Usage of space by own forces and its denial to adversary has grown to become essential for modern militaries. Today, space is increasingly being viewed as enabler for conduct of own operations and the ‘Achilles heel’ which if targeted can cripple adversary’s war waging efforts. In order to preserve their rights to use space, militaries of the world need to be watchful of events inspace. Situational awareness of space is thus an increasingly felt necessity for operations in space and on ground.

By Pushpinder Bath

Space Situational Awareness (SSA) is the knowledge/observation of activities, objects/particles and energies in space. These activities, objects/ particles and energies in space can be natural or a part of human endeavours.

Global Capabilities in SSA

Development of indigenous SSA capabilities entails creation of an elaborate space surveillance network comprising satellites, radars, telescopes and ground stations. Presently very few countries have ventured in this domain as it is a very cost prohibitive project. US is the world leader in SSA, hence their capabilities can be taken as a benchmark for assessment of capabilities of other countries. Therefore, current standings of China and India in the domain of SSA should be viewed in reference to USA.


US spends a huge amount on SSA, which is largely financed by the Department of Defence. US operateshundreds ofgeographically dispersed sensors owned by military, civil or intelligence community. Various segments of US Space Surveillance Network (SSN) have been discussed below:-

Space Segment

Space segment of SSN includes deployment of sensors in space for generating SSA. Current US projects providing SSA from space are asunder:-

i. Space Based Space Surveillance (SBSS)5

This project includes theUS Satellite ‘Block-10 Pathfinder’launched in 2010 to observe orbiting space objectsin Low Earth Orbit (LEO), Medium Earth Orbit (MEO) as well as Geostationary Earth Orbit (GEO). The satellite can observe objects of the size of one meter cube up to the altitude of 36,000 Km from Earth.

ii. Geosynchronous Space Situational Awareness Programme (GSSAP) 6

Placed in GEO and operated by US Air Force (USAF), the GSSAP satellites GSSAP 1 and 2 were launched in 2014 and GSSAP 3 and 4 were launched in 2016. These satellites provide surveillance cover to other US critical constellations like Space Based Infra Red System (SBIRS) employed for missile defence and the Advanced Extremely High Frequency (AEHF) constellation, which provides jam-proof communications for the US President even during a nuclear event.

European Space Agency (ESA)

Bitter experiences with US over sharing of SSA information, formed the basis of the ESA’s forays in the SSA domain, commencing from January 2009. ESA satellites Proba-2 and 3, SOHO, Gain and Swarm are tasked with SSA. It has at least a dozen ground facilities located in Europe and South America. The SSA activities undertaken by ESA are as under:-

a. SSA data collection and coordination.
b. Development of applications and user interfaces for sharing.
c. Asteroid attack mitigation techniques.
d. Testing and validation of radar detection technologies.
e. Research in satellite laser ranging.
f. Development of optical surveillance technologies.


Russia has its own space surveillance network. Russian radars are spread over the complete landmass of the erstwhile USSR. However, with bilateral agreements, Russia continues to operate them even today. Russian sensors are primarily ground based and augmented by ship based sensors. Ship based sensors provide them flexibility and redundancy. Apart from the Russian mainland, their SSA sensors are deployed in Azerbaijan, Belarus, Kazakhstan and Tajikistan. There are also a few trans-continental telescopes deployed in Asia, Africa and South America.


China has a network of phased array radars for tracking objects in LEO till 3000 Km of altitude at Jiangxi, Hainan, Xuanhua, Changchun, Henan, Kunming and Kashi. China also operates Yuanwang tracking ships for increasing its surveillance coverage10. In addition, it has four telescopes at the Purple Mountain Observatory in Nanjing. In 2013, China commissioned a tracking station at Ngari, in the Tibetan Autonomous Region (TAR), which is can enable China to track all Indian satellites11. A similar facility has also been commissioned by China in Patagonia, Argentina, which is believed to be utilised for tracking US military satellites. Nicknamed as ‘Heavenly Eye’ or ‘Tinyan,’ China has also built the world’s largest radio telescope here with an aperture of 500 m.


Japan is at a nascent stage of developing its space surveillance network. It has commenced installing radars for scanning space objects in the range of 200 to 1000 Km from Earth. However, optical telescopes are being designed to observe up to 36,000 Km. With the development of its SSA capabilities, Japan would be able to detect space objects of the size of up to 10 cm in a near timeframe.


India is due to undertake Aditya-L1 mission towards the end of 2020, aboard PSLV XL with the aim of observing solar corona activities. Hence, it will assist in predicting hazardous space weather. This project marks the beginning of India’s forays in space in the direction of SSA, albeit in a limited manner. India’s ground segment of SSA is also at a nascent stage. ISRO has commissioned a Multi-Object Tracking Radar (MOTR)12 with a capability of tracking objects of the size of 30×30 cm at an altitude of 800 Km and 50×50 cm up to 1000 Km. The radar located at Sriharikota can track up to 10 objects simultaneously. The radar may have dual usage in the field of air defence for tracking ballistic missiles. In addition, DRDO’s has developed the ‘Super Swordfish’ radar13 capable of detecting objects in space at an altitude of 1500 Km. In 2018, ISRO commissioned the SSA control centre at Bengaluru to plan and coordinate all research and development in the domain of space. India also has a few space observatories spread across Indian landmass. These are as under: –

a. Indian Astronomical Observatory consisting of a 2.01 meter optical-infrared Himalayan Chandra Telescope (HCT) and a High Altitude Gamma Ray (HAGAR) Telescope at Hanle near Leh.
b. Devstahal optical telescope built in collaboration with Belgium, is situated at Nainital and was dedicated to the nation by Prime Minister Narendra Modi in March 2016.
c. Gauribidanur radio observatory is a radar-based observatory located in Karnataka.
d. Giant meter wave radio telescope observatory is located in Pune and it is the largest interferometry observatory in the country. It consists of about three dozen radio telescopes of diameter 45m each thus providing a base diameter of 25 Km.

India has taken some initiatives in international cooperation to develop SSA capabilities. The US-India Joint Statement of September 2014 identified collaboration in SSA and collision avoidance as one of the potential areas of cooperation. By February 2016, a bilateral arrangement for sharing of information had been setup between US and India for tracking movement of satellites and collision avoidance. During his visit in 2018, French President Emanuel Macron signed a SSA cooperation agreement with India. Recently in March 2019, India-Japan space dialogue resulted in an understanding between the two countries on need to share SSA information.

Way Ahead for India

The idea of utilising space for national security has recently begun to gather foothold. In the future scenario of net-centric operations, Indian military is likely to be using space-based services for satellite communications, surveillance, and navigation and targeting. The Indian Navy is reliant on GSAT-7 for its maritime communications and the Indian Air Force uses GSAT-7A. Apart from these communication satellites, the defence forces are utilising the data from nearly a dozen surveillance satellites and the IRNSS constellation. The number of defence satellites is likely to grow manifold in the years ahead. The newly raised Defence Space Agency (DSA) is expected to control the Defence Image Processing and Analysis Centre (DIPAC) and the Defence Satellite Control Centre (DSCC). It will not only be responsible for all military space projects but will also oversee the development of counter space capabilities. The conduct of ASAT test by India in 2019 shows India’s new resolve in the space domain. To put it across in brief, Indian military’s reliance on space assets is all set to increase in future. Further, with this increased reliance will also grow the need to secure our critical defence space assets. If the military were to base their operations on space assets, development of SSA capabilities needs to be seriously considered. It is also important to consider the emergence of China as a space power in our neighbourhood. Not only did China successfully conduct a direct ascent ASAT test in 2007, it has also been surreptitiously engaged in the development of Directed Energy Weapons (DEWs). China’s declared strategy of informationised warfare and consequent increase in space activities needs to be monitored. The point to ponder is that monitoring China’s activities in space is exclusively a military/ security necessity and will not invoke concrete actions till such time the Department of Space and ISRO continue to view SSA purely from the civil perspective.

Majority of space faring nations today rely on USA for provision of SSA data. This allows US to selectively part with the data that it wishes to divulge. On 03 February 2015, the US meteorological satellite DMSP-F13 exploded in near vicinity of European Eumetsat satellite. No prior information of a possible explosion was conveyed by US to ESA, citing that it was accidental due to battery over heating. However, ESA felt that telemetry information of a spike in battery temperature would have already been available with USA. It can thus be understood that data flow on SSA from USA is not perennial even to its closest allies. In the field of navigation, it was the foreign control over GPS that led India to conceive its own indigenous satellite navigation post the Kargil war. Similarly, we need to seriously consider the need to develop our indigenous SSA capabilities to safeguard our space assets. However, the space surveillance network required for acquiring indigenous SSA capabilities entails heavy financial implications. Therefore, we need to adopt a cost effective approach towards its implementation. A national level task force headed by the National Security Advisor (NSA) needs to be created having representatives from the Department of Space, Ministry of Defence, Ministry of Finance, National Technical Research Organisation (NTRO), Defence Space Agency (DSA) and the Service Headquarters. The task force so created should be able to chalk out a roadmap for development of India’s SSA capabilities. It would be ideal to nominate DSA as the executive agency towards the implementation of the project for creation of a space surveillance network. A collaborative concept could be considered with data being provided by radars and telescopes owned by ISRO, defence services and private companies. Data received from international cooperation and open source could also be be factored to generate a fused space situational picture.


India is amongst the major space faring nations in the world. Ever since its inception, the focus of Indian space programme has been on societal applications and economic development. This was also in line with the Outer Space Treaty, which considers space as an arena of global commons. However, unlike India, some nations have kept their national security needs as their primary reason for venturing into space. Such nations have taken a clear lead in niche domains such as SSA and are on a spree to control space and deny its use to other nations. As space plays an increasing role in the domain of national security, SSA has emerged as the stepping stone towards ensuring continuity of own access to space. Concept of informationised wars demands continued availability of space assets and thus necessitates their security. To secure space assets it is essential for military planners to know what’s in space. SSA therefore is the key to space based operations. While the US has a clear lead in the field, EU, Russia and China have also made appreciable progress. We are as yet at a very nascent stage in this domain with very limited assets. Under the given circumstances, India needs to adopt a considered policy that integrates both societal and national security needs in a balanced manner.

This article first appeared in and it belongs to them. The author is a research associate with VIF.