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Your Chinese Rocket Reentry Questions Answered

The responses to our updates about Long March 5B have been overwhelming. Our Center for Orbital Reentry and Debris Studies expert, Marlon Sorge, answers some of the most-asked questions about the reentry that captured the world’s attention.

ATV-1 Reentry from February, 2015. Image courtesy European Space Agency
The final prediction for the Long March 5B rocket body reentry on May 9, 2:14 UTC.
Long March 5B Reentry Path estimates compared. This image shows that the CORDS’ prediction was the correct path, but estimated the reentry +40 minutes later.
This image shows the reported reentry sites by both SpaceTrack (May 9, 2:14 UTC) and the China Manned Space Engineering Office (CMSEO) (May 9, 2:24 UTC), as well as Aerospace Corporation’s reentry prediction as of May 8, 20:34 UTC. Both reported reentry sites fall on the same revolution predicted by the Aerospace Corporation within 50 minutes of the center of the predicted reentry time window. This is well within the +/- 2 hour reentry window.
This diagram shows the narrowing range of reentry estimates from the start of tracking the Long March 5B.
This plot shows the history of CORDS’ reentry time predictions for the CZ-5B rocket body compared with the actual reentry time reported by SpaceTrack. Each red dot represents the reentry prediction based on a new TLE, a measurement of the CZ-5B’s current orbit . The solid green line represents the actual reported reentry time, and the dashed green lines represent the typical +/- 20% time-until-reentry uncertainty window.

Q: How do we know when and where the rocket body landed?

Space Surveillance Network Map

Q: Why do Aerospace’s orbital predictions differ from the Space Force or other agencies?

Emily Calandrelli via Twitter

Q: Why are updates limited to two to four per day with such a fast-moving object?

@brentpatrick via Twitter

Q: Do weather patterns affect the path of the rocket’s reentry? Is this why it’s difficult to calculate exactly where it will land? What about solar flares?

@JustinCKasper via Twitter

Q: Was the reentry visible from the ground?

Q: Did anyone capture the reentry as it passed over?

@DrChrisCombs via Twitter
CBS News via Twitter
@Magallonico via Twitter

Q: How much debris came down? Is there a debris field?

Q: Can people report sighting a reentry?

Jake Adkins via Twitter

Q: How close did the rocket come to landing in a populated area?

Q: If space debris were to land in your yard, do you get to keep it?

Emily Calandrelli via Twitter

Q: This launch was part of the ongoing assembly of a space station estimated to need 10 more launches to complete. As the pace of launch accelerates globally, will these sorts of debris reentry events become more common?

Sudeep Sarkar via Twitter

Q: Why didn’t we shoot down the rocket body?

Q: What are some of the potential geopolitical ramifications of an uncontrolled reentry?



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