Pioneer 4 was an American spin-stabilized unmanned spacecraft launched as part of the Pioneer program on a lunar flyby trajectory and into a heliocentric orbit making it the first probe of the United States to escape from the Earth's gravity. It was launched on March 3, 1959 and passed the Moon at a distance of 60,000 km (37,300 mi). Following this attempt, Pioneer 1 and Pioneer 2 were turned over to United States' newly formed National Aeronautics and Space Administration (NASA). It carried a payload similar to Pioneer 3: a lunar radiation environment experiment using a Geiger-Müller tube detector and a lunar photography experiment. Pioneer 10 (originally designated Pioneer F) is an American space probe, launched in 1972 and weighing 258 kilograms (569 pounds), that completed the first mission to the planet Jupiter. Launched on March 3, 1959, NASA's Pioneer 4 was the first American mission to escape Earth orbit and the second of two early attempts by the United States to send a spacecraft to the Moon. The spacecraft achieved its primary objective — to put itself on a trajectory from Earth to the Moon. It was a spin-stabilized vehicle. Pioneer 4 was an American spin-stabilized unmanned spacecraft launched as part of the Pioneer program on a lunar flyby trajectory and into a heliocentric orbit making it the first probe of the United States to escape from the Earth's gravity. The first vehicle, Pioneer 0, was launched by the USAF and was destroyed 77 seconds after launch when the rocket's first stage exploded. Pioneer 4 was the first U.S. spacecraft to escape the Earth. Fifty years ago, Pioneer 4 became the first U.S. satellite to escape the earth’s gravity as it rocketed toward a close encounter with the moon. Pioneer 4 was a spin-stabilized unmanned spacecraft launched as part of the Pioneer program on a lunar flyby trajectory and into a heliocentric orbit making it the first U.S. probe to escape from the Earth's gravity.
Only the diminutive 6.1 kilogram (13.4 pound) Army-JPL Pioneer 4 launched on March 3, 1959, by a team led by famed German rocket engineer Wernher von Braun managed to escape the Earth and make it anywhere near the Moon. Pioneer 1 was the first spacecraft launched by NASA. This unmanned spacecraft launched from Cape Canaveral in 1959 to photograph the moon during a close flyby. It was tracked to 655,000 km before its batteries were depleted at about 84 hours. Pioneer 3 was the same kind of craft.