Apollo 13, the third scheduled manned lunar landing, was launched on April 11, 1970, from Kennedy Space Center. The crewmembers were Commander James Lovell, Lunar Module Pilot Fred Haise, and Command Module Pilot Jack Swigert. Swigert had replaced Tom Mattingly just 72 hours before launch when it was discovered that Mattingly had been exposed to German measles and was not immune. As the astronauts were about 80,000 km from the moon, an explosion occurred in the Service Module of Command Module 109, "Odyssey". The electrical power and water in "Odyssey" was lost, so the lunar landing was aborted. "Odyssey" was powered down and the three men moved into the two-man lunar module, "Aquarius". There they conserved food and fuel during the trip around the moon and back to Earth. The Lunar Module descent engine was used to place the spacecraft on a landing trajectory and to speed up the return. Just before re-entry, the astronauts returned to the Command Module and jettisoned the crippled Service Module. Then they jettisoned "Aquarius", which was not designed for atmospheric re-entry, and safely landed in the Pacific Ocean on April 17.