Why is this relevant?

Space-based services applications such as communication, navigation, and Earth observation have become an integral part of everyday life. This is also reflected in the increase of satellites in space: more than 50 000 satellites are expected to be launched in the next decade.
In addition, more than 1 million pieces of space debris larger than 1 cm are orbiting the Earth, and also this number will increase.

This congestion of the orbital environment creates significant challenges for the safety of space-based assets: A collision with another spacecraft or a debris could severely damage a satellite or even destroy it resulting in significant disruptions to services. That is why the risk of such collisions and the potential damage from objects re-entering the Earth’s atmosphere are a growing concern.
To address these risks, an efficient system for surveying and tracking such objects and providing this information to stakeholders that depend on them to protect their assets is essential.
An SST system means a network of ground-based and space-based sensors capable of surveying and tracking space objects, together with processing capabilities aiming to provide data, information and services on space objects that orbit around the Earth
What is EU SST?

EU SST is a subcomponent of the Space Situational Awareness (SSA) component of the EU Space Programme. It safeguards space assets, especially EU Space Programme satellites such as Galileo, EGNOS, Copernicus, GOVSATCOM and in the future IRIS², along with the space assets of EU Member States and other space operators.
EU SST uses a network of ground-based sensors capable of surveying and tracking space objects and processing capabilities that help to improve, operate, and provide data, information and services on space objects orbiting the Earth. This helps to mitigate the risk of a collision between satellites and debris, in-orbit fragmentations and uncontrolled re-entries into Earth’s atmosphere.
How does EU SST work?
The Constituting National Entities of 15 EU Member States (Austria, Czech Republic, Denmark, Finland, France, Germany, Greece, Italy, Latvia, the Netherlands, Poland, Portugal, Romania, Spain and Sweden), together forming the EU SST Partnership, have networked their national assets (radars, telescopes and lasers) into the EU SST system.
Thanks to the work in the EU Industry and Start-ups Forum (EISF), the sensor network of national EU SST assets is complemented by commercial assets, thereby achieving better coverage, redundancy, and data provision. Check out the latest map of both national and commercial EU SST sensors here.
What services does EU SST provide?
In cooperation with the SST Front Desk at the EU Agency for the Space Programme (EUSPA), EU SST provides three services:
- Collision Avoidance (CA)
Collision Avoidance (CA) provides risk assessments of potential collisions between spacecraft or between spacecraft and space debris, generates collision avoidance alerts, and analyses all available information to detect close approaches with different levels of risk
- Re-entry Analysis (RE)
Re-entry Analysis (RE) provides risk assessments of uncontrolled re-entries of space objects and space debris into the Earth’s atmosphere, and generates related information including the estimated timeframe and likely location of possible impact
- Fragmentation Analysis (FG)
Fragmentation Analysis (FG) provides the detection and characterisation of in-orbit fragmentations, break-ups or collisions, and analyses all available information at short, medium and long term regarding the object(s) involved in the event.
EU SST also works on the development of two additional services:
space debris mitigation to reduce the generation of new space debris
space debris remediation to better manage existing space debris
What is the EU Industry and Start-ups Forum (EISF)?

EU SST supports the development of EU industrial SST capabilities. This helps to boost the competitiveness and innovation of theEU SST private sector,support the rapidly growing demand for anddevelopment of new SST services, and improve and consolidate the autonomy of EU SST in all orbit regimes beyond the network of existing national assets.
The EISF, co-chaired by the Commission and the EU SST Partnership, defines together with EU stakeholders incl. start-ups, SMEs, midcaps and large companies (and some EU research and technology organisations) research and development priorities for the Union’s SST domain.
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