by Rohan Sinha (’23) | April 8, 2022
In a study recently published in Nature Astronomy, scientists have revealed astronomical research’s contribution to climate change—also called its carbon footprint. According to their findings, the carbon footprint of research in the field of astronomy stands out from that of research in other fields. Lead author of the study Jürgen Knödlseder compared the carbon footprint of astronomy research to “the annual carbon footprint of countries like Estonia, Croatia, or Bulgaria.” This discovery has significant implications for the nature of scientific research itself.
The researchers involved in this study deviated from the method typically used to calculate a carbon footprint, the Life-Cycle Assessment (LCA), which measures the carbon footprint of a product by assessing its carbon emissions over different periods of its use. However, this strategy would require scientists to obtain detailed information about infrastructure like observatories and telescopes, which is typically confidential. Instead, researchers opted for a different approach: economic input-output (EIO) analysis.
Knödlseder explained, “The method that we used [EIO] assumes that greenhouse gas emissions of astronomical research infrastructures are proportional to their costs or their weight.” In other words, the researchers assumed that the cost of astronomy infrastructure, like telescopes, could provide information about their carbon emissions. Knödlseder provided an analogy to explain EIO analysis: “[J]ust think about what happens when you double the amount of fuel that you fill in your car’s gas tank. It will cost you twice as much, you will double the weight that your gas tank carries, and when you dry your gas tank empty, you will emit twice as much greenhouse gas into the atmosphere.”
Although this cost-based approach likely overestimates astronomy’s carbon footprint, the result allows for astronomical facilities to analyze their approximate carbon footprint and act accordingly.
Based on their findings, the researchers called for several changes in the methods of astronomy research, including a switch from nonrenewable fossil fuels to alternative renewable power sources. However, this change may be difficult to implement depending on the geographic location of observatories.
The physical scale of astronomical infrastructure has also grown rapidly, further contributing to an increase in its carbon footprint. Consequently, researchers also called for the implementation of “slow science.” Luigi Tibaldo, a co-author of the study, explains that one way to keep the increase in average world temperature within 1.5 degrees Celsius is to “reduce the pace at which we build the new infrastructures.”
At the same time, the researchers encourage more complete usage of data already available from observatories and telescopes. “Slow science” is not without its critics, however. John Mather, project scientist of the James Webb Space Telescope, stated that astronomy as a field has already become more difficult to study because of “light pollution, radio interference, and satellite constellations.” As a result, he argues that scientists need to maximize their ability to learn before they are no longer able to do so. Whether or not astronomers adopt “slow science,” this study has opened the door for important future climate research.
