Scenarios of future annual carbon footprints of astronomical research infrastructures

TL;DR

This study analyzes the historical and projected future greenhouse gas emissions from astronomical research infrastructures, highlighting the dominance of space missions and the need for sustainable practices in the field.

Contribution

It provides a comprehensive inventory and trend analysis of emissions from astronomical facilities, emphasizing the importance of sustainable research practices.

Findings

Space missions dominate emissions, peaking in the late 1960s.

Emissions have decreased then increased again over recent decades.

Future emissions are likely to rise without changes in research practices.

Abstract

Research infrastructures have been identified as an important source of greenhouse gas emissions of astronomical research. Based on a comprehensive inventory of 1,211 ground-based observatories and space missions, we assessed the evolution of the number of astronomical facilities and their carbon footprint from 1945 to 2022. We found that space missions dominate greenhouse gas emissions in astronomy, showing an important peak at the end of the 1960ies, followed by a decrease that has turned again into a rise over the last decade. Extrapolating past trends, we predict that greenhouse gas emissions from astronomical facilities will experience no strong decline in the future, and may even rise substantially, unless research practices are changed. We demonstrate that a continuing growth in the number of operating astronomical facilities is not environmentally sustainable. These findings should motivate the astronomical community to reflect about the necessary evolutions that would put astronomical research on a sustainable path.