NASA is skipping next week’s launch attempt of its new moon rocket because of a tropical storm that’s expected to become a major hurricane.

It’s the third delay in the past month for the lunar-orbiting test flight featuring mannequins but no astronauts, a followup to NASA’s Apollo moon-landing program of a half-century ago. Hydrogen fuel leaks and other technical issues caused the previous scrubs.

Currently churning in the Caribbean, tropical storm Ian is expected to become a hurricane by Monday and slam into Florida’s Gulf coast by Thursday. The entire state, however, is in the cone showing the probable path of the