Hooker Telescope

The Hooker Telescope is a reflector telescope with a 100-inch primary mirror located on Mount Wilson in California. The instrument sits on a mechanical support system with a mercury flotation bearing that distributes its enormous weight and allows it to point anywhere in the sky.

This telescope began operations in 1917 and held the title of the world's largest working telescope for four decades. Astronomers including Edwin Hubble used it to make fundamental discoveries about galaxies and the universe's true scale.

The telescope allows visitors to engage directly with astronomical science and witness how researchers have shaped our understanding of the cosmos. Public observation sessions here connect people to the night sky and make research feel personal and approachable.

The telescope sits at an elevation of about 5,710 feet, so visitors should prepare for cooler temperatures and thinner air. Planning a visit here means dressing warmly and arriving ready for mountain conditions.

The mirror is held by 36 adjustable pressure points that keep it perfectly aligned no matter how the telescope rotates. This clever engineering lets the enormous mirror distribute its weight evenly while maintaining the precision needed for sharp observations.

GPS coordinates: 34.22515,-118.06440

Latest update: December 14, 2025 09:47