Astronomers Celebrate “Celestail Pollution” From Perseid Meteor Shower
This weekend, as millions of people gaze up at the stars and wait for Perseid meteors to streak across the sky, one would hardly think that these awe-inspiring “shooting stars” are also a source of atmospheric pollution.
However, meteors, like those from this month’s Perseid meteor shower, burn up high in the Earth’s atmosphere leaving behind gases. “It’s a form of natural pollution,” says Gemini Observatory’s Chad Trujillo who heads up the facility’s state-of-the-art Adaptive Optics (AO) program.
“One of the gases left behind by meteors is sodium, which collects in a layer about 60 miles (90 kilometers) above the Earth,” says Trujillo (see animation). “The reason astronomers are so fond of this particular pollution layer is because we can make it glow by using a sodium laser to excite this sodium and produce temporary, artificial stars wherever we like. Believe it or not,” jokes Trujillo, “there aren’t enough stars in the sky for astronomers!”
Full Story: http://www.gemini.edu/node/12050