Yes, it's true. You can damage your eyes by staring at the sun. People need to remember that as they turn to the skies to watch the silhouette of Venus march across the face of the sun on Tuesday from the Western Hemisphere (Wednesday from the Eastern Hemisphere.) Read more
A partial eclipse can be observed through special types of filters or shades that block the sun's harmful rays. Among the alternatives are No. 14 welder's glass and aluminised Mylar plastic manufactured specifically for solar observation. Experienced observers may use two layers of completely exposed and fully developed black-and-white photographic film, provided that the film contains a silver emulsion.
Types of filters that are considered unsafe include general-purpose sunglasses, smoked glass, developed color film and "space blankets." Read more