As our technology grows, so does the congestion in our space environment. An efficient space traffic management system has become vital to ensuring a sustainable orbital environment for the coming generations.
Since Sputnik in 1957, humankind has witnessed exponential growth in science and technology. As of the past few decades, advancements in satellite and launch technologies have not only paved the way for smaller and lighter satellites, but also allowed large numbers of new satellite operators access to our orbits. From the oldest operating satellite, Vanguard 1, to the more than 2000 Starlink internet satellites, UNOOSA records 8261 satellites in orbit. The growing numbers make sense when we realize our dependence on satellites for communications, internet connection, technological development, navigation, research and so much more.
While we may celebrate the progress the space sector has made in the past few decades, the proliferation of satellites and space debris is a budding concern for the future of the industry. The issue brings us more unease when we understand how increasingly reliant we are becoming on orbital infrastructure for life on Earth. We cannot afford to lose control of our orbital environment or let it become congested to the point of no return.
A viable and possibly optimal solution to manage this challenge would be to establish an efficient space traffic management (STM) system. This would enable moderated access to orbits for space activities in a safe, secure and sustainable manner. STM also prioritizes monitoring the space environment to reduce collision risks of orbital infrastructure so as to ensure the safe operation of satellites in a populated environment. This system will be of great benefit to current and future satellite operators and for the performance of other space missions as well.
Although we may not have a standardized system to implement STM, individual agencies have stepped up to monitor the orbit and prevent collisions. When there is an alert for a possible collision between an active satellite and a piece of space debris, the usual procedure entails the satellite operator making a decision to maneuver their satellite (risking service disruption and propellent cost that can shorten the asset’s lifetime) if the threat of collision is high.
As of recently, these warnings of collision are provided by the US Air Force 18th Space Control Squadron, which tracks space objects in order to predict collision threats. These alerts are sent as Conjunction Data Messages (CDMs) which are delivered to operators around the world for them to make their judgements and do the necessary.
Alerts aside, the effective implementation of STM itself requires a global approach. According to the European Union (EU), a certain level of trust must be built between space faring nations to establish a global STM approach made from regional contributions. Such partnerships and collaborations are necessary in bringing about coordination in the launching and maneuvering of space assets.
Currently, there are no set rules or guidelines to the right of way for satellites. If their operators receive alerts, they stay or give way. But no regulatory framework or prior coordination with other assets are made before launch. This issue can be deduced in the recent event, in September 2019, where the European Space Agency stated it had to move an Earth observation satellite, Aeolus, to avoid a close approach with a Starlink satellite after complaining of a lack of coordination with SpaceX. A later agreement between NASA and SpaceX would grant NASA satellites the right of way when it comes in the event of any close approaches with Starlink satellites.
When close incidences, such as the abovementioned, are becoming increasingly common with congested orbits, it warrants an international framework, global collaboration and bilateral cooperation in STM. The space faring countries and commercial entities should understand and focus on organizing regulatory framework, operational safety and long-term sustainability of the orbital environment for the benefit of the space community.
As the space sector grows, so will its economy. We will be witnessing many more developments and expeditions in the future. But it is imperative that we also understand the ramifications we may have to face if we do not pay heed to the issue of space debris and congested orbits. A system of efficient space traffic management that will mitigate debris removal and collision avoidance is urgent and crucial for safe space activities. We need to cooperate and coordinate as one, global community to ensure a sustainable and secure space environment for the coming generations.