The ALMA radio telescope array at the Atacama Desert, Chile, releases close to 57,000 tons of greenhouse gases per year. Credit – Ronald Patrick/Getty Images
It is hard not to love the Kepler Space Telescope. The venerable spacecraft was launched in 2009 and discovered almost 5,000 exoplanets or worlds orbiting other stars during its 11-year lifespan. It was built and launched at a relatively low cost of $600 million. It produced 4,306 scientific papers by 9,606 authors. So it’s all good. It’s not so.
The telescope that discovered many other worlds also generated 4,784 tons of carbon dioxide annually over the 11 years. This was mainly due to the electricity and supercomputing that it required to operate. This equates to 12 tons of carbon dioxide per paper and five tonnes per author.
Astronomy seems to be the most straightforward of sciences in many ways. It is free to gaze at the sky. Both ground-based and space-based observatories have a significant environmental impact in terms of construction, launch and energy generation. And even, if you are not counting the time it took to fly from conference to conference around this globe, the estimated 30,000 astronomers.
Now, a New paper Astronomy of Naturehas taken the complete measure of the greenhouse gas emissions from skygazing. Researchers analyzed the total CO2 output from 46 space-based missions as well as 39 ground observatories. This data was dated back to the 62-year-old. Observatoire de Haute Provence, in the southeastern France and as recent as the new InSight observatoryNew Mexico’s online portal went online in 2017. In that time, the researchersaffiliated with the Institut de Recherche en Astrophysique et Planetologie (IRAP)Toulouse, France, concluded that the 85 observatories produced a staggering 20.3million tons of CO2 per year, an average of 1.2million tons.
Astronomers get distracted by the day-to-day. The next funding grant, the next project. Annie Hughes, IRAP astronomer was a coauthor of this paper at a March 17 newsconference announcing the results. Although our colleagues are aware that climate change is a problem, there is a lot of inertia within the system.
The paper, which was written by researchers over three years, used 2019 for the reference year and does not include new observatories like the James Webb Space TelescopeThe massive, or? Square Kilometer ArrayAustralia and South Africa are currently under construction. Other spacecraft not included in this work include the trio ships from China and the United Arab Emirates, which arrived at Mars 2021. The numbers are troubling enough even without the addition of new entries to Mars.
Ground-based observatories are dominated by the simple business of construction. This is because the concrete pouring phase of the CO2 emissions is the first phase. 600 kg (1.100 lb.) of CO2 are released Releases 600 kg (1,100 lbs.). of CO2 Each ton of cement used. 8% of all annual greenhouse gas emissions are caused by the cement industry.
The VLT [Very Large Telescope]ALMA and the ALMA [Atacama Large Millimeter/submillimeter Array]They are just incredibly expensive infrastructure and come with a huge carbon footprint, said Jrgen Kndlseder (IRAP astronomer) at the press conference.
It is also important to consider where you are located. The biggest CO2 contribution to a ground-based telescope comes from the electricity it uses to make its observations. The VLT and ALMA are not the only observatories that call Chile’s Atacama Desert home. It also hosts 14 other observatories thanks to its extremely dry air and 330 nights of clear sky each year. It makes for stunning viewing, but Chile ranks at the middle of the range when it comes to cleanliness of its electricity network.
Kndlseder said that Chile has an average electricity emission factor. It is not as high as Australia’s, which uses a lot more coal, but it is not as low as France and Sweden, which use a lot renewable energy.
Worse, remote observatories may not be connected to the electrical grids of their home countries and must generate their own electricity from diesel. ALMA, an example of such an observatory, released nearly 300,000.0 tons of CO2 during construction and continues to emit 56,154 tons annually.
Space-based observatories leave a smaller carbon footprint than terrestrial observatories. Their construction takes place in climate-controlled cleanrooms and hangars. Their greatest climate impact is the amount of electricity they use each year, which can add up over time. The Hubble space telescope, which is still in use and has been in service for close to 30 years, has released nearly 1.2 million tons CO2 during its lifetime. This is roughly 21 tons for each of the 52.497 papers that have been published about its findings. The James Webb Space Telescope launched on Christmas Day 2021 and could release more than 1.22 million tonnes of CO2 over its expected 20-year life span, according to the authors.
The paper emphasizes that the astronomy community must take drastic steps to reduce its carbon footprint, and not just consider it a cost of doing business. The total 20.3 million tonnes of CO2 that 85 observatories emit is equivalent to the annual greenhouse gas emissions of entire countries like Estonia, Bulgaria, Croatia, and Bulgaria. There are ways to lower those numbers.
Lyigi Tibaldo, IRAP astronomer, and co-author, stated that the first step is decarbonizing existing structures, using renewable energy sources. Solar power is feasible because the Atacama has abundant sun. The more that the energy grid, especially in Europe is dependent on renewables, the more telescopes will be able operate without a significant greenhouse effect. While most space-based observatories rely on solar panels to keep them running, a cleaner grid allows for their observations and data analysis with a smaller carbon footprint.
The authors suggest that we slow down the current building boom at observatories in Atacama and other locations, and rely more on the existing astronomical infrastructure. Tibaldo stated that we cannot achieve the strong reduction in emissions required for the next decade if we continue to build new infrastructure at the rate that we are doing now. This will give us more time for more thorough exploration of data from existing infrastructure.
The authors acknowledge that this is not a popular suggestion. Kndlseder said that some of our colleagues are shocked by the idea of slowing down. But there is more. [climate]The emergency we are currently facing is so severe that we believe this option should be considered.
The telescopes will continue to work, the astronomers will continue to observe, and the paper will continue being churned by the thousands. Academically at least that is a good thing. In the first paragraph of the paper, the authors note that Antnio Guerres, United Nations Secretary General, has warned the world that the IPCC report is a red alert for humanity. It is fine to search for and study new worlds. It is even more important to preserve and protect what we have.
