Astronomical Instruments

An Instrument Cluster on the WHT telescope

Credit: Paul Langford (ING, La Palma)

When astronomers first used telescopes, they looked through them and drew or described what they saw.

However, with the invention of the camera, it became possible to take pictures through a telescope.

This means that not only can astronomers have a record of what they saw, but by using longer and longer exposure times, they can make measurements of fainter and fainter objects.

Nowadays, telescopes can have many different instruments, each for taking different sorts of measurements.

These instruments include:

• Photographic instruments.
• Electronic CCD cameras.
• Spectrographs for looking at all the different colours of light from an object.