Guide Star tracks in the Chilean sky

This image shows the paths swept out by the 4 Laser Guide Star Facility on ESO's Very Large Telescope (VLT) as it tracks an object throughout an observation. The four powerful lasers form a crucial part of the adaptive optics systems on the VLT and are the most powerful laser guide stars ever used for astronomy.

Adaptive optics systems allow astronomers to vastly reduce the atmospheric distortion present at even the best sites in the world for astronomy, including Paranal in Chile, the home of the VLT.