
For 350 years Royal Observatory Greenwich has been a place where people come together to explore the universe.
Generations of astronomers spent countless nights looking up at the night sky, mapping the stars and measuring time. Their efforts gave us the Prime Meridian and Greenwich Mean Time (GMT), helping us find our place in the world.
But the story doesn’t end there.
Today almost one million people from the UK and around the world visit the Royal Observatory every year. It’s home to historic buildings and cutting-edge astronomy, precious instruments and London’s only Planetarium. A day out at the Observatory is a trip through time, a voyage round the globe and a journey into space – all rolled into one.
It's time to discover the next exciting chapter in the Royal Observatory's history.

First Light: bringing the wonders of the Universe to Greenwich
We are embarking on a landmark capital project to transform the Royal Observatory and make science and astronomy accessible to all.
The project, known as First Light, will bring the story of this historic site to life, and give everyone the chance to experience the wonders of space and time for themselves.
Inspiring galleries and displays, innovative architecture, sensitive conservation and improved access will all help unlock the Observatory's full potential.
The First Light project is named after the moment a telescope is first used to view and record the night’s sky. A telescope’s ‘first light’ is anticipated throughout its construction and is hopeful of future scientific discoveries.
This is your chance to be part of the Royal Observatory's story. Help protect a unique heritage site, and get ready to see the universe in a whole new light.
Impacts for visitors
The First Light project is set to begin in autumn 2025, with all work due to be complete by spring 2028.
During construction there will be some phased closures, beginning with the south side of the site. You can check all currently confirmed closures here.
The Peter Harrison Planetarium and the building it is in will be closed from Monday 8 September 2025. The rest of the Royal Observatory site, including the Prime Meridian line, Meridian Observatory and the galleries within the historic Flamsteed House, will still be open to visitors.
We will provide as much notice as possible about any future closures. Our astronomy teams are already working on plans to take their expertise and events out to the National Maritime Museum and the wider community – sign up to our newsletter to hear how you can join them!
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