That portion of a policy's premium that applies to the expired portion of the policy. Although insurance premiums are often paid in advance, insurers typically earn the premium at an even rate throughout the policy term. More Risk Finance and Captives Information from IRMI.
Explorer 1 became the first successfully launched satellite by the United States when it was sent to space on January 31, 1958. A quick response to the Soviet Union's launch of Sputnik 1, Explorer 1's success marked the beginning of the U.S. Space Age.
The Soviet Union beat the US to this, with the October 4, 1957 orbiting of Sputnik 1, and later beat the US to the first human in space, Yuri Gagarin, on April 12, 1961. The race peaked with the July 20, 1969 US landing of the first humans on the Moon with Apollo 11.