science

Watchdog also warns retiring Falcon and Dragon could leave US access to orbit short of a backup

NASA's safety watchdog, the Aerospace Safety Advisory Panel (ASAP), had good news and bad news for the space agency, and SpaceX boss Elon Musk quickly disagreed with some of it.

Musk disputed the reported suggestion that approximately 22 launches might be needed to support a landing by the Human Landing System (HLS) variant of Starship on the Moon. "That's way too high," Musk responded on X. "Actual number will be more like 6 to 8."

The US lunar landers being developed for Artemis require refueling in space, meaning additional launches to deliver propellant before astronauts can head to the surface. During Apollo, a single Saturn V launch was enough to send a fully fueled Lunar Module to the Moon.

The problem is demonstrating reliable transfers of cryogenic propellant between spacecraft at the scale these heavier, more complex landers require. Apollo's Lunar Module used hypergolic propellants instead.…