Space Situational Awareness (SSA) is a very specific subfield, but an increasingly important one for safeguarding space operations.
By Rajeswari Pillai Rajagopalan
The third India-U.S. 2+2 strategic dialogue, with the foreign and defense ministers of the two countries, has just concluded. The joint statement issued at the end of the dialogue is a remarkable and significant one. Space cooperation has usually not featured prominently in discussions between the two sides, yet the joint statement noted the agreement among the four ministers to start cooperation on a specific agenda within the broad space domain – Space Situational Awareness (SSA). The importance of SSA cannot be overemphasized given its utility in ensuring safe, secure, and sustainable use of outer space.
As important as space has become, it is also crowded and congested with more than 80 countries active in way or another in this domain. In addition, private companies have plans to launch thousands of satellites for broadband and communication purposes. This will make space traffic management a nightmare in the coming years. The first step is awareness of the space environment. SSA is simply that: awareness about the space environment, which can help ensure safety of space missions by giving collision avoidance information, information about space weather, and related natural phenomenon in space. Unless states are able to develop a clear picture of the space environment that they operate in, space assets could be in danger from both intentional threats and natural hazards. SSA is an effort at collating data on orbiting satellites, old rocket bodies, and other space debris, predicting re-entry of space objects into the atmosphere, and monitoring any threats to spacecrafts and satellites. The overall goal is to generate the ability to monitor, understand, and predict the physical space environment.
There are good reasons for India and the United States to develop a collaborative mechanism to start sharing SSA data. Both are major spacefaring nations with significant investment in space; their societies and militaries are dependent on space for a number of critical functions. Therefore, any disruptions of their space assets would result not only in social and economic disruption but interference in the effectiveness of their militaries as well.
SSA involves collection and analyses of data to convert them into actionable information to deal with threats to space assets. A report by Bhavya Lal et al for the Washington D.C.-based IDA Science & Technology Policy Institute divided the space traffic system into six components. This includes the data collection component “which refers to civil, military and commercial sensors, whether ground- or space-based,” the data processing part, and the data products component, “such as conjunction or collision warnings” so that operators can avoid collisions. Then there’s the oversight and coordination component, which “includes regulations, policies, guidelines, standards, and best practices.” The fifth component is data sharing, which “spans the entire continuum of the space traffic system.” The last component is external factors, “the combination of environmental and operational realities that are driving changes both on the technical and coordination sides.”
This is obviously a complicated set of capabilities that are better handled cooperatively. India has been in the space business for about five decades now but it has developed only limited SSA capabilities. Many other players including China and Japan also do not have extensive capabilities in this regard. As of today, the United States has the largest network – the Space Surveillance Network – which has maintained among the most comprehensive coverage so far, though its coverage of the southern hemisphere is a bit weak. The U.S. is followed by Russia, which has the second largest network and has better coverage of the southern hemisphere. The EU also has a fairly detailed SSA network.
With India’s space program expanding in its scope and sophistication, India’s civil space organization, the Indian Space Research Organization (ISRO) has established a dedicated SSA department at the ISRO headquarters. Prior to this, without a dedicated SSA department, India did not show much interest in collaborating with other countries or their space agencies. But other major space players such as the United States and Japan have been keen to work with India on SSA.
Until now, the ISRO relied on limited data from the North America Aerospace Defense Command (NORAD) for tracking space debris as well as checking on the active and passive satellites in orbit. But this has been insufficient because this did not give India access to full or real-time data because India was not part of the NORAD network. The ISRO could only access the two-line element (TLE) data set, which is a specific format used by NORAD and provided free to the ISRO as well as other space players. TLE provides data on space objects that are orbiting the earth at a particular point in time. But the fact that the ISRO cannot access real-time NORAD data imposes limitations in terms of accuracy and precision of data acquired and delay in tracking objects in space.
The urgency and the need for India to monitor and track space objects and space debris became particularly evident after India’s anti-satellite (ASAT) test in March 2019. This possibly led to the establishment of the ISRO’s Space Situational Awareness and Management Directorate at the ISRO Headquarters, which is an important step as India’s space program grows. India’s decision to establish its own dedicated SSA capabilities also comes from the growth in the number of satellites and counter-space capabilities such as ASATs. India today operates a combination of communication satellites including GSATs and INSATs, navigation satellites (IRNSS constellation), and a series of surveillance satellites such as CARTOSAT and RESOURCESAT series.
As for its SSA capabilities, the ISRO started a new initiative called Project NETRA (Network for Space Object Tracking and Analysis) that will keep track of satellites in Low Earth Orbit to prevent them from being hit by space debris or space weather incidents. The ISRO is also in the process of establishing several observation facilities that would include radars, telescopes, data processing centers, and a control center. These are meant to “spot, track and catalogue objects as small as 10 cm, up to a range of 3,400 km and equal to a space orbit of around 2,000 km.” According to reports quoting ISRO Chairman Dr. Sivan, NETRA will become part of the global efforts at “tracking, warning about and mitigating space debris.” NETRA is to eventually track objects in GEO or geostationary orbit, at 36,000 km.
According to Sivan, India’s SSA capabilities will include a long-range telescope in Leh, a radar in India’s northeast, and a Multi-Object Tracking Radar (MOTR) in Sriharikota, in southern India. As for telescopes, India has a number of optical-infrared observatories including at Bangalore, Pune, Mt. Abu, Nainital, and Hanle. MOTR has been in use already for carrying out space debris proximity analysis in powered and orbital phases during satellite launch, re-entry prediction of debris, and TLE catalogue building. In June this year, the ISRO signed a Memorandum of Understanding (MoU) with Aryabhatta Research Institute of Observational Sciences (ARIES) for collaboration in SSA and Astrophysics. In fact, a telescope that belongs to the ARIES Devasthal Observatory was used for tracking the Indian GSAT-6A satellite.
These are fairly limited SSA capabilities that can be expanded in collaboration with others like the United States, France, and Japan to develop better coverage and more comprehensive SSA systems. India can also take advantage of the amateur astronomer community in building up its capabilities.
Even though late in the day, the ISRO’s steps to establish an SSA Directorate are important. In addition to establishing a certain amount of self-sufficiency in its ability to track and monitor the space environment, it also showcases India as a responsible stakeholder in the space arena. These are baby steps, but SSA is a very challenging problem. As Moriba Jah explains, the absence of standardization and a common “lingua franca” so as to “minimize redundancy and confusion” are issues that need to be addressed. SSA systems themselves will probably need to be adapted with newer applications such as rendezvous and proximity operations, satellite servicing and refueling, inspection, and space-based manufacturing. Another set of challenges will be tracking small satellite constellations that are set to grow exponentially in the coming years. Thus, the SSA challenges will continue to grow manifold.
This also makes international collaboration a necessity. India-U.S. SSA collaboration is a good starting point that can be expanded to include other like-minded partners such as Japan, France, and Australia.
This article originally appeared in The Diplomat.