31 January 1958: Launch of Explorer 1
On January 31, 1958, the United States launched Explorer 1, the nations first artificial satellite, marking Americas entry into the Space Age and its first major achievement in the emerging Space Race with the Soviet Union. The successful launch came just four months after the Soviets had stunned the world with Sputnik 1, and it represented a crucial moment for American prestige during the tense early years of the Cold War.
The pressure to launch an American satellite had become immense following the Soviet successes. Sputnik 1 had orbited Earth in October 1957, followed by Sputnik 2 in November, which carried the dog Laika into space. Americas initial attempt to respond with the Vanguard rocket ended in disaster when it exploded on the launch pad in December 1957, a failure broadcast live on television and dubbed Flopnik by the press. The Armys Redstone Arsenal team, led by the legendary rocket scientist Wernher von Braun, was then given the green light to attempt a launch.
Explorer 1 lifted off at 10:48 PM Eastern Time from Cape Canaveral, Florida, atop a Juno I rocket. The satellite was remarkably small by todays standards, weighing just 30.8 pounds, of which 18 pounds consisted of scientific instruments. In comparison, the Soviet Sputnik 1 had weighed 184 pounds. Despite its modest size, Explorer 1 was designed for significant scientific investigation rather than merely demonstrating technological capability.
The satellite made a discovery that far exceeded expectations. Explorer 1 carried instruments designed by Dr. James Van Allen of the State University of Iowa, which detected belts of intense radiation encircling Earth. These Van Allen radiation belts, as they became known, were the first major scientific discovery of the Space Age. The satellite transmitted data until its batteries were exhausted in May 1958, though it continued to orbit Earth until finally burning up in the atmosphere in March 1970 after completing more than 58,000 orbits.
The success of Explorer 1 electrified the nation and demonstrated that American science and engineering could compete with Soviet achievements. The satellite was a collaborative effort involving Dr. William Pickering and the Jet Propulsion Laboratory, which built and operated the spacecraft; Dr. Van Allen, whose instruments made the groundbreaking discoveries; and Dr. von Brauns team, which provided the rocket. The iconic photograph of these three men triumphantly holding a model of Explorer 1 above their heads became one of the defining images of the early Space Age. Explorer 1s success helped spark the creation of NASA later that year and set America on the path that would eventually lead to the Moon.
