We know that social distancing helps slow the spread of COVID-19. Researchers are now looking at other environmental factors that can slow down COVID-19, such as different seasons and exposure to sunlight (specifically, ultraviolet, orUV, light from the sun). After looking at data from over 170 countries, they found that COVID-19 spread is lower in the weeks after more UV exposure. Also, recent studies show that UV light makes the virus that causes COVID-19 inactive on surfaces. Researchers found that, in the Northern Hemisphere with summer sunlight COVID-19 growth rate decreased by 7 percentage points compared to darker winter days. This suggests that COVID-19 spread may change by season, spreading faster in the winter when it is darker than in the summer. Why is this? It could be because people get more vitamin D from the sun in the summer, which could protect against COVID-19. It could also be because people are outside more in the summer where there is less risk of getting COVID-19 compared to indoors. Regardless, sunlight exposure alone is unlikely to stop the virus without social distancing, wearing face masks, and washing hands frequently.