The Mammoth Book of Space Exploration and Disasters

At the astronauts’ backs, behind the heat shield that protected the bottom of the conical command module during re-entry, was the twenty-five-foot, cylindrical service module. Protruding from the back of the service module was the exhaust bell for the ship’s engine. The service module was inaccessible to the astronauts, in much the same way the trailer of a truck is inaccessible to the driver in the cab. (Since the windows of the command module faced forward, the service module was invisible to the astronauts as well). The interior of the service module cylinder was divided into six separate bays, which contained the entrails of the ship – the fuel cells, hydrogen power relay stations, life-support equipment, engine fuel and the guts of the engine itself. It also contained – side by side, on a shelf in bay number four – two oxygen tanks.

At the other end of the command module-service module stack, connected to the top of the command module by an airtight tunnel, was the LEM. The four-legged twenty-three-foot tall craft had an altogether awkward shape that made it look like nothing so much as a gigantic spider. Indeed, during Apollo 9, the lunar module’s maiden flight, the ship was nicknamed “Spider,” and the command module was called by an equally descriptive “Gumdrop.” For Apollo 13, Lovell had opted for names with a little more dignity, selecting “Odyssey” for his command module and “Aquarius” for his LEM. The press had erroneously reported that Aquarius was chosen as a tribute to Hair – a musical Lovell had not seen and had no intention of seeing. The truth was, he took the name from the Aquarius of Egyptian mythology, the water carrier who brought fertility and knowledge to the Nile valley. Odyssey he chose because he just plain liked the ring of the word, and because the dictionary defined it as “a long voyage marked by many changes of fortune” – though he preferred to leave off the last part. While the crew compartment of Odyssey was a comparatively spacious affair, the lunar module’s crew compartment was an oppressively cramped, seven-foot eight-inch sideways cylinder that featured not the five portholes and panoramic dashboard of the command module but just two triangular windows and a pair of tiny instrument panels. The LEM was designed to support two men, and only two men, for up to two days. And only two days.

Since the Apollo 8 broadcasts all Apollo crews had carried TV cameras, live broadcasts being actually incorporated in their flight plans. By Apollo 13 interest had dwindled and none of the US networks intended to transmit the first broadcast which was made from the LEM. Three days out Mission Control at Houston asked for a “cryostir”, a routine operation which kept the oxygen tanks in good condition. Lovell:

“OK,” Lovell said. “Stand by.”

As Lovell prepared for the thruster adjustments and Haise fnished closing down the LEM and drifted through the tunnel back toward Odyssey, Swigert threw the switch to stir all four cryogenic tanks. Back on the ground, Liebergot and his backroom monitored their screens, waiting for the stabilisation in hydrogen pressure that would follow the stir.

Of all the possible disaster scenarios that astronauts and controllers consider in planning a mission, few are more ghastly – or more capricious, or more sudden, or more total, or more feared – than a surprise hit by a rogue meteor. At speeds encountered in Earth orbit, a cosmic sand grain no more than a tenth of an inch across would strike a spacecraft with an energetic wallop equivalent to a bowling ball travelling at 60 miles per hour. The punch that was landed would be an invisible one, but it could be enough to rip a yawning hole in the spacecraft’s skin, releasing in a single sigh the tiny pressure pocket needed to sustain life.

Outside Earth orbit, where speeds could be faster, the danger was even greater. When Apollo astronauts first began travelling to the moon, one thing they dreaded most but spoke of least was the sudden jolt, the sudden tremor, the sudden boot in the bulkhead that indicated their highest of high-tech projectiles and some meandering low-tech projectile had, in a statistically absurd convergence, found each other like the pairs of fused bullets that once littered the battlefields of Gettysburg and Antietam, and had, like the bullets, done each other some serious damage.