Why are so many meteors exactly green? During the recent Perseid meteor shower, observers witnessed hundreds of green meteors. Photographer David Blanchard of Flagstaff in Arizona said that a green meteor flew right through the double star cluster h and x Perseus. He took this shot using a 30 second shutter speed on his Nikon camera.
Green is caused by oxygen in the Earth’s atmosphere. When a meteoroid flies through the atmosphere, the air in its path becomes so hot that oxygen molecules lose one of their electrons for a short time. Fast recombination occurs, a side effect of which is green photons. A similar process is also responsible for the green color of many auroras. This meteor also has a yellow streak – when a sodium-rich meteoroid pierces the atmosphere, hot sodium vapor glows yellow, as in a sodium discharge lamp.