Note from The Cove Team: This is the second part of two-part feature, the first can be found here.

The focus of this article is the Area Denial (AD) of assets in the space domain. To recap the definitions of Anti Access and AD, as defined by The Cove:

• Anti-Access is where the enemy actions inhibit military movement into an area, and
• Area Denial activities that seek to deny freedom of action within an area under the enemy’s control (The Cove, 2021).

The concept of an area under the enemy’s control, in terms of the Space domain, is really focusing on the ability of an enemy to exert influence on an adversary’s satellite in order to deny that adversary the ability to deploy effects within and from the Space domain. The framing of ‘freedom of action’ should be the ability to achieve effects on the ground or deny the enemy the ability to achieve effects on the ground. AD within the Space domain is therefore the ability to prevent effects being deployed in time or in a specific location and therefore deny a satellite’s freedom of action.

Traditional AD threats identified from low-end to high-end peer adversaries rely on a lot of kinetic effects and direct application of weapons systems (Gordon IV & Matsumura, 2013). The ability to carry out AD against satellites can also be achieved through kinetic means. This is certainly a form of AD but also one that has much broader consequences. The creation of debris from a destroyed satellite affects all Space users, including the initiating actor. Such action could – through the creation of that debris field – deny everyone from using that orbital slot, not to mention the risk of increasing the chance of creating a Kessler effect. The Kessler effect, or sometimes known as the Kessler Syndrome, is a point where the debris hits a critical mass creating a cascading collision effect (de Gouyon Matignon, The Kessler Syndrome, 2019). The Kessler effect itself is, in a way, an ultimate form of AD and possibly a new form of 'mutually assured destruction' in Space.

Kinetic effects can be delivered to Space from Earth, as seen by various direct-ascent anti-satellite weapons tests (DA-ASAT) by India, China and the United States. In the Space domain however, the ability to target and track the desired satellite and then launch something that can destroy it is no simple task. This limits the capability to only a few State actors because of the complexity to find, fix, target, and track the appropriate satellite.

The DA-ASAT tests have targeted the Low Earth Orbit (LEO) region, which according to ESA is nominally greater than 160km and less than 1,000km (European Space Agency, 2020). The complexity of building any type of rocket to fly above that to target GPS satellites in a Middle Earth Orbit (MEO) or communication satellites in a Geostationary Orbit (GEO) is another limiting factor that would restrict the amount of actors who could apply this capability.

Inspection satellites have a potential to provide a co-orbital anti-satellite capability. This would in effect provide the ability to reach the MEO and GEO orbits. Beyond reaching much higher orbits, these co-orbital anti-satellites could also be pre-deployed and in orbit well before they would be required to be used in anger. Examples of inspection satellites that could be dual use include Russia’s Kosmos-2524 (Grush, 2020), China’s test satellite Shijian-17 (Weeden & Samson, 2021), and Orbital ATK’s Mission Extension Vehicle (MEV).

The Russian satellite was reported to have released smaller ‘inspection’ satellites. These could, in theory, destroy a mission component of a satellite without creating the same level of debris that a DA-ASAT weapon would, which is perhaps a more ethical choice of weapon. The Chinese and Orbital ATK systems both have the ability to physically interact with another satellite. This could mean either a temporary or permanent disruption to a target satellite without damaging the satellite itself or creating a bigger problem in terms of debris. These have both been demonstrated in the GEO belt; however, there is no reason the capability could not be developed – albeit in a different spacecraft – for the MEO and LEO regions.

Non-Kinetic effects can encompass jammers, high-powered microwave, spoofing, laser dazzling and cyber-attacks (Harrison, Johnson, & Young, 2021). These effects can be applied directly at a satellite from the Earth, from another satellite, or towards the ground infrastructure. The delivery of these capabilities from the Earth means the surface upward, which includes ground and air systems. The versatility of these systems means that it makes sense that they enter service as a mainstay of an adversary’s capability.

Most people understand the concepts of jamming or spoofing a satellite signal. The ability to impact signals from global navigation satellite systems for navigation or jamming communications signals are well appreciated. While affecting the signal from the satellite is one approach, affecting the signal to the satellite is another. Disrupting the command signals that control the satellite and the payload are a viable form of AD that would prevent updated commands from controlling the satellite or payload that would allow them to deliver effects or maintain station keeping.

Lasers, as one capability, have been developed in Australia and overseas. Electro-Optic Systems (EOS) have developed a fixed facility that can target, track and in some instances engage space debris (EOS, n.d.). The ability to use a fixed site laser that can track and ‘move certain types of space debris’ is only a small step removed from putting a hole through a space object. The accuracy of the EOS system, down to 1mm, means that, in theory, they could target specific parts or surfaces of a spacecraft. This could result in specific targeting that could degrade, disable, or destroy a satellite by targeting specific systems on the satellite, including the payload.

High-powered microwave weapons can be used to disrupt a satellite’s electronics, corrupt data, cause processors to restart, or cause permanent damage to electrical circuits and processors (Harrison, Johnson, & Young, 2021). While such a weapon can be used to degrade or destroy a satellite it can be difficult to tell if the weapon was successful or not.

The satellite is a remotely operated system and an adversary’s own ground infrastructure is a critical part of the satellite. To prevent them communicating to their own space assets therefore denies them the ability to control or provide updated commands to their own satellites. Cyber-attacks on ground infrastructure is one of more readily available attacks due to the ability to be targeted by conventional weapons on Earth. A survey of common attack types including social engineering, malware, command and signal injection highlighted that these were even accessible to organised crime, terrorist groups and the motivated individual (Pavur & Martinovic, 2020).

AD may, in the traditional sense, be associated with kinetic effects to deny freedom of movement. The ability to apply non-kinetic effects to enforce AD within the Space domain provides a bountiful capability to deny, degrade and destroy satellites. These non-kinetic effects can be delivered to a satellite from Earth or Space and provide a state with options that may be considered more ethical and proportional than those kinetic effects.