The phrase "Houston, we've had a problem" is a slightly altered version of the actual communication between the Apollo 13 spacecraft and Mission Control in Houston. The full phrase is, "Houston, we've had a problem here." It was spoken by astronaut John "Jack" Swigert on April 13, 1970, while he was aboard the Apollo 13 spacecraft.

The incident occurred during the Apollo 13 mission to the Moon. A few days into the mission, an oxygen tank in the service module of the spacecraft exploded, causing a critical failure. The explosion led to the loss of electrical power and the mission's main objective of landing on the Moon had to be aborted.

The full communication went like this:

Astronaut Jack Swigert: "Okay, Houston, we've had a problem here."
Mission Control (Houston): "This is Houston. Say again, please."
Astronaut Jim Lovell: "Houston, we've had a problem. We've had a Main B Bus undervolt."

This event is famous not only for the phrase itself but for the successful improvisation, teamwork, and problem-solving skills demonstrated by both the astronauts and the ground control team in bringing the Apollo 13 crew safely back to Earth. It was a testament to the training, expertise, and dedication of everyone involved in the Apollo program.