As the crew watches the Moon pass beneath them, Lovell laments his lost dream of walking on its surface, then turns his crew's attention to the business of getting home. With Aquarius running on minimal electrical power and rationed water supply, the crew suffers from freezing conditions, and Haise develops a urinary tract infection. Swigert suspects Mission Control is concealing the fact they are doomed; Haise angrily blames Swigert's inexperience for the accident; but Lovell squelches the argument. As Aquariuss carbon dioxide filters run out, concentration of the gas approaches a dangerous level. Ground control improvises a "Rube Goldberg" device to make the Command Module's incompatible filter cartridges work in the Lunar Module. With Aquariuss navigation systems shut down, the crew makes a vital course correction manually by steering the Lunar Module and controlling its engine.
