The Ill-Fated Space Odyssey of Apollo 13.
copyright Time Inc. 1970
SC--Okay, we'll do it. And we want to make sure we can talk back and forth now to make sure we get this burn off right.
Getting it off right would take not only accurate timing but accurate positioning of the spacecraft.
CAPCOM--And now we want to ask you a question about alignments, and so forth. We wanted to know if you can see any stars out of the AOT (Alignment Optical Telescope).
SC--In this attitude that we're pitching around I cannot use the AOT to see stars. The Command Module is just radiating too much light into the telescope.
CAPCOM--How about using the Service Module to cast a shadow on the Commander' s window. If you do that, can you see stars?
SC--We tried to do it. The light shines off our quads, which makes it difficult to see stars. We do have the Earth and Moon, if that can be of assistance. Another problem: Right now I'm looking out the right window and it's pretty dark out there, but there are about a thousand or so foam stars out there--left over from the debris. It's hard to discern what's real and what's not.
Ultimately, Mission Control would come up with a computer solution for lining up the spacecraft by sighting on the Earth, Sun, and Moon through the telescope.
The mission clock now showed 61:28:43, which was 3:42 a.m. EST Tuesday and it was time for the critical burn which would take the spacecraft out of the hybrid trajectory and place it in free return. The engine to be used for this burn was that of the Descent Propulsion System (t)PS) of Aquarius. The conversation went like this:
CAPCOM--Aquarius, you're go for the burn.
SC--Master arm's on. One minute.
CAPCOM--Aquarius, you're looking good.
SC--All shut down.
And a little later:
CAPCOM--Aquarius, check your master arm off, please.
SC--Okay, Houston, burn' s complete. Now we have to talk about powering down.
The first milestone on the journey home had been passed.
Even without another burn, the spacecraft would return to Earth for a landing in the Indian Ocean. Emergency preparations for the pickup would have to be completed, but that could be done. And there still remained in the flight plan the second critical burn to obtain a quicker trip and landing in the Pacific.
Haise stood watch, while his fellow astronauts tried for some fitful sleep in the chilly Command Module--chilly and dark because its power supply was cut off.