Can a global pandemic affect temperatures on the Moon? A 2024 study linked worldwide lockdowns with a drop in heat radiation reaching the Moon from Earth – but now scientists say that wasn’t actually what was going on.
Here’s the original hypothesis from last year: As businesses closed their doors in 2020 and we all spent more time at home, carbon emissions dropped and there was a drop in terrestrial radiation – the heat being generated by our planet, and taken up by the Moon.
Previous research has raised the question of terrestrial radiation influencing lunar surface temperatures – and indeed there was an observed drop in Moon nighttime temperatures across April and May 2020, when many lockdowns were in force.
In the latest study, researchers from the Missouri University of Science and Technology (Missouri S&T) and the University of West Indies (UWI) wanted to take a closer look at the data – and found some problems with the link between COVID-19 and lunar temperatures.
“The idea that our activity, or lack of activity, on Earth would have significant influence on the temperatures of the Moon – which is almost 240,000 miles from us – didn’t seem likely, but we decided to keep an open mind and conduct additional research,” says civil engineer William Schonberg from Missouri S&T.
Looking at the data, the researchers found some problems with the original hypothesis. First, there was a dip in lunar temperatures in 2018 similar to the one in 2020, and a steady decline from 2019 – which doesn’t quite fit in with the timing of the pandemic and its lockdowns.
In fact, the temperature readings gathered by NASA’s Lunar Reconnaissance Orbiter suggest cyclical fluctuations rather than one distinct dip, according to the updated analysis. The researchers also point to a 2021 study which found that any emissions reduction linked to COVID-19 only affected the lower parts of Earth’s atmosphere.
“We’re not disputing that the temperatures did go down at different times during the time frame studied, but it seems to be a bit of a stretch to state with any certainty that human activity was the primary cause of this,” says Schonberg.
The researchers behind the new study also raise the possibility that fewer pollutants and a clearer night sky would actually increase the heat being reflected back from Earth to the Moon – potentially raising rather than reducing lunar temperatures.
There are of course a multitude of factors at play here, but the conclusion of the new study is that shifts in human activity are unlikely to have an impact on the temperatures on the Moon – during COVID-19 or any other period.
“During the Moon’s nighttime, there is a small possibility that heat and radiation from Earth might have a very small effect on the lunar surface temperatures,” says Schonberg.
“But this influence would probably be so minimal that it would be difficult to measure or even notice.”
The research has been published in the Monthly Notices of the Royal Astronomical Society: Letters.
