Circling the Moon
In a new autobiography, an Apollo 15 pilot tells what it was like to fly solo.
- By Al Worden With Francis French
- Air & Space magazine, July 2011
Eric Long/ NASM
(Page 2 of 3)
Then it was finally time to undock from Falcon. “It’s away clean, Houston,” I reported as the lunar module separated with a bang. The separation had taken longer than planned, so instead of our scheduled rest break, we jumped back into our chores.
Jim and Dave would have worked until they dropped, they were so dedicated to the mission. “We’re still trying to get cleaned up in here and get suits put away and all that sort of stuff,” I told the ground. “It’s awfully cramped quarters, and there’s an awful lot of stuff to move around.” The spacecraft seemed very different now that three of us were crammed in again. “I kind of liked it here by myself,” I added wistfully.
By the time we finished everything on the checklist, we were exhausted. We slept deeply for nine hours. The next morning, we all felt much better. With the three of us scrambling to accomplish tasks, my day seemed much more complicated. I was happy to have Dave and Jim back alive, but I began to miss working alone, when we didn’t all have overlapping tasks.
I had enjoyed my time in orbit. There was so much to see that I never grew bored. The sunlit part of the moon shifted as the days went by, so there were always new places to view. I could have happily spent a few more days there—the same feeling I get at the end of a great vacation. But it was time to go home.
Two days after Dave and Jim had rejoined me in Endeavour, I fired the main engine to propel us away from the moon. I could feel the steady acceleration as it burned for over two minutes. I warily watched the gauges that told me our engine was burning smoothly, speeding us on the curved pathway out of lunar orbit.
I settled in for our three-day coast back to Earth. Mission control signed off, reminding us that “our ever-watchful eye will be on you while you sleep.”
When I woke the next morning, I had to carry out some critical navigation. We had one shot to get back home, and I wanted to be on course from the beginning. While Houston kept an eye on us to make sure we didn’t stray out of a general path of certainty, I hoped to prove it was possible to navigate to and from the moon without their help. I was aiming for a narrow sliver of horizon on a planet tens of thousands of miles away, and there was no margin for error. This far from Earth, the tiniest changes in direction could result in huge errors once we had traveled the remaining distance in our voyage.
I used my sextant and measured the angle between Earth’s horizon and my preselected stars. However, I also had to choose the right place on the horizon. Our planet is about 8,000 miles across, and the horizon is only 50 miles deep. That sounds tiny, and it looked tiny from so far away, but 50 miles was too deep for what I needed to do. I needed more accuracy.
In my training, I had calibrated my eye for a specific part of the atmosphere. Between Earth’s surface and the blackness of space, the atmosphere looked like narrow bands of colors, mostly subtly different reds, magentas, and blues. On Earth I had experimented in simulations to identify a thin color line I could find consistently. I looked for a particular light blue within the atmosphere, and this reduced the 50-mile depth to a much smaller path as we left the moon. It worked even better than it had in the simulators: We stayed firmly on track.
We were still much closer to the moon than to Earth, but because our planet is so much larger, its gravity pulled on us more. We were now truly falling to Earth. It meant nothing to us in the spacecraft—there was no physical sensation of our incredible speed as we shot through the black void.
It was time for the three of us to float back into our spacesuits and help each other zip up before I went out for my EVA to retrieve film from cameras in the Scientific Instrument Module (SIM) bay. “You have a go for depress,” mission control told us. We slowly began to let the oxygen out of the cabin through a special valve in the hatch. Everything in the airless spacecraft looked the same, but I knew now that if I took off my helmet, I would die.
“We’re getting ready to open the hatch,” Dave reported. “Okay. Unlatch.”
“The hatch is open,” I announced. I poked my head outside and carefully mounted a 16-mm movie camera on the hatch to film my spacewalk. Then, grabbing the nearest handrail, I soundlessly floated outside.
I paused a moment and waited for Jim to poke his head and shoulders out of the hatchway behind me. He would stay there to keep an eye on me while I made my way down the side of the spacecraft. Other than our service module glinting in the sunlight, it looked really black out there. I looked down the length of the SIM bay. “You ready, Jim?” I asked. “I’ll work my way down.”