Apollo 13 Mission
In spite of the Apollo 13 accident, some of the scientific investigations planned for the mission were carried out. These included the following:
Atmospheric Electrical Phenomena
As a result of the electrical disturbances experienced during the Apollo 12 launch, several experiments were performed prior to and during the launch of Apollo 13 to study certain aspects of launch-phase electrical phenomena. Measurements taken indicated a significant separation of electrical charge that could possibly increase the hazards of marginal weather launches.
Earth Photography Applied to Geosynchronous Satellites
To aid in a test of the feasibility of performing stereoscopic determination of cloud height at synchronous altitudes, a series of Earth-centered photographs was planned. Eleven photographs were taken, and a precise time record was obtained in order to reconstruct the geometry involved. The experiment was successful and all photographs were of excellent quality.
Seismic Detection of Third-Stage Lunar Impact
With this mission, an opportunity was available to gain further data on large mass impact phenomena on the Moon. Instead of sending the third stage of the launch vehicle into solar orbit, as had been done on previous missions, the trajectory of the Apollo 13 S-IVB was designed to cause it to hit the lunar surface. A target site was selected to allow the seismic signals to be recorded using equipment set up during the Apollo 12 mission.
Pilot Describing Function
This activity, which was originally part of the lunar surface experiments, was considered successful in that data were obtained during manually controlled spacecraft maneuvers on other phases of the mission.
Because of the spacecraft malfunction, there was no landing and no lunar activities were performed. The mission made only a single pass around the Moon and no orbital experiments were performed. Only the activities noted above were completed, primarily because they were performed, or at least initiated, before the oxygen tank explosion.