Space Surveillance and Tracking: a global challenge

31 January 2024
EU SST is the European operational capability that safeguards the space assets of the EU, especially the satellites involved in the EU Space Programme, its Member States and other space operators.
EU SST is the European operational capability that safeguards the space assets of the EU, especially the satellites involved in the EU Space Programme, its Member States and other space operators.

Space is becoming increasingly congested. More than one million space debris objects larger than 1 cm are travelling uncontrolled in Earth’s orbit, putting at risk our space infrastructure and space-based applications critical for our daily lives, such as navigation, communication and Earth observation. It is likely that this risk will increase, as 20,000 new satellites are expected to be launched in the next ten years. To address this challenge, the European Union established in 2014 the EU Space Surveillance and Tracking capability: EU SST.

What is EU SST?

EU SST is part of the EU Space Programme’s Space Situational Awareness (SSA) component. It is the EU’s operational capability that safeguards space-based infrastructure, facilities and services, including spacecraft involved in Galileo, EGNOS, Copernicus and GOVSATCOM, as well as satellites from Member States and other space operators. The EU SST Partnership, composed of 15 EU Member States, has networked its assets to provide, in cooperation with EUSPA as the EU SST Front Desk, three SST services: Collision Avoidance, Re-entry Analysis and Fragmentation Analysis.

Protecting space assets from Europe and beyond

In 2023, EU SST opened its Collision Avoidance service worldwide to all spacecraft operators, as foreseen in the EU Space Regulation. Today, more than 400 satellites are protected by EU SST from the risk of collision with space debris or other spacecraft, and approximately 100 of them are from non-EU operators – such as from the United States, Norway and Switzerland - numbers which are expected to continue growing. The expansion of the EU SST user community significantly contributes to the long-term sustainability of outer space activities: the more space assets are protected, the better our space environment is safeguarded.

The importance of EU SST has proven to be crucial to ensure the safety and sustainability of space activities. In 2023, EU SST detected 15,639 close approaches between space objects, of which 1000 were considered of high risk - requiring in some cases collision avoidance manoeuvres performed by the satellite operators -, and monitored 127 re-entries of space objects into Earth’s atmosphere and 6 in-orbit fragmentations. 

The EU SST Front Desk delivered alerts, based on the information generated by national Operations Centres, to the registered users of the SST services.

The network of sensors from the Member States of EU SST, located across the globe, gathered last year more than 444,000 measurements of space objects per day, thus playing an essential role in the provision of services. These data are shared through a database, and analysed and processed by the Operations Centres to generate the EU SST services.

EUSPA, the EU SST Front Desk

EUSPA is responsible for the EU SST Front Desk operations since 1 July 2023. The Front Desk is the interface for the provision of the EU SST services to currently more than 190 organisations. It operates and maintains the SST Portal, manages service requests, provides support to users, and is responsible for user uptake, performance monitoring and communication activities. 

Looking ahead

In 2024, as the backbone of the EU’s approach to Space Traffic Management (STM), EU SST will work to improve the performance of its current services and develop new ones, enhance its core capabilities and develop new technologies, relying as much as possible on the European SSA commercial ecosystem. EUSPA, in its role as the EU SST Front Desk, will continue supporting a growing community of SST users, enhancing the SST Portal with new features, such as visualisation, coordination and communication tools, and contributing to the security monitoring of the EU SST system.

You can learn more about EU SST here or by reading its leaflet and factsheet.

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Updated: Jan 31, 2024