Building work starts on world's largest telescope
27 May 2017 Last updated at 14:42 BST
Building work has started on the European Extremely Large Telescope - the largest telescope in the world!
It's not in Europe though - instead it's being built on top of a mountain in the Atacama Desert in Chile, South America.
That's because the dry conditions of the Atacama make it the best place on Earth to look into space.
It's hoped it will be up and running in 2024 and will let astronomers see deeper into space than ever before.