Greenwich
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Matthew Pearson

10 Facts About The Royal Observatory Greenwich

We've rounded up 10 facts about the Royal Observatory Greenwich, including... 

  • Why it was established 
  • What you can see there today 
  • When and why its ball drops 

1. It owes a lot to one of the country’s most famous architects 

Before Sir Christopher Wren designed iconic landmarks like St. Paul’s, he was a professor of astronomy at Oxford University. It was under this role that he was selected by King Charles II to establish the Royal Observatory Greenwich. Wren then chose the site at Greenwich, thus setting the stage for the Observatory's grand history. 

Greenwich Royal Observatory

2. Before it, there was no standardised method for measuring time 

How does the Royal Observatory Greenwich set the time? Well, it's most famous for being the home of the Prime Meridian. This longitudinal marker is essentially Longitude 0, it standardised time in the form of Greenwich Mean Time (GMT). This changed the game for everything from navigation to global businesses. 

Standardisation was hugely beneficial when it came to mapping the night sky, with separate observation points able to be recorded in terms of their distance from the Prime Meridian. It was also incalculably useful in terms of seafaring, with distances, times and routes able to be mapped effectively because of the use of a standard longitudinal point. 

As the industrial world came into shape, trains, factories and global businesses could use Greenwich Mean Time as a universal measure of time, streamlining the timings of journeys, transactions and production periods across the whole planet. 

3. The Royal Observatory Greenwich has an amazing clock collection 

As a landmark of time and distance, you’d expect them to have a decent clock collection. And the Royal Observatory Greenwich doesn’t disappoint when it comes to their timepieces. The list of historic clocks — many of which revolutionised the way we record, measure and keep track of time across different industries—is lengthy.

Particular highlights include the Russian F.M. Fedchenko pendulum clock, which is said to be one of the most accurate such timepieces on the planet. The Shepherd Gate Clock mounted on the outer wall of the Observatory has an unusual 24-hour display. 

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Royal Greenwich Observatory

4. You can be sure of getting the right measurements at the Royal Observatory Greenwich 

The Royal Observatory Greenwich features a set of Public Standards of Length. Marked out by brass pegs, these measurements set out the exact length of different imperial measurement units, including a yard and a foot. So, if your shelf doesn’t fit once you’ve measured it up against the markers here, you’re doing something wrong!

5. Charles II created the position of Astronomer Royal 

As European exploration and international trade picked up, King Charles II was encouraged to establish an observatory that could aid in the understanding of astronomy and navigation. When founding the Royal Observatory Greenwich, he also created the post of Astronomer Royal. 

John Flamsteed became the first person appointed to the position. There have been only 15 Astronomers Royal since Charles II created the position in the late 17th century. You can learn all about them during your visit to the Observatory.

Greenwich Royal Observatory

6. The Royal Observatory Greenwich is very good at dropping the ball 

A bright red Time Ball sits on top of Flamsteed House, one of the main buildings of the Observatory complex. The ball rises to the top of its mast each day, beginning its ascent at 12.55pm, before dropping at exactly 1pm. 

Considered one of the earliest public time signalling devices in the world, it first dropped in 1833. Head to the Royal Observatory Greenwich to see the bright red ball drop...get there a few minutes before it lifts up at 12.55pm. Don’t be late. It doesn’t wait. 

7. It’s the place to go for stargazing in the capital  

While its research has moved elsewhere, the Royal Observatory Greenwich is still key for astronomy. Check out the Royal Observatory Greenwich astronomy exhibits, like the Peter Harrison Planetarium for some starry insights. 

8. You should explore the park – as well as the known universe – during your visit 

Back when the Observatory was primarily a scientific institution, it occupied a great expanse of what is now Greenwich Park. The views from the hill on which the Observatory stands are magnificent (and legally protected), with the Thames stealing the show and providing a backdrop for the historical National Maritime Museum. 

The area was once one of Henry VIII’s (many) favourite hunting grounds. You can still find deer (now in a protected enclosure to keep them safe from Big Hen), in a section of the park. 

Greenwich Observatory

9. It is part of the Maritime Greenwich World Heritage Site 

Yes, the Royal Observatory Greenwich is one part of a UNESCO World Heritage Site. The Maritime Greenwich World Heritage Site is a collection of attractions important to maritime history within central Greenwich and Greenwich Park.

These include the Cutty Sark, the last surviving tea clipper ship, and the Old Royal Naval College, a Baroque masterpiece. So set course to Greenwich without delay, Captain. 

10. It’s the centre of the world 

The Royal Observatory Greenwich Prime Meridian facts are impressive. It literally divides the world into the western and eastern hemispheres. Every point on Earth was measured in relation to its distance east or west of the Prime Meridian. 

Stand on either side of that line, and you're straddling the two halves of our planet.

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