Scientists in India used a special device called a Twilight Photometer to study the red light in the sky at sunset. They found different types of gases and molecules in the atmosphere, like nitrogen and oxygen, that create these red lights. The Twilight Photometer is a simple and cheap tool that can help us understand what's happening in the air above us every day. This study shows that the Twilight Photometer is a useful way to monitor the atmosphere and can give us important information about what's going on high up in the sky.