Leoncito Astronomical Complex

The Leoncito Astronomical Complex is a research facility at 2552 meters elevation housing several advanced telescopes, including the Jorge Sahade telescope with a 2.15-meter diameter mirror. The instruments are designed so that scientists can operate them remotely from their own institutions.

Argentina's National Council for Scientific and Technical Research established the observatory in 1983, with official operations beginning in September 1986. The facility was placed at this mountain location because the elevation and dry climate provide ideal conditions for continuous astronomical observation.

The complex attracts thousands of visitors annually who participate in educational programs, joining daytime tours or evening observation sessions. Guests can experience astronomy firsthand and learn how scientists use these tools to study the night sky.

Scientists using the facility must submit detailed research proposals to an access committee for approval. Visitors without a research agenda can join regular guided tours that provide an overview of the complex and its operations.

The location enjoys more than 250 cloudless nights yearly, enabling continuous astronomical observation with minimal weather interference. This exceptional frequency of clear skies makes the site one of the best ground-based astronomy locations in South America.

Location: San Juan Province

Location: El Leoncito National Park

Official opening: September 12, 1986

Elevation above the sea: 2,552 m

Website: http://casleo.gov.ar

GPS coordinates: -31.79860,-69.29560

Latest update: December 10, 2025 20:01