Space, often regarded as the final frontier, is now a highly contested domain. Over the decades, its significance has grown exponentially, particularly in the context of modern military and civilian applications. Historically, space was viewed as a neutral domain, largely untouched by the conflicts on Earth’s surface. However, as satellites became essential to global communications, navigation, and surveillance, their strategic importance increased correspondingly. Today, military operations heavily rely on satellites for secure communication, GPS-guided weaponry, and real-time battlefield intelligence. Besides establishing space-based systems for military application, major powers have also developed counter-space capabilities, transforming space into a competing ground for military dominance. The once-utopian vision of space as a domain for peaceful exploration has given way to a sobering reality: the militarization of space is no longer a distant possibility but an ongoing process.
Anti-Satellite weapons (ASAT) are difficult to define. In simple words, any weapon that can cause damage to operability of satellite using physical or non-physical means qualify as ASAT. However, many dual use technologies, like Active Debris Removal (ADR) system, designed to clear space debris, can also be used to remove operational satellites. Similarly, ballistic missile defense systems (BMDS) meant to intercept high-speed ballistic missiles at high altitude can also be used to intercept low-orbit satellites.
In brief, any Low-Earth Orbit (LEO) satellite fundamentally faces two types of anti-satellite (ASAT) threats. First: physical destruction of satellite due kinetic impact with any projectile. Such weapons are called kinetic energy ASATs (KE-ASATs) and can be ballistic missile, drone, or other satellite. KE-ASATs can destroy the satellites leaving behind a trail of debris that endangers other assets in orbit. Second: satellites’ functionality can be disrupted, jammed, or even disabled using non-kinetic means like directed energy weapons (DEWs) to “dazzle” or permanently damage satellite sensors, rendering them inoperative; and cyber weapons to disrupt or hijack satellite systems without causing physical destruction.
In 1957, when Soviet Union successfully put the first ever satellite by mankind – called Sputnik-1 – into orbit, United States responded with initiating its anti-satellite ballistic missile projects designated as Bold Orion and High Virgo. Both these missiles used bomber aircraft as launch platform with Bold Orion using B47 Stratojet and High Virgo using B-58 Hustler. United States Navy (USN) also experimented with the idea of ASAT weapon launched from F-4 Phantom fighter aircraft. All these tests, however, failed to deliver requisite results and these projects were eventually cancelled. Soviet Union responded with ASAT program of their own, termed as co-orbitals ASAT, which used on-board conventional warhead to destroy the satellite. Both United States and Soviet Union considered Electromagnetic Pulse (EMP) generated due to high altitude nuclear explosions as potential option for rendering hostile satellites useless. However, due to massive scale of damage, this option was deemed disproportionate and irrational.
On 13 September 1985, United States Air Force (USAF) again demonstrated its ASAT capability by destroying Solwind P78-1 satellite using ASM-135 ASAT missile launched from modified F-15A Eagle fighter aircraft. Despite successful test, the project was not progressed any further. Similarly on 21 February 2008, USN successfully intercepted a damaged and descending USA-193 reconnaissance satellite using RIM-161 Standard Missile 3 launched from a warship. In first decade of 21st Century, China in 2007 and India in 2019 also joined the list of nations which have successfully demonstrated ASAT capability. These tests produced thousands of debris fragments, many of which continue to threaten LEO operations. Recently, in May 2022, Russia allegedly launched a weaponized satellite to target U.S. satellites. This move essentially introduced a new dimension in ASAT operations in which dedicated ASAT-satellite (ASAT-SAT) can be employed to target enemy’s satellites.
One of the most alarming consequences of ASAT tests and other destructive activities in space is the creation of debris. Every piece of debris, no matter how small, travels at extraordinary speeds, capable of inflicting catastrophic damage upon collision with operational satellites The proliferation of debris raises the risk of a “Kessler Syndrome,” a scenario where the volume of debris in orbit becomes so high that collisions trigger a chain of further collisions, threatening all satellites with swarm of uncontrollable space debris. This grim prospect highlights the need for controlling proliferation of ASAT weapons, banning ASAT testing in space and collective collaboration to mitigate threat of debris generation in space. Keeping this in view, in 2022, United States became the first country to outlaw and cease testing of direct-ascent anti-satellite missiles.
Deterrence plays a pivotal role in maintaining stability in space. The logic is straightforward: if a nation demonstrates the capability to retaliate effectively against counter-space attacks, adversaries may think twice before initiating hostilities. This form of deterrence mirrors the principles of nuclear deterrence, where mutual vulnerability discourages first strikes. However, deterrence in space is complex. While the destruction of satellites can have immediate tactical advantages, it also risks triggering broader conflicts or rendering key orbits unusable. Therefore, nations are investing in resilience measures, such as rapid satellite replacement capabilities and decentralized systems.
Traditional satellite systems often relied on a few high-value assets. Modern approaches are shifting toward satellite constellations—networks comprising dozens, hundreds, or even thousands of smaller satellites. These constellations offer several advantages like redundancy, resilience, and affordability. The failure or destruction of one satellite has minimal impact on the overall system. Similarly, constellations are harder to disable entirely, as they require multiple simultaneous attacks. Additionally, smaller satellites are cheaper to produce and launch, making it economically viable to replace them quickly. For instance, SpaceX’s Starlink network consists of thousands of small satellites in LEO, providing global internet coverage. Disabling such a network would require an unprecedented scale of attacks, making it a less attractive target.
As technology is progressing, new defensive strategies and countermeasures are also being developed to safeguard orbiting satellites from ASAT weapons. Satellites can be equipped with on-orbit maneuvering system to dodge potential threats. France, for example, is developing nano-satellite patrollers as well as satellite based lasers to allow orbital evasive maneuver and interception against approaching kinetic threat respectively. Similarly, Rapid Replacement Programs can be undertaken to keep satellite’s active reserves to timely replace the destroyed or damaged satellites. The United States is investing in programs that aim to launch replacement satellites within hours of a disruption. But as the defensive capabilities will mature, the offensive potential of ASAT will also evolve correspondingly, triggering race between offensive and defensive technologies in space.
Despite efforts to mitigate risks, space remains an inherently vulnerable domain. The increasing number of satellites and the expansion of military reliance on space assets ensure that the stakes will only grow higher. In the absence of dedicated internationally recognized arms-control and disarmament body, the unchecked proliferation of dedicated ASAT and dual-use ASAT technologies will continue to pose challenge to strategic stability. The key to overcome this contested environment lies in a combination of resilience, deterrence, and international cooperation.