And on the seventh day, the wildfires rested. That’s what Australian researchers discovered after using NASA satellite images to track global fires—both naturally occurring and human-caused—from 2001 to 2013 as part of a new study. They found that there are fewer fires on Sundays—the Christian day of rest—in countries with large Christian populations, Colorado's Gazette reports. In countries that are home to mostly Muslims, where Friday is observed as a day of prayer, there are fewer fires on Fridays. "Our weekly routines are based on religion, originally," researcher Nick Earl of the University of Melbourne tells the Washington Post. "And you can see that in the weekly cycle of fires."
Overall, global fires drop considerably on Sundays and peak on Tuesdays, according to the study. Between 2001 and 2013, for instance, there were 104 million fires globally on Sundays. The total number of fires increased by 9 million on Tuesdays during the same period. Researchers speculate that people are less likely to start fires, including fires used for land management, on their days off, the Gazette notes. Earl tells the Post that linking instances of fire to the workweek, including days of religious observance, was the best way to explain the data. "If someone comes up with a different idea, that’s great, because I can’t think of one," he says. "I can’t think of any other reason for it." (Read more wildfires stories.)