Why ‘bodyguard satellites’ are necessary

SAMPLE return missions to the Moon, a second mission to Mars, the imminent launch of Indians into space and the steady progress towards a permanent space station were, until recently, the tide of optimistic news coverage of the Indian Space Research Organisation (ISRO). However, this positive hum of the news cycle was suddenly interrupted by a ripple of strategic speculation.

An incident reportedly occurred in mid-2024 when a satellite from an unnamed neighbouring country executed a manoeuvre, bringing it within 1 km of a crucial Indian spacecraft in low-Earth orbit. While a collision was avoided, the unusually close approach was perceived as a possible test of capabilities, a silent 'show of strength' in the increasingly contested domain of space.

In 2023, the then ISRO Chairperson, S Somanath, delivering Air Chief Marshal PC Lal's 38th Memorial Lecture titled 'Strategic Capability Development in Space', said that ISRO has "observed spacecraft from friendly nations manoeuvring around Indian space assets, monitoring them."

In the wake of these incidents, reports have emerged citing unnamed sources that India is considering the design, construction and launch of dedicated 'bodyguard satellites'. India is not alone in the emerging concern for the vulnerability of space assets.

The security of satellites, which form the backbone of modern communication, navigation and surveillance, came to the fore with a notable event involving the French-Italian Athena-Fidus satellite, which was approached multiple times by a Russian Luch (Olymp) satellite between late 2017 and early 2018. The French government labelled the Russian satellite's close approach an "act of espionage."

The US' Geostationary Space Situational Awareness Program (GSSAP) satellites conducted a series of close approaches to several non-US satellites between 2016 and 2018, raising concerns about the nature of the manoeuvres.

At the heart of these incidents is a tech capability called Rendezvous and Proximity Operations, or RPOs. RPOs refer to the set of manoeuvres that allow a spacecraft to closely approach and maintain a specific relative position to another space object.

Initially developed for peaceful purposes, such as docking with space stations or servicing aging satellites, RPO tech has advanced in recent decades. With improvements in robotics, autonomous guidance systems and propulsion, these operations have become easier and more precise. A satellite can now be programmed to autonomously navigate towards a target satellite in a different orbital plane, match its velocity and hold a position a few hundred metres away, all with minimal intervention from ground controllers.

The recent Indian SpaDEX technology demonstrator mission of ISRO, which successfully docked two small satellites (SDX01 and SDX02) and later undocked them, involves similar technology.

While this technology holds immense promise for the space sector, enabling in-space servicing and manufacturing, its dual-use nature is stark. The same capabilities that could repair a satellite could also be used to eavesdrop on its communications, inspect it for vulnerabilities, or, in a worst-case scenario, deliberately render it non-operational.

This potential to jeopardise space assets during a conflict, leaving a nation blind and deaf, has triggered a global scramble for defensive solutions.

In the scramble for solutions, the concept of bodyguard satellites has emerged as a viable option. The principle is analogous to its terrestrial counterpart: a dedicated, smaller satellite would be deployed to escort and protect a high-value asset, such as a military, communications or reconnaissance satellite. This bodyguard would be equipped with advanced sensors to continuously monitor the space around its charge, identifying and tracking any object that makes a suspicious approach. The measures could involve physically interposing itself between the threat and the protected satellite, using non-kinetic jamming techniques to disrupt a hostile spacecraft's sensors, or even possessing the capability to disable or destroy an aggressor.

This is no longer theoretical. Japan recently unveiled its defence guidelines, announcing plans to build bodyguard satellites by 2029, citing the development of anti-satellite weapons by other nations.

Following its unsettling experience with the Luch satellite, France commenced the YODA programme, an acronym for 'Eyes in Orbit for an Agile Demonstrator'. It aims to test the very technologies required for a bodyguard satellite. Initially planned for a launch in 2023, then 2024, the demonstrator is now scheduled for 2025.

The EU announced in 2023 a 6.5 million-euro project named 'Bodyguard' under the European Defence Fund. This programme aims to develop an autonomous system capable of tracking threatening satellites and neutralising them.

India's current fleet of operational satellites, numbering around 60, is a vital national resource. It includes 19 communication satellites in geostationary orbit, a large constellation consisting of 30 remote-sensing and Earth-observation satellites in lower orbits, such as the recently launched EOS-09 and NISAR, four NavIC navigation constellation satellites and seven other spacecraft, including AstroSat (astronomy) and SARAL (oceanography, jointly developed with CNES (Centre National d'Etudes Spatiales, French national space agency).

While the concept of dedicated bodyguard satellites remains officially unconfirmed, India's broader strategy for securing its orbital assets is in motion. Anchored by ISRO's Network for Space Object Tracking and Analysis (NETRA) project, this Rs 400-crore initiative is designed to provide crucial Space Situational Awareness (SSA) by tracking objects up to 36,000 km in geostationary orbit.

The urgency of such measures is clear in an increasingly congested space environment. The low earth orbit is becoming crowded with hundreds of nano- and mini-satellites. Concerns are pronounced regarding mega-constellations like Starlink, which prompted ISRO to adjust the orbit of its assets to 574 km. Despite this, more than 80 close approaches of less than 1 km were reported in 2021 alone.

Compounding this is the threat of space junk, with millions of objects travelling in chaotic orbits, any one of which could permanently damage a satellite. NETRA, a network of six radars and 12 optical telescopes distributed across the Indian region, is slated to address the dual challenges of debris and proximity risks. The optical telescope facilities established at the Satellite Photometry, Laser Ranging, and Optical Communication (SPROC) facilities in Ponmudi and Mt Abu, with a third planned for Shillong, can detect objects as small as 40 cm in geostationary orbit, about 36,000 km away, enabling vital Collision Avoidance Manoeuvres. India shares SSA data with global partners and participates in the Inter-Agency Space Debris Coordination Committee (IADC).

The Space-Based Surveillance-III Programme, approved by the Cabinet Committee on Security in October 2023, aims to fast-track the deployment of 52 military satellites for enhanced border surveillance, building on critical lessons from operations like Sindoor, where satellite intelligence proved invaluable. This, too, perhaps will contribute to the safety and protection of India's space assets.

While ISRO has not directly confirmed plans for bodyguard satellites, its 2022 report to the United Nations Office for Outer Space Affairs (UNOOSA), which mentioned the "possibility of establishing 'space-based platforms' for SSA alongside ground-based sensors", is curious and can be construed as a veiled indication that planning for India's own protective sentinels is underway.

TV Venkateswaran is Visiting Professor, IISER Mohali.