San José Observatory

San José Observatory (Observatorio San José, OSJ) is an amateur astronomy observatory in Buenos Aires, Argentina, and the oldest astronomical observatory in the city still in operation.

About San José Observatory

Founded by alumni of Colegio San José, the observatory today combines a working observation facility with a museum whose collections span acoustics, astronomy, electromagnetism, geodesy, meteorology, and optics and photography — a broad look at the physical sciences alongside its astronomical instruments.

History

The observatory was founded in 1913, though the building it now occupies was originally constructed in 1870. That combination of an older structure and more than a century of continuous astronomical use makes it a distinctive landmark among Buenos Aires observatories.

Telescopes & research

San José Observatory carries out research and public outreach, including online astrophotography courses with a deep-space specialisation, alongside its historic instruments and museum displays.

Location & getting there

The observatory sits in Buenos Aires, Argentina, part of our South America region listing, in the city that has hosted it for well over a hundred years.

Visiting San José Observatory

San José Observatory runs guided visits for schools and groups, and open nights that include lunar observation. For current schedules, courses, and booking, contact the observatory directly at [email protected] or via its official website.

See your named star from here

An observatory built around public open nights and lunar viewing is a natural place to point out a named star too — every star named through Star Register comes with its own right ascension and declination for exactly that purpose. Browse the catalogue or name a star of your own.