Last act

After their third and final traverse, each J-mission commander drove his rover to a spot roughly 100 metres east of the LM so that the TV camera could look at the sunlit rear of the LM and carry out the one remaining major task left to it – to treat

TV viewers on Earth to the spectacle of the launch of the LM ascent stage and hopefully to follow it as it powered towards the western horizon. As a nod towards the area at the Kennedy Space Center from which invitees and dignitaries would watch Saturn V launches, on his flight Young dubbed the rover’s final position the VIP site.

In the event, the spacecraft’s rapid rise proved difficult to track. When the INCO flight controller commanded a camera move, it took two seconds for the command to reach the pan/tilt head on the rover. It then took a further 1.5 seconds for the move to be seen on Earth if the viewer was watching an unprocessed, uncoloured feed from the Moon. Colour processing added more time. Taking these factors into account as well as the planned time of lift-off and details of the planned trajectory, a command was sent to the camera early enough that it moved in the right way at the right time.

On Apollo 15, Granvil Pennington could make no such attempt. The camera’s tilt mechanism had begun to slip as the temperature rose, and he didn’t dare command any kind of tilt for fear of never being able to return the camera to horizontal. Instead, viewers watched Falcon smartly disappear beyond the top of the picture. The timing wasn’t quite right for Apollo 16, but on Apollo 17 viewers could follow Challenger as Ed Fendell tracked it from lift-off to pitchover and beyond.

For as long as the rovers’ batteries held out, or until a circuit breaker on the Apollo 15 rover popped in the rising temperatures of a high lunar Sun, geologists continued to use the TV camera to view the landing site under the slowly varying illumination of the long lunar day. There was even an unsuccessful attempt to gain coverage of Challengers discarded ascent stage as it was targeted to impact the South Massif.

Around the time that the rovers were being driven across the lunar surface, the press divided the S38 million price tag by the number of rovers delivered and poked fun at how expensive these cars were. A different analysis would point out that these vehicles dramatically raised the efficiency of the surface crews and that, despite the extreme engineering demands place on them, the rovers performed extremely well. Given that the American taxpayer had already invested huge sums in getting to the Moon, the extra expenditure on the LRV more than paid for itself by allowing the system as a whole to give a much greater return on investment.