Sunlight does not change its temperature as it travels through space to reach the Earth. The temperature of sunlight remains consistent as it travels from the Sun to our planet.
The Sun’s outermost layer, known as the photosphere, has an average temperature of approximately 5,500 degrees Celsius (9,932 degrees Fahrenheit). This is the temperature at which sunlight is emitted. As sunlight travels through the vacuum of space, it does not experience changes in temperature, because there is no medium to conduct heat.
However, when sunlight reaches the Earth’s atmosphere, it can undergo various interactions. Some of the incoming solar radiation is absorbed by the atmosphere, some is reflected back into space, and some reaches the Earth’s surface. The absorption and re-emission of energy by the atmosphere can influence local temperature patterns and weather, but it does not alter the fundamental temperature of sunlight itself.