ATLAS · OBSERVATORIES · UNITED STATES
Observatories in United States
United States has 791 observatories on the map. 752 watch the night sky. 39 watch something else — the Sun, the radio sky, particles, Earth’s field, or a volcano. The earliest was founded 1830. Below: how they split by what they watch, and the country’s notable sites. From Wikidata, snapshot 2026-06-23.
OBSERVATORIES791
OLDEST FOUNDED1830
NOT WATCHING STARS39
By what they watch
Astronomical752 · 95%
Solar2 · 0%
Radio astronomy2 · 0%
Particle & cosmic3 · 0%
Geo & magnetic22 · 3%
Nature & bird3 · 0%
Volcano7 · 1%
Notable observatories in United States
A representative mix — the specialised sciences first, then the earliest sites by founding year.
Geo/magneticHonolulu Magnetic Observatory1902
VolcanoHawaiian Volcano Observatory1912
Geo/magneticWeston Observatory1948
Geo/magneticBoulder Geomagnetic Observatory1961
Geo/magneticLa Posta Astro-Geophysical Observatory1964
VolcanoCascades Volcano Observatory1980
VolcanoAlaska Volcano Observatory1988
ParticleHigh Resolution Fly's Eye Cosmic Ray Detector1997
VolcanoYellowstone Volcano Observatory2001
VolcanoCalifornia Volcano Observatory2012
NatureHornsby Bend Bird Observatory
NatureHanging Rock Raptor Observatory