Astronomy lovers in the United States will be treated to a partial disappearance of the sun behind the moon this Sunday (May 20). Only the Eastern Seaboard will be totally exempt. Over the course of the solar eclipse, the sun won't vanish completely, but will remain as a ring around the moon for what is known as an annular eclipse. When the eclipse occurs, the moon will be near its most distant point from Earth, making it appear smaller in the sky and thus unable to block the entire sun. But it will still be a stunning sight.

Thirty-three national parks will see the full effect of the moon's interference. Many western parks will be offering an array of events for their guests, ranging from placing telescopes out for viewing up to a full-scale astronomy festival.

"We're lucky that so many parks happen to lie within the path of the annular eclipse," Grand Canyon park ranger Marker Marshall told OurAmazingPlanet.