Swedish-ESO Submillimetre Telescope

The Swedish-ESO Submillimetre Telescope is a radio telescope with a 15-meter diameter parabolic reflector at La Silla Observatory. It was designed to observe cosmic objects across frequencies ranging from 70 to 365 gigahertz, allowing it to study distant celestial sources in the submillimetre spectrum.

The telescope was established in 1987 and served as the only large submillimetre observation instrument in the southern hemisphere until operations ended in 2003. During those years, it made important contributions to astronomical research that would have been impossible elsewhere.

The telescope resulted from cooperation between the European Southern Observatory and the Swedish Natural Science Research Council. This partnership brought together researchers and engineers from different nations to build a shared instrument for astronomical research.

The instrument sits at 2375 meters elevation in the Chilean Andes, where atmospheric conditions throughout the year are favorable for astronomical observation. This high altitude combined with the dry mountain environment makes it an ideal location for submillimetre observations.

In 2022, plans emerged to relocate the instrument to the Gamsberg Nature Reserve in Namibia, where it would become Africa's first millimetre radio telescope. This move demonstrates how scientific equipment can be repurposed and bring new observational capabilities to different regions.