- explorer
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/ik splawr"euhr, -splohr"-/, n.1. a person or thing that explores.2. a person who investigates unknown regions: the great explorers of the Renaissance.3. any instrument used in exploring or sounding a wound, a cavity in a tooth, or the like.4. (cap.) Also called Explorer Scout. a person between the ages 14 and 20 who is an active participant in the exploring program sponsored by the Boy Scouts of America.5. (cap.) Aerospace. one of a long series of U.S. scientific satellites: Explorer 1 (1958) was the first U.S. artificial satellite.[1675-85; EXPLORE + -ER1]
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Any of the largest (55-member) series of unmanned U.S. spacecraft, launched between 1958 and 1975.Explorer 1, the first satellite sent into orbit by the U.S., discovered the innermost Van Allen radiation belt. Other notable craft in this series include Explorer 38 (1968), which measured galactic radio sources and studied low radio frequencies in space, and Explorer 53 (SAS 3; 1975), which investigated X-ray and gamma-ray sources within and beyond the Milky Way Galaxy.* * *
▪ satellitesany of the largest series of unmanned U.S. spacecraft, consisting of 55 scientific satellites launched between 1958 and 1975. Explorer 1 (launched Jan. 31, 1958), the first space satellite orbited by the United States, discovered the innermost of the Van Allen radiation belts (Van Allen radiation belt), two zones of charged particles that surround the Earth. Other notable craft in the series include Explorer 38 (July 4, 1968), which measured galactic radio sources and studied low frequencies in space, and Explorer 53 (May 7, 1975), which was sent out to explore X-ray sources both inside and outside the Milky Way galaxy.* * *
Universalium. 2010.