"Houston, we've had a problem" spoken from space

HOUSTON, Texas -- It was April 13, 1970 that the now famous words were spoken from Apollo 13, "Houston, we've had a problem."

Apollo 13 had just experienced an explosion and astronaut Jim Lovell called mission control in Houston to report the problem.

While Lovell's transmission became part of NASA history, it was command module pilot John "Jack" Swigert who actually called Houston first about the problem. Here's the official NASA transcript on the incident.

James Lovell, Mission Commander
John "Jack" Swigert, Command Module Pilot
Fred Haise, Lunar Module Pilot
Jack Lousma, CAPCOM (Mission Control)
NASA Transcript:

Swigert: "Okay, Houston, we've had a problem here."

Lousma: "This is Houston. Say again please."

Lovell: "Houston, we've had a problem. We've had a main B bus undervolt."

Lousma: "Roger. Main B undervolt."

Haise: "Okay. Right now, Houston, the voltage is--is looking good. And we had a pretty large bang associated with the caution and warning there. And as I recall, main B was the one that had an amp spike on it once before."

Lousma: "Roger, Fred."

The Apollo 13 crew and NASA had to overcome a number of serious obstacles to get back home. First, they had to improvise and construct a carbon dioxide filter. Second, they had to operate and return their spacecraft with very little electrical power. The country was captivated by the plight of the astronauts, and on April 18, the crew safely splashed down.