Here's a good article about the moon illusion from NASA's Science@NASA series "On Saturday night, June 30th, step outside at sunset and look around. You'll see a giant moon rising in the east. It looks like Earth's moon with the usual craters and seas, but something's wrong. This full moon is strangely inflated. It's huge! You've just experienced the Moon Illusion"...Read the whole article here http://science.nasa.gov/headlines/y2007/27jun_moonillusion.htm -- Jane Houston Jones Senior Outreach Specialist, Cassini Program JPL - 4800 Oak Grove Drive, MS 230-205 Pasadena, CA 91109 818-393-6435 jane.h.jones(a)jpl.nasa.gov Cassini SOC http://soc.jpl.nasa.gov/index.cfm What's Up? http://education.jpl.nasa.gov/amateurastronomy/index.html