Star rain down on the SEST

Stars rain down at La Silla Observatory in Chile. This image shows the now decommissioned (since 2003) Swedish-ESO Submillimetre Telescope (SEST) with a background of star trails caused by the apparent motion of the stars against the sky – caused by the rotation of the Earth on its axis.

The SEST was built on behalf of the Swedish Natural Science Research Council (NFR) and ESO. It was the only large sub-millimetre telescope in the southern hemisphere at the time of first light. It is very similar to the IRAM telescopes on the Plateau de Bure in France. It is superseded by APEX, and ALMA, on Chajnantor.