The Adaptive Optics Revolution: A History

1: Sputnik, Reality, and Technology

1 O N E Sputnik, Reality, and Technology Military research on adaptive optics originated in a smallDepartmentofDefenseresearchanddevelopmentorganizationknown as the Advanced Research Projects Agency or ARPA. That organization pursued cutting-edge research beginning in the 1970s that led to the development of sophisticated adaptive optics technology that supports a variety of military and astronomical systems today. Without ARPA’s financial backing and encouragement, it is unlikely that rapid progress in adaptive optics would have been possible. To understand why ARPA was set up in the first place to support defense research programs, one must return to the 1950s. At that time, volatile political circumstances threatened to disrupt the military balance of power between the United States and the Soviet Union. President Dwight D. Eisenhower’s decision to establish ARPA on 7 February 1958 (by way of DoD Directive 5105.15 and Public Law 85–325, dated 12 February 1958) was a direct response to the Soviet Union’s dramatic launch of the world’s first man-made satellite, Sputnik I, on 4 October 1957. A metallic ball weighing only 184 pounds and measuring about 23 inches in diameter, which circled the earth every 96 minutes at a speed of 18,000 miles per hour in an orbit 550 miles out in space, Sputnik marked the start of the modern space age. It shocked the world and, rightly or wrongly, convinced the U.S. government and the public that the Soviets were far ahead | One 2 PhOTO 1. From the roof of Boston University’s Physical Research Laboratory building, scientists tracked the first Sputnik across the night sky. In back, left to right: Bill Britton, Jim Chadderdon, Grant Ross, Joe Vravel, Bill Attaya, and Ray Babcock; Harold Alpaugh in the foreground. of the Americans in the space race. America’s prestige reached a low point in 1957. Using Sputnik I as their Cold War ace card in the hole, the Soviets took full advantage of every opportunity to remind the world of the superior expertise of the gifted scientists who were responsible for this amazing technical feat.1 The Soviets were not simply engaged in idle talk. Barely 29 days had elapsed since Sputnik I began bleeping across the heavens when the Soviets staked another claim to technological supremacy in space. To add political insult to technological injury, the launch of Sputnik II on 3 November 1957 was even more spectacular, as its payload (1,121 pounds) weighed more than six times that of Sputnik I. Americans winced when they learned that the second Sputnik also carried a live dog, named Laika, suggesting the Soviets already had a program under way to put a man in space.2 Sputnik, Reality, and Technology 3 This was a brutal blow to the Americans in the opening round of an international prizefight that would ultimately decide who would reign in space. The triumphant launch of two consecutive Soviet satellites into orbit—followed by Sputnik III, a 2,914-pound geophysical satellite launched on 15 May 1958—sent a message that the Russians had outpaced the United States in developing the capability to build boosters with enough thrust and lift capacity to place heavy objects into orbit.3 Even prior to the launch of Sputnik I, on 26 August 1957, the Soviet Union had announced it had successfully test-fired the world’s first intercontinental ballistic missile (ICBM), dubbed the R-7. The Soviet Union was ahead of the United States in the missile race. What worried top Pentagon officials was the possibility that the Soviets might launch ICBMs into space loaded with nuclear weapons that could reach targets in the United States. Sputnik had ushered in the space race, but at the same time, in the eyes of American military leaders, it had accelerated a dangerous arms race.4 PhOTO 2. The first U.S. photograph of Sputnik I—the world’s first artificial satellite, which ushered in the Space Age. The dotted line of light represents the satellite’s path. Photo taken by a team of Boston University scientists. | One 4 In reality, the U.S. space program did not lag appreciably far behind the Soviet Union’s. In fact, the American program was ahead of the Soviets in many core areas such as microelectronics, computers, guidance systems, sensors, solid fuels, nuclear warhead design, and survivability of systems. But Soviet development of reliable and powerful launch vehicles—specifically ICBMs—caused the United...