Secrets of the Royal Observatory: we get an insider's look

Paul Miller from the Visitor Experience team at the Royal Observatory Greenwich spills the beans on all his favourite exhibits, historical heroes, and a few out-of-this-world surprises.

Published: June 19, 2025
The royal observatory greenwich

Atop the hill in Greenwich Park sits one of London’s most historic and literally groundbreaking institutions: the Royal Observatory. It’s where time began (GMT, anyone?), where telescopes reach for the stars, and where clocks tick with centuries of precision. But what’s it like to work at such a world-renowned spot? 

We caught up with, a member of the Royal Observatory’s Visitor Experience team, for a behind-the-scenes look at what makes this place tick – and no, it’s not just the clocks. 

What’s your favourite thing to see at the Royal Observatory? 

 “It’s impossible not to start with John Harrison's marine timekeepers,” he says. “These 18th-century clocks were made to work at sea so navigators could calculate longitude. They’re probably the most important timepieces ever made – maybe even the most important machines. And they still work!” 

He’s just as enthusiastic about the Great Equatorial Telescope. “It’s 28-feet long, with a 28-inch lens – the largest refracting telescope in the UK. It barely fits inside its dome, so it looks even bigger, almost vertiginous – like something out of Alice in Wonderland.” 

And, of course, there’s that famous line. “The Prime Meridian of the World – defined by George Biddell Airey’s Transit Circle telescope. It might just be a line on the ground, but it’s incredibly powerful.” It definitely has the power to get visitors throwing shapes of all sorts, trying to get the most creative pics, something we are sure Paul gets to see a lot of. Find out what the big deal is about the Prime Meridian! 

the greenwich meridian line

Gotta get that either side of the Meridian Line shot.

Any hidden gems people often miss? 

If you think astrolabes are obscure, Paul’s here to set you straight. And for those who don’t know what that is (don’t worry I didn’t either) an astrolabe is an ancient astronomical tool used to work out the position of the sun and stars, tell them time and do various other calculations. 

“We’ve got the fourth largest collection of astrolabes in the world,” he says. “These handheld devices were used for nearly 2,000 years – they’re arguably the most important astronomical tools ever made.” 

One, from the 13th century, made by an astronomer called Mahmud ibn Shawka, “was twisted out of its original shape to match the slow change in the Earth’s axis so it would stay accurate, even centuries later.” I mean, that level of precision in an age before Google Maps is mind-blowing. 

Another underrated marvel? James Bradley’s Zenith Sector telescope. “It looks rather unassuming, but it helped prove the Earth does, in fact, move around the Sun – two hundred years after Copernicus suggested it.” Further proof that sometimes the quietest exhibits have the loudest stories. 

the royal observatory dome

If you're lucky, you'll get to see the Dome open and peep the telescope!

Have you ever had a real “wow” moment at work? 

“Oh, all the time,” Paul says. 

“The wows almost always come from the visitors, we meet experts in various fascinating fields - astronomers and horologists, navigators and astronauts, engineers and surveyors.” 

One moment that really stuck with him involved a conversation with a family from Iran. “We’d been talking about the Prophet Muhammad’s journey through the heavens and Dante’s Paradiso, and they wrote out a selection of ayat for me. They were beautiful verses and I still reference them on my tours.” 

Do people have any misconceptions before they visit? 

“A big one is the surprise at how many clocks we have!” Paul says. “The idea of astronomers using ‘rational’ science to answer big questions is a relatively recent one, but for as long as humans have stood upright, they have used astronomy to measure and understand time-as well as to foretell the future, of course...” 

The Observatory’s star-studded timepiece collection includes everything from Thomas Tompion’s 13-foot-long pendulum clocks to the Shortt Free Pendulum, “which proved 250 years later that the Earth’s rotation isn’t as constant as we once thought!” 

Also surprising? “The Observatory was founded to support navigation. We still have a first edition of the Nautical Almanac from 1767 – and it’s still being published.” 

A clock at the royal observatory

That's one impressive looking clock!

Which historical astronomer would you most like to meet? 

Paul’s short list reads like a celestial dream dinner party. 

“Edmond Halley – not just for his groundbreaking work, but because he clearly knew how to have a good time.” 

He also champions Alice Everett, one of the first professional female astronomers. “She worked here in 1890 and was the first female secretary of the British Astronomical Association. Her research on the mirrored drum helped lay the foundations for television.” 

And then there’s Benjamin Banneker. “The first African American astronomer – and the surveyor for the project that established Washington D.C. as the capital. In addition to its obvious historical importance, Washington is home to some very intriguing and rather mysterious astronomical effects...” 

a clock at the royal observatory with visitors

Seriously, they know their clocks!

What else do you love in Greenwich? 

 “The Royal Observatory is part of Royal Museums Greenwich, along with the National Maritime Museum, Cutty Sark and Queen’s House. Each one’s brilliant on its own, but together they tell an incredible story of Britain, the sea, and the stars.” 

And the view from the hill? “Honestly – it’s breathtaking. Inigo Jones’ Queen’s House, Wren’s Old Royal Naval College, the Thames winding around Canary Wharf – it’s like seeing past, present and future all at once.” 

Plan your visit 

Ready to walk the Prime Meridian, marvel at 18th-century time machines, and twist your own perspective on the universe? The Royal Observatory is a must-see for curious minds, history buffs, and stargazers of all stripes. Paul might even be there to show you his favourite astrolabe – if you ask nicely. 

Enjoyed this?  

Check out our cheats guide to space and time or discover what the big deal is about Prime Meridian.   

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Alice Padfield
Alice Padfield
Content Manager

Alice is a copywriter in the Content team at Go City®, where she combines her love for travel, literature, food and theatre to craft inspiring content for cultural explorers. From blog articles to TikToks, she creates engaging stories that help travellers uncover hidden gems and must-see spots in every city. Passionate about exploring new destinations, Alice shares her discoveries to help others curate unforgettable itineraries.

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