Astronomy Glossary

Telescopes Equipment

A field flattener is a corrective lens that eliminates the curved focal plane inherent in many telescopes, producing sharp stars across the entire ima...

Telescopes Equipment

Specialized filters block light pollution and enhance contrast for emission nebulae by isolating specific wavelengths.

Telescopes Equipment

A finder scope is a small, low-power telescope or sighting device mounted on the main telescope to help locate objects in the sky.

Telescopes Equipment

Focal length is the distance from a telescope's primary lens or mirror to the point where light converges to form an image.

Telescopes Equipment

Focal ratio is the telescope's focal length divided by its aperture (f-ratio = focal length / aperture diameter).