Why, in the photo above, does Venus show rainbow-like colors? The reason is that Ilija caught Venus when it was low in the sky, where we’re looking at it through a greater thickness of Earth’s atmosphere than when Venus is viewed higher above the horizon. The atmosphere splits the Venus light (really, reflected sunlight) into this colorful array. Les Cowley of the great website Atmospheric Optics told us this morning:
Venus, and stars, close to the horizon certainly show prismatic colors from differential atmospheric refraction.
Bottom line: Maybe you didn’t realize Venus can appear as a crescent, much less in rainbow colors? These effects happen when Venus draws near its time of passing between us and the sun, which it will on June 3. You need a telescope (in the case of the crescent) and a camera (in the case of the rainbow colors) to capture them.
Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.