Sustainability
Scientific excellence guided by long-term environmental responsibility
Sustainability is a core value of the WST, supported by a dedicated, cross-disciplinary group that develops guidelines, with particular attention to the design and construction phases.
“...it underscores our
responsibility to deal more
kindly with one another, and to preserve and cherish the pale
blue dot, the only home
we've ever known.”
- Carl Sagan
The “Pale Blue Dot” picture: the Earth was captured by the probe Voyager 1 on February 14, 1990. Credit: NASA/JPL-Caltech
“...it underscores our
responsibility to deal more
kindly with one another, and to preserve and cherish the pale
blue dot, the only home
we've ever known.”
- Carl Sagan
The rationale
Astronomy contributes to several of the United Nations’ Sustainable Development Goals (SDGs), as highlighted by the Office of Astronomy for Development. For example, it helps create jobs and benefits local economies in remote areas. At the same time, educational programs teach programming, data science, and STEM skills to underrepresented communities.
In addition to the benefits to society, astronomy has the responsibility to tackle another SDG: SDG 13, Climate Action. Astronomy relies on large-scale infrastructures that have a non-negligible environmental impact. These infrastructures are complex, energy-demanding, and often located in remote environments. Research infrastructures alone account for 36 tonnes of CO₂ per astronomer per year, nearly 18 times the Paris Agreement’s 2050 target of 2 tonnes of CO₂ per person per year. This represents roughly 17 round-trip flights from Paris to New York annually.
The WST approach
Within the WST consortium, we recognise that scientific progress must go hand in hand with environmental responsibility. We are therefore exploring ways to make this facility as sustainable as possible.
The ongoing initiatives include:
Assessing the environmental impact of the WST instruments:
The carbon footprint is indeed used as a trade-off parameter to inform the choice of design for the IFS and the two MOS.
After a few decades, the environmental footprint of large-scale infrastructure is typically dominated by operation, particularly energy consumption, due to the need to cool down detectors. Life-cycle assessments of the different design options, in particular for the IFS, are performed, confirming that after ~5 years, the instrument’s operational footprint dominates. CMOS solutions are usually preferred because detectors can work at higher temperatures with respect to CCDs, resulting, for the same design choice, in a ~25% decrease in the total carbon footprint.
Investigating different ways to deal with the very high amount of data expected:
We have also entered an era of “big data”, driven by advances in Artificial Intelligence and high-performance computing. The use of energy and water for cooling the data centres is considerable. The WST is expected to generate very large volumes of data, estimated between 1 and 3 PetaByte per year. We are therefore investigating ways to store and manage this data in the most environmentally responsible way possible.
Lead of the carbon footprint analysis. The plot shows the mean carbon footprint for 1 year of operation of the Integral field Unit in tons of CO2 eq. for different design choices. The carbon footprint associated with designs using CMOS detectors and CO2 plus Peltier cooling system is plotted in dark dashed line while the carbon footprint associated with designs using CCDs and Linear Pulse Tube cryocoolers are plotted with a light blue contour. Designs A,B, and D (light yellow) all have 144 spectrographs. Design C (green) consists of 128 spectrographs. Designs labelled as “Other” have 192 spectrographs. The error bars associated with the carbon footprint are visible.
Credits: Laurane FréourEncouraging discussions inside the working group on sustainability:
These challenges are being addressed through a dedicated working group, supported by the project office, with close collaboration between the sustainability working group and the Equity, Diversity and Inclusion (EDI) group to ensure that environmental responsibility and inclusivity advance together within the community. Beyond institutional efforts, astronomy contributes to broader societal well-being, which is considered one of the pillars of sustainability in a broader sense. In this regard, it can support mental health by fostering awe and a sense of belonging, promote gender equality through initiatives such as girls’ astronomy camps that encourage young women to pursue STEM careers, and support peace-building by bringing communities together in regions affected by conflict.
References
Knödlseder, J., et al., 2022, Estimate of the carbon footprint of astronomical research infrastructures, Nature Astronomy, 6, p. 503–513.
https://doi.org/10.1038/s41550-022-01612-3Mdhluli, J.E., et al. 2025, Astronomy as a strategic driver for sustainable development. Nat Astron 9, 936–939.
https://doi.org/10.1038/s41550-025-02602-x
We are aware that every new research infrastructure has an impact on the environment, and sustainability in astronomy is a complex challenge. By integrating environmental criteria early in the design process, we aim to better understand and reduce these impacts whenever possible.
The WST Operations Work Package is dedicated to designing the science-driven operational framework and data flow architecture that will enable WST to deliver its ambitious scientific goals.
Interview with Laurane Freour
Issue #2 The WST Chronicle"Sustainability should be taken into account as early as possible"