spacewatching:

Apollo 13, NASA’s third crewed mission to the moon, launched on April
11, 1970. Two days later, on April 13, while the mission was en route
to the moon, a fault in the electrical system
of one of the Service Module’s oxygen tanks produced an explosion that
caused both oxygen tanks to fail and also led to a loss of electrical
power. The Command Module remained functional on its own batteries and
oxygen tank, but these were usable only during the last hours of the
mission. The crew shut down the Command Module and used the Lunar Module
as a “lifeboat” during the return trip to Earth. Despite great hardship
caused by limited power, loss of cabin heat, and a shortage of potable
water, the crew returned to Earth, and the mission was termed a
“successful failure.”

This photograph of the Mission Operations Control Room in the Mission
Control Center at the Manned Spacecraft Center (now Johnson Space
Center), Houston, was taken on April 13, 1970, during the fourth
television transmission from the Apollo 13 mission. Eugene F. Kranz
(foreground, back to camera), one of four Apollo 13 flight directors,
views the large screen at front as astronaut Fred W. Haise Jr., Lunar
Module pilot, is seen on the screen.

[What could possibly go worng? – ed ]