Many Iowans will slip into a warm sweater and head outside tonight to try and catch a glimpse of a falling star. One expert says it won’t be hard to do, as there’ll be plenty of them to see with the Perseid meteor shower underway. Iowa astronomer Doug Rudd explains why it’s an annual event. This meteor shower is the result of the comet Swift-Tuttle which passed through this area of space several years ago. It left behind a trail of rocks and debris which the earth is now passing through and those rocks are hitting our atmosphere and lighting up. Rudd says skywatchers should see as many as 60 meteors per hour — or about one a minute.He says to watch after ten P.M. in the east primarily, but they’ll be hitting all areas of the night sky. Telescopes and binoculars aren’t needed — just a lawn chair or a blanket, the naked eye and patience. You do -not- need to wear a hard hat. There are many thousands of these space rocks hitting the earth’s atmosphere, but Rudd says there’s little chance you’d be hit by one. He says when the comet passed the area it just shot off small pieces of debris.Rudd is president of the Des Moines Astronomical Society. The name of the meteor shower is derived from the way many of the meteors appear to originate in the eastern constellation Perseus.