Anti-Satellite Weapons - Overview

SPACE DEFENSE

Achieving space superiority is of primary concern to the Airman as it enables the continuous provision and advantages of space-enabled capabilities to joint warfighting operations. The Air Force describes space superiority as “the ability to maintain freedom of action in, from, and to space, sufficient to sustain mission assurance.” Space superiority may be localized in time and space, or it may be broad and enduring. The physics of space orbital mechanics and treaties on international use of space prevent the Air Force from exerting “dominance” over all or portions of space.

The United States first started work on ASATs over a generation ago. But the threat that these systems were intended to counter, orbiting nuclear weapons, failed to materialize. And these early nuclear-armed ASATs had major operational limitations. The detonation of the ASAT's nuclear warheads would damage American satellites as well as the intended target satellite.

Because of the limitations of early guidance systems, these anti-satellite weapons could only count on placing a warhead within a few miles of their target, which meant that they had to use a nuclear warhead. High altitude nuclear tests in the early 1960s demonstrated that the electromagnetic pulse from an explosion would carry for quite a distance. One test in 1962 set off burglar alarms and darkened street lights across Hawaii, hundreds of miles away, and disabled several American satellites that happened to be in its vicinity.

The sensitive electronics on satellites proved to be particularly vulnerable to nuclear explosions in space. The military utility of such an indiscriminate weapon was not great. As an anti-satellite weapon it threatened to do as much or more damage to friendly satellites as it did to its intended target. When the threat of orbiting nuclear weapons did not materialize, both the American ASATs were dismantled.

During the late 1950's and early 1960's several air-launched ASAT systems were tested by the United States. These grew out of ongoing efforts to develop strategic air-launched ballistic missiles, and did not result in operational systems. But they are indicative of an early and abiding interest in ASAT weapons. Bold Orion, which was tested by the Air Force starting in October 1959, launched rockets from a B-47 bomber. In the two Hi-Ho tests in 1962, the Navy launched rockets from an F-4 fighter. Interestingly, both the Bold Orion and Hi-Ho ASAT test programs of the early 1960s used the Altair as a second stage, the same upper stage as the later Miniature Homing Vehicle ASAT.

The US Army's Nike-Zeus was originally developed as part of an Anti-Ballistic Missile system. After years of research it became clear that it would be largely ineffective as an ABM. According to Paul Stares, "[t]he US Army's proposal to convert the Nike Zeus missile to the ASAT role in November 1957 and later in January 1960 marked the beginning of an almost symbiotic relationship between ABM and ASAT research and development. This was inevitable given the similar requirements and methods to detect, track and intercept both missiles and satellites. Moreover, the possession of exoatmospheric ABM missiles by definition provided a limited ASAT capability or certainly a system that could be transformed into one with relative ease." The first successful US space anti-satellite intercept took place on May 23, 1963, from Kwajalein Island in the Pacific Ocean. Throughout the duration of Project Mudflap or 505, as it was variously known, at least eight of the Nike Zeus ground-launched missiles were fired from that date until January 13, 1966.

The US Air Force, not to be outdone, also tested and deployed several Thor rockets which were modified for the anti-satellite mission. This capability grew out of the Operation Dominic series of high altitude nuclear tests, conducted in 1962. These nuclear-tipped ASATs became operational on Johnston Island in the Pacific in 1964 and could intercept a target at much greater range than the Nike-Zeus. The system consisted of "a thrust-augmented Thor-Delta with three strap-on solid rockets, a combination giving the high acceleration needed to intercept satellites in near earth orbit." The Program 437 Thor system was tested at least 16 times from 1964 to 1970, prior to its retirement in 1976. This system could be restored to operational status on 6 months notice, since the booster components are stored as part of the American capability to resume nuclear testing in the event of the demise of the Limited Test Ban Treaty.

It has been claimed that "Program 437....laid the technological groundwork for the Sentinel, Spartan, Sprint and Safeguard." Both the Nike Zeus and Thor antisatellite systems would have utilized nuclear warheads to destroy their targets. This, coupled with the complexity of their launch procedures, amounted to a limited capability with severe operational constraints. "The respective advantages of the two systems were that the Nike Zeus could react more quickly due to its solid propellant, while the Thor missile could be fired against targets at higher altitudes." Following the retirement of the Thor program, the US emphasis shifted to non-nuclear kinetic kill mechanisms.

The Air-Launched Miniature Vehicle (ALMV) was the primary American ASAT effort in the 1980s. This weapon, launched from an F-15 fighter by a small two stage rocket, carries a heat-seeking Miniature Homing Vehicle (MHV) which would destroy its target by direct impact at high speed. The F-15 can bring ALMV under the ground track of its target, as opposed to a ground-based system, which must wait for a target satellite to overfly its launch site.

An operational force was planned to ultimately number over 100 interceptors. However, by 1986, the program, initially expected to cost $500 million, was estimated at $5.3 to complete. In an attempt to limit costs, the Air Force scaled the MHV program back by 2/3 in 1987. The Reagan Administration canceled the program in 1988 after encountering technical problems with its homing guidance system, as well as testing delays and significant cost growth.

The Army's Kinetic Energy ASAT was the Pentagon's main weapon under research in the 1990s to attack hostile satellites. As with the Air Force's air-launched project, this ground-based interceptor would destroy satellites by homing in and colliding with them. The three-stage missile would extend a sheet of Mylar plastic, known as a "kill enhancement device," which would strike the target and render it inoperative without shattering the satellite. This interceptor would only be able to reach satellites in low earth orbit, up to ranges of several thousand kilometers. The technology was similar to the anti-ballistic missile hit-to-kill interceptor which was first tested successfully in the 1984 Homing Overlay Experiment, and more recently in the Exoatmospheric Reentry Vehicle Interception System tests, conducted under the Strategic Defense Initiative anti-missile program. The Army plans to start flight testing its missile in late 1996 -- the seven flight tests will include two actual interceptions of inactive US satellites in orbit, the other five being close passes to orbiting satellites. Deployment was scheduled to begin in June 1998. According to Defense Department estimates, the KE ASAT could be built and operated for 20 years for $2-2.5 billion.

The Mid Infrared Advanced Chemical Laser (MIRACL) was located at the White Sands testing range in New Mexico. Originally an SDI project, the Pentagon looked at adapting the laser for use against satellites. In addition to MIRACL, the Pentagon was working on two other ground-based ASATs based on excimer and free-electron lasers. Both technologies could be operational in the late-1990s. The directed energy systems would have the ability to destroy large numbers of satellites in a very short period of time, compared to the kinetic energy ASAT.

The outgoing Quayle Final Report to the President on the U.S. Space Program asserted that " ... the nation now more than ever needs a comprehensive space control capability, including ... satellites that are impervious to interference from hostile forces, and a comprehensive antisatellite capability to deny the military use of space to future enemies."

Rejecting this counsel, the Clinton Administration eliminated funding for the Army's ASAT program. However, funding for unacknowledged ASAT programs continues. And there is not indication that any new efforts are being made to make American satellites less vulnerable to potential ASAT threats from other countries.

The Army Space Superiority (SS) Family of Systems (FoS) provides ground based tactically centric space information superiority capabilities to meet current Joint Requirements and validated Training and Doctrine Command (TRADOC) capability gaps. Space information superiority has gained importance with proliferation of satellite technologies and availability of space data products. Adversaries now have near equal access to a full array of space data products which reduces our information superiority. The Army Space Superiority (SS) Family of Systems (FoS) concept consists of ground based sensors for space situational awareness and advanced ground based tactical capabilities to establish and maintain assured space data access and information superiority for support of tactical operations. The Joint Requirements Oversight Council approved the first Initial Capability Document (ICD) for these capabilities in 2007, allowing an initial capability to advance towards Technology Development and Acquisition.

The mission of the Space Superiority Systems Directorate is to develop, deliver, and sustain unrivaled space control capabilities to guarantee space superiority for America. The Space Superiority Systems Directorate at Los Angeles Air Force Base, Calif., equips U.S. forces with space control systems to gain, maintain, and exploit space superiority. As of 2012 had a multi-billion-dollar budget, 350-person program office, and 1,500-person industry team at multiple locations throughout the country to support operational systems worldwide. It directs the planning, development, testing, deployment, and sustainment of a complex and dynamic portfolio of space-superiority capabilities of the highest national priority.

On April 5, 2016 the Boeing Co., Directed Energy and Strategic Systems, Albuquerque, New Mexico, was awarded a $275,000,000 indefinite-delivery/ indefinite-quantity contract for research, engineering, and program management to advance scientific and technical knowledge of ground-based space-superiority capabilities and technology, and then apply and transition that knowledge to achieve Air Force and national goals. Work will be performed at Kirtland Air Force Base, New Mexico; and Maui, Hawaii, and the three task orders are expected to be completed by Nov. 3, 2020. This award is the result of a competitive acquisition with four offers received. Fiscal 2016 research, development, test and evaluation funds in the amount of $987,000; and operation and maintenance funds in the amount of $1,513,000 are being obligated at the time of award. The Air Force Research Laboratory, Kirtland Air Force Base, New Mexico, is the contracting activity (FA9451-13-R-0243).