Giant telescopes

Three of the four Unit Telescopes (UT) of ESO's Very Large Telescope (VLT) are pictured here on the platform at the Paranal Observatory. Each UT has a main mirror 8.2 metres in diameter, making them some of the largest single-mirror telescopes in the world. Also pictured, between the two UTs on the right, is one of the Auxiliary Telescopes, which have mirrors 1.8 metres in diameter. Uniquely for telescopes of this size, they can be moved along tracks to various observing locations to adapt to the different observing projects that are undertaken here.