On March 4, a piece of man-made missile remnants You will hit the moon.
But it turns out that it is not, as stated in a number of reports previously, Including The New York TimesSpaceX, Elon Musk, who will be responsible for creating a crater on the moon’s surface.
Instead, the cause is likely to be a piece of a rocket launched by the Chinese space agency.
Last month, Bill Gray, developer of Project Pluto, a set of astronomical software used to calculate the orbits of asteroids and comets, announced that the upper stage of the SpaceX Falcon 9 rocket was on a path that intersects with that of the Moon. . The rocket launched DSCOVR for the National Oceanic and Atmospheric Administration on February 11, 2015.
Mr. Gray had been tracking this part of the rocket for years, and in early January, it passed 6,000 miles from the lunar surface, swung by the moon’s gravity around a path that looked like it might crash into a later orbit.
Observations by amateur astronomers as the object slid onto Earth again confirmed the impending impact inside ancient Hertzsprung crater, which is 315 miles wide.
But a Saturday email from John Giorgini, an engineer at NASA’s Jet Propulsion Laboratory in California, changed the story.
Giorgini runs Horizons, an online database that can establish positions and orbits for nearly 1.2 million objects in the solar system, including about 200 spacecraft. A Horizons user asked Giorgini how sure he was that the body was part of the DSCOVR rocket. “It prompted me to look into the case,” said Mr. Giorgini.
He found the orbit to be incompatible with the path taken by DSCOVR, and contacted Mr. Gray.
“My initial thought was, I’m sure I got it right,” Mr. Gray said on Sunday.
But he started digging through old emails to remind himself when this thing was first spotted in March 2015, about a month after DSCOVR launched.
Almost every new object observed in the sky is an asteroid, and that was the assumption for this object as well. It has been granted the designation WE0913A.
However, it turned out that WE0913A was orbiting the Earth, not the Sun, which made it most likely something that came from Earth. Mr Gray said he thought it might be part of the rocket that launched DSCOVR. Other data confirmed that WE0913A passed the moon two days after the launch of DSCOVR, which appeared to confirm identification.
Mr. Gray now realizes that his mistake was to think of launching DSCOVR on a trajectory toward the Moon and using its gravity to swing the spacecraft to its final destination about a million miles from Earth where the spacecraft would provide a warning of incoming solar storms.
But, as Mr. Giorgini pointed out, DSCOVR was actually launched on a direct trajectory not beyond the Moon.
“I really wish I had reviewed that,” Gray said before his January announcement came out. “But yes, as soon as John Giorgini pointed it out, it became clear that I had already erred.”
SpaceX, which did not respond to a request for comment, did not say that WE0913A was not the stage of its rocket. But she probably didn’t track her down either. Most of the time, a Falcon 9’s second stage is pushed back into the atmosphere to burn up. In this case, the missile needed all of its propellant to get DSCOVR to its distant destination.
However, the second stage, unpowered and uncontrolled, was in an orbit that was unlikely to endanger any satellites, and it is possible that people did not track it.
“It would be very nice if the people who are putting these boosters into high orbits would publicly disclose what they put there and where they are going instead of having to do all this detective work,” said Mr. Gray.
But if this wasn’t a DSCOVR missile, what was? Mr. Gray has moved through other launches in the previous months, focusing on those bound for the moon. “There isn’t much in that category,” said Mr. Gray.
The biggest candidate was the Long March 3C rocket that launched the Chinese Chang’e-5 T1 spacecraft on October 23, 2014. That spacecraft swung around the Moon and returned to Earth, where it dropped a small return capsule that landed in Mongolia. It was a test leading up to the Chang’e-5 mission in 2020 that successfully collected moon rocks and dust and returned them for study on Earth.
A computer simulation of WE0913A’s orbit in time showed that it would have flown close to the moon on October 28, five days after the Chinese launch.
Additionally, Mr. Gray said that orbital data from cubes that were associated with the third stage of the Long March rocket “is pretty much a dead ring” to WE0913A. “It’s the kind of case you’re likely to take to a jury and get a conviction.”
More observations this month have changed the prediction of when the object will hit the moon by a few seconds and a few miles to the east. “It’s still like the same thing,” said Christophe Demoutis, an amateur astronomer in northeastern France.
There is still no possibility to miss the moon.
The collapse will occur around 7:26 a.m. ET, but because the impact will be on the far side of the moon, it will be out of view of Earth’s telescopes and satellites.
As for what happened to the Falcon 9 part, “we’re still trying to figure out where the second phase of DSCOVR might be,” Mr. Gray said.
Best guess is that it ended up in orbit around the sun instead of Earth, and it could still be there. This would put her out of view for the time being. There is a precedent for the return of ancient rocket pieces: in 2020, a newly discovered UFO Turns out it was part of a rocket launched in 1966 NASA’s Automated Surveyor Missions to the Moon.
