Space Systems provide essential support to the operations of defense organizations (e.g., Army, Navy, Air Force), including: intelligence, surveillance and reconnaissance (ISR); launch detection; missile tracking; Earth observation; satellite communications; and positioning, navigation, and timing.
This article provides an overview of counterspace threats and defensive counterspace.
Counterspace Threat Continuum
The counterspace continuum in the above illustration represents the range of threats to space-based services, arranged from reversible to nonreversible effects.
Reversible effects from denial and deception and electronic warfare are nondestructive and temporary, and the system is able to resume normal operations after the incident. Directed energy weapons, cyberspace threats, and orbital threats can cause temporary or permanent effects.
Permanent effects from kinetic energy attacks on space systems, physical attacks against space-related ground infrastructure, and nuclear detonation in space would result in degradation or physical destruction of a space capability.
Space Situational Awareness allows organizations to monitor and track space object activities of adversaries and execute appropriate counter measures.
Defensive Counterspace (DCS)
Space Systems have a range of options available which can reduce their vulnerability to counterspace threats.
Satellites can be designed and deployed with one or more of the following types of countermeasures:
Active and Reactive Defensive Capabilities, including such things as: detection and monitoring of approaching adversary counterspace threats; threat avoidance through autonomous orbit relocation; multi-spectral/electromagnetic/laser/chemical/robotic manipulator countermeasures; and decoy deployment.
System Design to enhance the satellite’s survivability and ability to resist degradation. This includes things such as: nuclear hardening; anti-jam; systems level redundancy; cybersecurity; and stealth capabilities to reduce the probability of detection.
Redundancy is a countermeasure which replaces a few complex, expensive, multi-purpose satellites with many simpler, cheaper, single-purpose satellites.
Reconstitution is a countermeasure which relies upon the ability to quickly replace satellites that have been destroyed. This depends upon having replacement satellites stockpiled: on Earth which would be quickly launched; or maintained in orbit which would be very quickly activated. Alternatively, existing operational satellites could be reprioritized to assume the functions of the destroyed satellites.
Defensive Satellites are satellites designed specifically to: assess adversary satellites capabilities; interfere with adversary satellite operations; or defeat adversary counterspace assets. Defensive satellites would be launched on demand, or maintained on-orbit. The defensive satellites would be tasked with protecting specific satellites. Space Situational Awareness capabilities would be used to identify potential counterspace threats.
The ground segment, which is essential for communications and control, can be made more resilient against counterspace threats by using: diversity in frequency allocation for uplinks and downlinks; diversity in Earth station locations; and in-space alternative communications pathways using laser-based networking.
The satellite’s orbit has advantages and disadvantages in relation to defense against counterspace threats:
LEO satellites are more vulnerable to certain threats. They are close to the Earth selectors, and easy to track and target; they are susceptible to nuclear degradation; they have a distributed ground segment that is harder to defend; and the whole orbit can be rendered unusable for an extended period of time by exo-nuclear detonations.
GEO satellites are harder to target by adversaries due to their high altitude orbit. Compared to LEO, GEO satellites require fewer ground segment facilities. that are easier to defend. GEO satellites have the capacity to host more extensive defensive countermeasures than LEO satellites because of their large physical size and power systems. GEO satellites are also radiation hardened because of their exposure to solar radiation at high altitude orbit and consequently are nuclear-hardened.