The FAST telescope is a radio telescope in the Guizhou province in China. It is the world’s largest telescope. FAST stands for Five-hundred-meter Aperture Spherical radio Telescope.

Construction of the massive telescope took more than 5 years. Scientists chose to build the telescope far from towns and villages. This reduces interference from electronic devices which produce radio waves, such as mobile phones. It was a huge engineering challenge to build FAST in such a remote location.

The FAST telescope has a similar design to the Arecibo Telescope. Both have a large dish built into the ground with a movable receiver hanging above the dish. FAST has a wider and deeper dish than the Arecibo telescope. This lets it observe more of the sky and detect fainter signals. Sections of the dish can move which allows FAST to track objects in space.

The FAST telescope collects radio waves from objects in space. It searches for pulsars and 'fast radio bursts' and studies the 'interstellar medium' (the space between the stars). FAST is part of the SETI project to search for signs of alien life. Scientists will also use FAST to hunt for the left-over shock waves from the Big Bang!

Scientists started using FAST to observe the sky in 2016. They spent 3 years testing it to make sure it worked. The telescope made its first discovery of two new pulsars in 2017.