Attention Fellow NASA Geeks: 40th Anniversary of Apollo 13

The Adler Planetarium, Chicago, IL is hosting some special events in Chicago and online, including Jim Lovell "taking over" the Adler's Facebook fan page and Twitter feed, a panel discussion this evening (tickets available at the link above).

Apollo 13 launched in April 1970, intended to be the second manned landing and exploration of the moon.  Sadly, the public had already lost interest in NASA and the Apollo program, despite the first landing having been only a few months prior in June 1969.
The crew consisted of Commander Jim Lovell - his fourth flight; Command Module Pilot John Swigert, and Lunar Module Pilot Fred Haise, Jr.  Swigert was a last minute replacement after the original CM pilot, Mattingly was exposed to rubella and there was concern he might come down with it during flight.  It was the first space flight for both pilots.
The mission went smoothly until 2 days in when the crew was asked to stir the hydrogen and oxygen tanks.  In space, the contents got "slushy" and separated making estimating quantities a bit tricky, among other problems, so standard procedure was to stir it every so often to mix it up a bit.  Unfortunately, an electrical short ignited the tank insulation, the fire raised pressure in the tank dramatically, and, well, boom.
As a result, the moon landing was cancelled, the crew was left with only minimal power for the main (command) module due to loss of the hydrogen and oxygen needed for power production, and it wasn't even clear if they could successfully return to earth.
The crew in Mission Control worked feverishly trying to puzzle out a new mission plan, figure out how to get the crew home, and figure out how to implement changes in the plan successfully.  One of the first decisions was to shut down everything in the command module to conserve power there for systems that would be vital for re-entry and move the crew into the Lunar Module as a "life-boat" - a very cramped, moist, damp life-boat meant only for 2 people for a limited time that now had to accommodate 3 for an extended period.
There was debate over how best to bring them back - attempt a course change to bring them back directly or continue to the moon on the "free return trajectory" that would require minimal course changes.  The free return took a bit longer, but was in many ways safer - they had no way of knowing how much fuel was left for the maneuvering jets or even if they could successfully fire them with sufficient precision to manage a direct return.

Once that was settled, things calmed a bit until the realization that the carbon dioxide scrubbers in the LM weren't up to the task of maintaining a breathable environment for 3 people for a sufficient amount of time.  In a show of awesome ingenuity, the engineers back on Earth took a look at everything they knew the crew had available on the spacecraft and cobbled together a solution using the scrubbers meant for the command module and managed to explain how to build the crazy thing via audio.  Imagine trying to explain how to build an unfamiliar device to someone when you can't see them and they can't see you - awesome!  That and no fancy calculators or computers and no internet.  Just caffeine, nicotine, and slide-rules, baby.

Deke Slayton shows the carbon dioxide scrubber fix to NASA admins.  For those wondering, yes, duct tape was involved.  Duct tape and enormous nerdy brains.

It worked.

The "mailbox" in place in the LM.  Why, yes, it does appear to be made of WIN and AWESOME.

The remainder of the flight was long, cold, and dark - everything non-essential was powered down, including heat, which caused condensation to build up.  Poor Haise wound up with the urinary tract infection from hell and got to deal with the poor conditions while spiking a fever.  No one could sleep very well being so cramped and uncomfortable and, oh, I don't know, being a wee bit stressed out.
They did though - after some tense moments when radio silence during re-entry lasted a bit longer than estimated, the crew made it through to splashdown.  It's probably one of the finest testaments to human ingenuity in history.

Yeah, cigars are definitely in order here.  Really, I think they could have brought in hookers and blow and no one could have said shit.  

All images courtesy of NASA.