University of Tokyo Atacama Observatory, Astronomical telescope at Cerro Chajnantor, Atacama Desert, Chile.

The University of Tokyo Atacama Observatory is an astronomical facility with a 6.5-meter telescope equipped with infrared detection systems and adaptive optics technology. The instrument is located on Cerro Chajnantor in the Atacama Desert at approximately 5,640 meters elevation.

Site planning for the facility started in the late 1990s, with road construction to Cerro Chajnantor beginning in November 2005. The project took years to complete as it required building access routes to one of the world's highest observation sites.

The facility represents a partnership between Japanese and Chilean scientific institutions working together on astronomical research. This collaboration shows how countries can share their research strengths across borders.

The observatory is not open to visitors; the summit is reached by a road built to Cerro Chajnantor between 2005 and 2006. Astronomers work remotely from a base facility completed in November 2014 at San Pedro de Atacama, about 50 km away, because of the altitude sickness risk at 5,640 m.

The telescope features a silver-coated primary mirror that allows observations with minimal atmospheric water vapor interference. The extreme dryness and elevation of the location make it one of the world's best sites for infrared observations.