Sir Isaac Newton once wrote, in what must be one of the most oft-quoted lines in the history of science, "If I have seen further it is by standing upon the shoulders of giants." Well, any of us ...

One of the biggest limitations of Galilean telescopes, with their combination of a convex and concave lens, was their narrow ...

In a ray diagram, a concave lens is drawn as a vertical line with inward facing arrows to indicate the shape of the lens.

Convex lenses have a wide range of uses, and are commonly found in: magnifying glasses spectacles for people with long-sight (who can see distant objects clearly but not nearby ones) telescopes ...

The outward curve of the lens should be facing the inside of the tube. Explain to your child that telescopes work by making objects that are far away appear closer. Have them practice by placing ...