in advance of transmitting them to the probe. A data storage unit is included to record up to 6,144 bytes of information gathered by the instruments. The digital telemetry unit is used to prepare the collected data in one of the thirteen possible formats before transmitting it back to Earth. Scientific instruments Mission profile Launch and trajectory Pioneer 10 was launched on March 3, 1972, at 01:49:00 UTC (March 2 local time) by the National Aeronautics and Space Administration from Space Launch Complex 36A in Florida, aboard an Atlas-Centaur launch vehicle. The third stage consisted of a solid fuel Star-37E stage (TE-M-364-4) developed specifically for the Pioneer missions. This stage provided about of thrust and spun up the spacecraft. The spacecraft had an initial spin rate of 30 rpm. Twenty minutes following the launch, the vehicle's three booms were extended, which slowed the rotation rate to 4.8 rpm. This rate was maintained throughout the voyage. The launch vehicle accelerated the probe for net interval of 17 minutes, reaching a velocity of . After the high-gain antenna was contacted, several of the instruments were activated for testing while the spacecraft was moving through the Earth's radiation belts. Ninety minutes after launch, the spacecraft reached interplanetary space. Pioneer 10 passed by the Moon in 11 hours and became the fastest human-made object at that time. Two days after launch, the scientific instruments were turned on, beginning with the cosmic ray telescope. After ten days, all of the instruments were active. During the first seven months of the journey, the spacecraft made three course corrections. The on-board instruments underwent checkouts, with the photometers examining Jupiter and the Zodiacal light, and experiment packages being used to measure cosmic rays, magnetic fields and the solar wind. The only anomaly during this interval was the failure of the Canopus sensor, which instead required the spacecraft to maintain its orientation using the two Sun sensors. While passing through interplanetary medium, Pioneer 10 became the first mission to detect interplanetary atoms of helium. It also observed high-energy ions of aluminum and sodium in the solar wind. The spacecraft recorded important heliophysics data in early August 1972 by registering a solar shock wave when it was at a distance of . On July 15, 1972, Pioneer 10 was the first spacecraft to enter the asteroid belt, located between the orbits of Mars and Jupiter. The project planners expected a