Today the interest in orbital rendezvous, proximity or capture operations is growing rapidly. Accordingly on 5 October ESA published our Guidelines for Safe and Sustainable Close-Proximity Operations (CPO). The document’s objective is to present design principles meant to increase the safety of CPO.

The set of proposed guidelines and design principles are the outcome of the work performed by the ESA technically led CPO Working Group with the European stakeholders’ participations (space system integrators, space equipment suppliers, operators, insurers, national agencies, and Universities).

Historically, CPO missions have involved human-in-the-loop activities, such as spacecraft dockings and satellites retrievals via the Space Shuttle. However, the coming wave of In-Orbit Servicing (IOS) missions appear to be commercially driven and do not involve humans in the process – meaning there will be no astronauts in the vicinity to check that everything goes well! The high international interest for execution of rendezvous, proximity, and capture operations for non-human rated missions highlighted the lack of clear and widely accepted technical and safety standards in this domain, mainly because: 

  • The operations are involving highly complex systems and processes 
  • The “know-how” and associated technologies to perform rendezvous and capture requires identification of knowledge and technological gaps first followed up by e.g. feasibility studies, R&D activities 
  • There is a lack of technical requirements and verification methods
  • Current satellites are not prepared to be repaired, refuelled or tugged 

Since December 2019, ESA has been leading a Close Proximity Operations Working Group with European participation with the aims of drafting design guidelines and best practices to ensure safe and responsible proximity operations.  The objectives of the Working Group were to:

  • exchange information at European level to ensure a level of playing field for all stakeholders (e.g. national space agencies, system integrators and suppliers, operators, insurers, universities)
  • define a CPO glossary/boundary of applicability
  • prepare the safety/sustainability guidelines (e.g. technical, operational, verification & validation) for non-human related missions involving rendezvous up to capture
  • provide visibility of the results of CPO-WG activities to the European space community and industry
  • contribute to the development of worldwide Rendezvous and Proximity Operations and On-Orbit Services implementation standards in the framework of ISO 24330

The Guidelines detail the current technical understanding and agreement of European stakeholders on CPO, serving as a baseline for future technical discussions. To learn more about the rationale, the methods to assess compliance and the mitigation measures, a handbook will be soon prepared and made available to the public. 

The Guidelines are available on request by sending an email to cleanspace@esa.int

Related content

Watch CleanSpace’s webinar on “European Technical Recommendations for Safe and Sustainable Close Proximity Operations In-Orbit” to learn more about the technical guidelines ESA has been working on as well as the process and methods used to derive them.