AT sunset

One of the Auxiliary Telescopes (AT) of ESO’s Very Large Telescope (VLT) is silhouetted against a dramatic sunset in this image taken from the platform at the Paranal Observatory. The ATs are 1.8 metres in diameter and feed data into the VLT Interferometer (VLTI) to produce even higher resolution images. They can be moved along tracks to various observing locations according to the needs of specific observing projects, making the VLTI more versatile.