Towards sustainable space research in France

Ten years ago, 195 countries signed the so-called Paris Agreement that aims to limit global warming within 2 degrees compared to pre-industrial time. According to the International Panel on Climate Change (IPCC), this objective can be only reached if anthropocentric greenhouse gas (GHG) emissions decrease to net zero by 2050¹. To achieve this challenge, all human activities, including scientific research, must become sustainable. In France, awareness on this topic is shared by a large fraction of the academic community². One third of the French research laboratories have already started evaluating their GHG emissions, using the public tool developed by Labos1point5^3,4. In 2022, the ethics committee of the French National Centre for Scientific Research (CNRS) stressed that “the environmental impact of research should be considered as part of research ethics, in the same way as respect of human beings and experimental animals”.

In this context, research performed using space-based instruments is facing formidable challenges. They make an unequivocal contribution to society by benefiting from the unique conditions of space. However, space missions have a large carbon footprint^5,6,7, notably because they need to be launched by rockets that are difficult to decarbonize. Rocket debris and satellite re-entries are also impacting the stratosphere⁸ and the ozone layer⁹. Nevertheless, in January 2024, CNES (the French space agency), together with 15 other French national research organizations, committed to “contribute, through their research activities and changes in their operations, to meet the challenges of the ecological transition for sustainability”. In particular, they decided to be “an example in the application of the objectives of [France’s] ecological plan”. The European Space Agency (ESA) also committed to “reducing [their] greenhouse gas emissions by 46% by 2030 compared to the 2019 baseline”.