It has all the features of the lunar mission,” he said of the object’s orbit.
In particular, the 2020 SO looks like an object trying to land a spacecraft on the moon. Smooth, so not particularly fast. “We had to slow down the ship. We want to approach the moon fairly slowly,” Chodas said. “So the rocket body missed the moon and barely orbited around the sun.” (In the meantime, the Surveyor 2 spacecraft itself has ruined the soft landing Going down to the moon surface.)
That’s the cause of the slow near-Earth orbit that popped out of the Chodas. “That’s why I initially doubted that this could be a rocket body, and on a lunar probe,” he said.
Chodas was able to rewind its orbit to determine when SO left the Earth-Moon system in 2020. answer? Late 1966. But the 60s, of course, tied to the moon Space raceAnd 10 missions between the US and the USSR were launched on the moon that year.
But between the later launch date, the details of the trajectory needed to land on the moon smoothly rather than simply orbiting, and the relative size of the potential rocket body, Chodas said that the upcoming 2020 SO will actually Centaur high level It was used to launch NASA’s Surveyor 2 mission on September 20, 1966.
The identity has not been verified, he said in the update email. Although it seems “more and more likely,” he wrote. He and his colleagues are still analyzing the forces that would have acted on an object over the past half century.
But the initial data, he said, are convincing evidence of the situation.
In an original interview, Chodas said, “This orbit is known very accurately, so you can be sure of the energy and direction and geometry the rocket left the moon in 1966.” “Speed, proximity to the moon, date, everything is suitable for Surveyor 2 missions. Everything matches that shot and not the other shots.”
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