Reported January 2008

HOW PALOMAR AND OTHER TELESCOPES WORK: A telescope, in its most basic form, is a long tube with a lens on either end that magnifies distant objects. One lens is concave, the other convex, and the light that enters bends, or refracts. The concave lens collects as much light as possible, and a convex lens redirects the rays so that they all converge back to one point. And that point is where you get an image of any object in front of the lens. The reason we have difficulty seeing objects that are far away is they don't take up sufficient space on the eye's retina for the retinal sensor to detect them. A 'bigger eye' would enable us to collect more light from the object to create a brighter image, and then magnify part of it so that it stretches over more of the retina. A telescope is an extension of the human eye; in this case, it gathers light from dim, distant objects in the sky so we can see them more clearly.

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