This is the actual hack that saved the astronauts of the Apollo XIII

This is the mother of all hacks, the genius device that saved the Apollo XIII crew from dying in their emergency return to Earth, as photographed during that trip using one of their Hasselblad cameras. Here are the actual step-by-step instructions that helped turn this mission into NASA's most successful failure ever.

After Mission Control decided to cancel Apollo XIII's moon landing following an explosion of an oxygen tank in the Service Module, the astronauts moved to the Lunar Module in order to save power that was going to be needed later for re-entry.

The only problem with this plan was that the Lunar Module was designed for only two people for a 36-hour period, not three astronauts for 96 hours. They quickly discovered that carbon dioxide was building up fast, putting their lives in extreme danger. They had to change the circular CO2 scrubbers in the Lunar Module for clean ones, but they only had spare square CO2 scrubbers from the Command Module.

In record time, the Crew Systems Division put together an improvised adapter using all sort of weird and random parts, like a flight manual cover, suit parts, and socks. CAPCOM (Capsule Communicator) transmitted the instructions to the astronauts in order to assemble this "mailbox" rigas they called itworking against the clock and trying to surive fight the effects of the poisonous gas which was quickly asphyxiating their brains.

This procedure, which takes approximately one hour to complete, will allow the fitting of a square Odyssey Command Module (CM) scrubber filter through the Aquarius Lunar Module's (LM) round mounted filtration hole and will modify the Environmental Systems scrubber unit. The material is for astronauts to use when CO2 scrubbers fail in the CM, all CM filters are used or in other situations where additional scrubbing of CO2 is required. Crew Systems Division assembled and tested this information.

All required equipment is contained onboard within the Apollo 13 CM and LM.

Cover to the Apollo 13 flight plan (to cover and protect the hose entry)

2 lithium-hydroxide canisters

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This is the actual hack that saved the astronauts of the Apollo XIII