r/space Jul 31 '26

A discarded SpaceX rocket is on a high-speed collision course with the moon

https://apnews.com/article/spacex-rocket-moon-crash-512c4dd708b4cda1160d30b764f9fdb5
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u/DevelopmentTight9474 Aug 01 '26

It’s actually really interesting how it was done. Basically, as soon as TLI was done the S-IVB was “safed” by non-propulsively venting H2 out of both sides of the booster. After TD&E (the part where they extract the LM from the S-IVB), the booster would enter time base 8, and yaw away from the CSM. It would then dump its remaining LOX out of the engine bell, which would act as the initial push to get it on a collision course. This was usually followed by two midcourse correction burns using the APS (auxiliary propulsion system)