A photographer in Sweden captured a dazzling green light in the sky, which was actually from Venus. Peter Rosen took the photo on January 8 and described how the cold atmosphere and sharp temperature difference over Stockholm created a prism effect, turning the light from Venus into a green flash. This natural phenomenon, known as a green flash, is typically seen at sea with a low, clear horizon when the sun sets or rises.”On Monday morning I woke up early to get a beautiful view of Venus and the Moon rising over Stockholm’s skyline. Because of the extreme cold that still persists over southern Sweden, I also got an unexpected bonus in the form of a rare green flash on Venus,” Mr. Rosen told spaceweather.com. Although green flashes on Venus are not uncommon, Mr. Rosen’s video of the event is considered one of the best ever recorded. The bright flash lasted about a second and has gained attention on social media platforms.The occurrence of green flashes is not limited to Venus, as the sun also emits similar green flashes, particularly when it rises. This is due to the refraction of light in Earth’s atmosphere, as the bending of light causes it to change speed and separate into individual wavelengths. For instance, the blue appearance of the daytime sky is due to the scattering of blue wavelengths more than any other color. Refraction also affects sound waves, with warmer air allowing sound to travel faster than in cold air. This explains why sounds can be heard much farther across water at night than during the day, as the cooling of the air over the water surface at night causes the sound to be refracted down by the warmer air layers above.
