October 4, 1957... the Space Age began.
Erika Lishock and I had the honor, thanks to Roger Launius and others at NASA, of chronicling the steps to that milestone in our book The First Space Race (Texas A&M University, 2004). The late Dr. James Van Allen was kind enough to contribute the Forward, which we believe is the last thing he wrote for publication.
Rather than revisit the technical events, I wanted to comment on a couple of ideas that have arisen since the event: that the U.S. "let" the Soviets launch first, and that the first U.S. program, Project Vanguard, was chosen because it was less military than the competing project (which very likely would have beaten Sputnik to orbit) offered by Wernher von Braun and the Army Ballistic Missile Agency.
The argument that President Eisenhower welcomed or allowed a first Soviet launch is not correct. If it were true, Ike would not have called DoD's (and the nation's) point man on the satellite programs, Donald Quarles, on the carpet and demanded an explanation. Ike's chief of staff wrote that the President was pretty hot about it. Quarles pointed out how the Russians had "unintentionally done us a good turn" related to space law, and Ike saw the logic but was no less incensed that we'd handed the Russians a propaganda coup. No one in the government, then or ever, confirmed any sort of slowdown - only a debatable decision by the Stewart Committee, which opted for the more complex Vanguard, with its promise of better scientific return, over the Army proposal which became Explorer.
(It is true that only a minority of the Committee members had actual
rocket expertise, and most likely accepted the Navy's claim it could do a satellite program nearly as quickly as the Army.)
Nor is it true that a top-level decision had been made to direct the choice to the "more civilian" Vanguard. If it had, Quarles would not have listened to a plea from von Braun and his commander and reconvened the committee for another round of presentations and a second vote.
Sometimes, believe it or not, the Government's official version turns out to be exactly what happened.
author, The First Space Race: Launching the First Earth Satellites
(Texas A&M, 2004)