October 4, 1957: The Soviet Union launches Sputnik 1.

Sputnik 1 (“Satellite” or “Companion” 1) was mankind’s first artificial satellite; its successful launch from the Site No. 1 launchpad in Kazakhstan ushered in a new age of rapid technological advancement. If the beginning of the Space Race can be pinpointed to one particular moment, the launch of Sputnik would be the most likely candidate. Although Sputnik itself was only a simple satellite, it set off a number of events in the United States, including the founding of NASA in July of 1958 and the founding of DARPA (Defense Advanced Research Projects Agency); in addition, funding for education (with an emphasis in the sciences and mathematics) increased dramatically.

The actual satellite weighed around 184 lb. It was approximately the size of a beach ball, and it was composed primarily of an alloy of aluminum, titanium, and magnesium. Surprisingly, its launch caused more of a stir in the United States than in the Soviet Union, where newspapers (initially) barely commented or waited until after gauging the world’s reaction to comment. 

Sputnik remained in orbit until January of 1958; that month, the United States launched its own first satellite - Explorer 1.