Explorer I was the first American satellite. It was launched four months after the first artificial satellite, Sputnik I, was put into orbit by the Soviet Union, beginning the so-called space race. Although it carried a number of instruments, Explorer I was relatively small, weighing just 30 lbs (13 kg). It stopped transmission of data later in 1958, when its batteries died, but remained in orbit for more than 12 years. Where did it make its fiery reentry? Discuss (http://forum.thefreedictionary.com/postst24220_United-States-Launches--i-Explorer-I--i---1958-.aspx)
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