Ariane 6 launches SIDLOC: opening up tools for safer space

Europe’s newest rocket soon launches, taking with it many space missions each with a unique objective, destination and team at home, cheering them on. Whether launching new satellites to look back and study Earth, peer out to deep space or test important new technologies in orbit, Ariane 6’s first flight will showcase the versatility and flexibility of this impressive, heavy-lift launcher. Read on for all about SIDLOC, then see who else is flying first.

SIDLOC (Spacecraft Identification and Localization) is an experiment from Greek non-profit the Libre Space Foundation (LSF). Their goal with the project is to help make space safer by speeding up the process of identifying space missions, from satellites to space probes and space stations.

Attached to the upper stage of the Ariane 6, the 63 x 63 x 40 mm SIDLOC experiment’s mission is to build an ‘open standard protocol’ to easily, automatically and accurately identify and locate spacecraft. It will do this via a radio-transmitted beacon, tracked and decoded by a network of open-source ground stations, software and hardware.

SIDLOC will transmit a broad-spectrum signal deliberately spread out over a large radio bandwidth. Information carried in the signal comes in a standard ‘schema’ – a structure and format consisting of binary data that is modulated to add all the necessary information about the spacecraft to the signal. The structured data format thus allows for the spacecraft's rapid identification and localisation.

On Earth, the SatNOGS Network – a global network of open-source ground stations – will receive the signal and demodulate the data, including the spacecraft's ID, and using the Doppler effect will identify the spacecraft's location.

In 2021, the Libre Space Foundation initiated an extensive study of the international space industry to identify challenges and vulnerabilities in launching new missions. Several challenges were identified revolving around the fast identification of spacecraft, system capacity and reliability, early pre-orbit functionality and immediate post-deployment activation as well as end-of-mission disposal solutions. The SIDLOC project was born to deal with these issues efficiently.

Rapid identification of missions in space helps enhance safety in orbit by reducing the amount of time that space is filled with ‘anonymous’ objects – important for collision avoidance and space traffic management. It also increases the chances of success for missions after launch and deployment as they can be quickly found, communicated with, tracked and controlled.

The Libre Space Foundation’s mission is to promote, advance and develop free and open-source technologies and knowledge for space, by designing, and developing space projects from ground station equipment to global monitoring networks and satellite missions and making all of the technologies involved publicly available. The SIDLOC project is no exception, with vast amounts of information about it available in open-source repositories.

“This is one of the basic principles that fuels our vision – making space available to all humanity,” explains Pierros Papadeas, Libre Space Foundation's Executive Director, “So, all Libre Space Foundation projects are open-source and strictly follow open-development methodologies. We believe this will increase SIDLOC’s positive impact, which is why the hardware we integrate into the Ariane 6 upper stage is both open-source software and open-hardware licensed”.

SIDLOC’s impact, once it is put to use, should be instant, enhancing safety in space as soon as it is implemented. More and more of humankind's infrastructure – scientific, Earth observing and communications – is now space-based. With increasing space activity in both the public and private realms, that space is getting crowded.

“By enabling fast and automatic localisation and identification of spacecraft, our infrastructure can become more resilient and efficient, and this is how SIDLOC's impact can have a positive impact for all,” concludes Manthos Papamatthaiou, Chairman of Libre Space Foundation and leader of the SIDLOC initiative.

“The SIDLOC experiment on Ariane 6 marks the debut of a technology poised to revolutionise Space Situational Awareness for years to come, potentially weaving itself into the very fabric of the space ecosystem.”