Aquarius was the name of the Lunar Module which Jim Lovell and Fred Haise had planned to use during their Moon trip. Instead, the tiny capsule turned into a "life boat" for the Apollo 13 crew.
Fortunately, procedures had been developed - before Apollo 13's emergency - which were implemented to save the men's lives.
This photo depicts Aquarius, after it was disengaged from the command module. It ultimately burned-up during re-entry.
Photo online, courtesy NASA.
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