How do astronomers work?

Astronomers observe the night sky with huge telescopes. To protect the telescope, a circular 'observatory' is built all around it known as an 'observation station'. It is built in regions where it is pitch dark in the night and where there is very little mist or dust to hamper human vision. Telescopes not only receive light but also other wavelengths, such as radio waves, emitted by the stars. The larger the telescope, the more signals it can receive; one of the largest telescopes is present in Arecibo on the Caribbean island of Puerto Rico. It has a diameter of 300 m!