Observatory Types

Giant Optical Telescopes (8-40m)

Very Large Telescope (VLT), Chile
Keck Observatory, Hawaii
Gran Telescopio Canarias, Spain
Gemini North & South
Large Binocular Telescope, Arizona
ELT (39m, building), Chile

Radio Telescopes

FAST (500m), China
Green Bank Telescope, USA
Very Large Array (VLA), USA
Effelsberg (100m), Germany
Parkes (64m), Australia
MeerKAT, South Africa

Millimeter/Submillimeter

ALMA, Chile
NOEMA, France
IRAM 30m, Spain
Submillimeter Array (SMA)
APEX, Chile
South Pole Telescope

Gravitational Wave Detectors

LIGO Hanford, USA
LIGO Livingston, USA
Virgo, Italy
KAGRA, Japan
GEO600, Germany
LIGO-India (building)

Neutrino Observatories

IceCube, South Pole
Super-Kamiokande, Japan
SNOLAB, Canada
KM3NeT, Mediterranean
Baikal-GVD, Russia
Baksan, Russia

Survey & NEO Telescopes

Vera C. Rubin Observatory (LSST)
Pan-STARRS, Hawaii
Zwicky Transient Facility
Catalina Sky Survey
ATLAS (asteroid survey)
Spacewatch, Arizona

Interactive 3D Globe

Explore all observatories on a rotating globe. Click any telescope to see details, photos from Wikipedia, and local time.

Telescope Information

View mirror size, operating organization, coordinates, and photos for each observatory.

Multiple Types

From optical and radio to gravitational wave detectors, neutrino observatories, gamma-ray telescopes, and cosmic ray arrays.

Historic Sites

Discover historic observatories: Royal Observatory Greenwich, Paris Observatory, Mount Wilson, Yerkes, and more.

Frequently Asked Questions

What is the largest optical telescope?

Currently, the Gran Telescopio Canarias (10.4m) and Keck telescopes (2x10m) are the largest. The ELT (39.3m) is under construction in Chile and will become the world's largest when completed.

What is the largest radio telescope?

FAST in China has a 500m diameter dish, making it the world's largest filled-aperture radio telescope. The former Arecibo (305m) collapsed in 2020.

Why are many telescopes in Chile?

The Atacama Desert in Chile offers some of the best astronomical conditions on Earth: high altitude, dry air, clear skies, and minimal light pollution. ESO, ALMA, and many others are located there.

What is LIGO?

LIGO (Laser Interferometer Gravitational-Wave Observatory) detected gravitational waves for the first time in 2015, confirming Einstein's prediction. It has two 4km detector arms in the USA.