Watching the sky

Fulldome timelapse footage showing observations being carried out by ESO's VLT at the Paranal Observatory. All four unit telescopes are shown, from left to right: Antu, Kueyen, Melipal and Yepun. The laser light sent up to the sky by Yepun is part of the VLT's state-of-the-art Adaptive Optics system, which uses the laser as a "guide star" to correct the blurring effects of Earth's atmosphere, and create sharper images. Each unit telescope has a main mirror 8.2 metres in diameter, and can observe independently. When used together, however, they can see the night sky in sixteen times more detail than they can alone.