In my January column, I challenged readers to look for some of the finest naked-eye features on the Moon during lunar perigee — when the Moon is closest to Earth in its elliptical orbit. But have you ever wondered if we can tell whether the Moon is at perigee or apogee (when it's farthest away) using only our unaided eyes? The problem is that during the night the Moon sails across the vast vault o...
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June 2011: While you’re searching the skies, look out for these ghostly, hard-to-find targets.
Published: April 25, 2011 //
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