Observatory Online: Measuring Distances With Redshift

Astronomers can measure the distances to the most distant reaches of our Universe, but none of the methods we've looked at so far can go much further than our nearest neighbouring galaxies. How do they push far beyond into the depths of the cosmos?

Royal Observatory Astronomer Ed talks about how, when it comes to the scale of the Universe, colour is everything.
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The Royal Observatory is the home of Greenwich Mean Time (GMT), the historic Prime Meridian of the world and London’s Planetarium.
Our astronomy science learning and public engagement team is made of real astronomers who are also professional science communicators.

The Royal Observatory is part of Royal Museums Greenwich, along with the National Maritime Museum, Cutty Sark and Queen's House.