During that 39-minute spacewalk, Worden retrieved film from the outside of the Apollo 15 service module. In total, the OPS-carried flags spent more than 12 days in space, including almost 67 hours on the moon. During the 18 hours and 35 minutes they were outside on the surface, they ...
The Apollo Service Module's transponder with the lid removed, showing the circuitry inside. The transponder returned the ranging signal to Earth, multiplying the frequency by exactly 240/221. The ranging system The ranging system measured how long a signal takes to travel to the spacecraft and ...