ESOcast is a video podcast series dedicated to bringing you the latest news and research from ESO, the European Southern Observatory. Here we explore the Universe's ultimate frontier.
https://www.eso.org/public/esocast.html
ESOcast 63: Flexible Giants — The Evolution of Telescope Mirrors
The clear night sky offers one of the most beautiful views in nature. The eye adapts to the dark and the pupil widens to collect more light and thus allow fainter stars to become visible. But the light-collecting area of the human eye is tiny. To peer much deeper into the night sky astronomers need telescopes with enormous primary mirrors to do a much better job.