Dancing with the Planets in the Pale Blue Moonlight - Exclusive Access at the ROG - 4 December 2025

On arrival at the gates of the world-famous Royal Greenwich Observatory, a minibus awaited us to take us uphill on the winding slope to the observatory complex.

With some of us arriving a little early, we took in the fabulous sights of the London city nightscape from the Meridian courtyard, but as we did so, we realised we were bathed in the ethereal moonlight of a full moon hovering and smiling high above us... oh alright, it was probably city light pollution, but come on, let’s just go with the romantic version, shall we.

As the official start of our much-anticipated tour began, our hosts, veterans Mike Meynell and Clive Inglis, and newcomer hosts, Amy Scammell and Alec Knox, emerged out of the shadows into the moonlight to welcome us and shepherd us, wayward but excited herd. We were then split into two groups to meet the requirements of maximum people allowed in parts of the tour.

My group was to first get a guided tour from Mike inside the Octagon Room, the Harrison Clocks and the Meridian Building. As he began the tour, he pulled out some notes and apologised that he would be reading a lot from them which is “perfectly alright”, we all chimed, and that he was recovering from the ‘flu. “Er, no problem!” we responded, rapidly taking ten paces back. Mike quickly followed up with “I haven’t got the flu now!”, to which we replied “er, sure,” tentatively taking five paces forward.

Mike began with an intro explaining that the observatory was founded in 1675 to improve navigation and solve the Longitude problem... the what problem? Alright, quick summary, it was easy for seafarers to know where they were latitude-wise, i.e. between North and South using the clockwork movement of the stars and moon, but to calculate their longitude positions between East and West, they needed accurate timekeeping. However, their best methods were too inaccurate by several degrees, resulting in many lost ships, accidents, and arriving at wrong destinations (I know that feeling, it was demoralising when I took a Northern Line to Kennington last week, only to find myself in Morden).

Our first stop was the Octagon Room in Flamsteed House, designed by the famous architect, Christopher Wren. Here, Mike narrated the work of John Flamsteed, the first Astronomer Royal entrusted by King Charles II with finding an accurate solution to the problem. It was the start of an epic saga through the centuries. But Flamsteed was never to find that solution in this room, as architecturally beautiful as it was - the 8 walls (hence the name, right?) with telescopes pointing out of a few windows are not even facing the meridian, which would have helped. Mike even said that it was built on the cheap, re-using previous foundations of an older building and costing almost the same as the miniature prototype model! Huh. So, Mike swiftly moved us on.

Next stop, the Harrison Clocks room. Mike first drew our attention to a large painting of a nice, jolly-looking but distinguished fella. It was the portrait of Admiral Shovell, a seafaring war hero of the Nine Years’ War who was commandeering his fleet back home to England, only to end up plunging four ships into the treacherous rocks of the English Channel, including the flagship that he was on, perishing amongst 1300 men as stated on the plaques. Oh man, what a tragedy. I think we were collectively thinking “Come on Mike, raise our spirits, we’re feeling quite depressed now”. Mike then continued that he believes it was more like 2000 deaths. Great. How does he know this, anyway? It’s not the first time he defies written historical text with such confidence... hmm, I wonder.

But Mike was expertly telling an epic journey here, as he continued to narrate that it was the biggest ever British maritime disaster and was the catalyst moment that brought tremendous outrage, fuelling the urgency of solving the Longitude problem. This resulted in the setup of a significant monetary prize fund for the first person to solve this. We know that John Flamsteed didn’t nail an accurate enough solution... so enter left stage John Harrison, perhaps the greatest and most important clockmaker in history. Taking centre stage in the Time Room were some beautiful-looking clock mechanisms that Harrison built. Mike explained their progressive iterations in field tests to help navigators figure out their positions. After several years of refining the clocks, Harrison abandoned the clock approach despite improving the practicality and accuracy each time and took a different approach. He went small. Mike showed us Harrison’s next solution, a beautiful and elegant pocket watch. With the help of a master watchmaker and after several iterations and seafaring tests, a high degree of accuracy was finally achieved. The pocket watch saved the day, and Harrison got to claim his well-deserved prize, having started this journey 30+ years earlier to get there.

With our spirits lifted at this point of Mike’s epic story, we continued to the Meridian Building. Now that we can accurately determine Longitude, where shall we have a globally agreed Prime Meridian line representing 0 degrees Longitude? So here, we learnt of the progression in Longitude-measuring instruments and after much political to and fro-ing from different countries, it narrowed down to a friendly standoff (well, I hope it was friendly) between Britain and France for which they reached an agreement for the Prime Meridian to be in Greenwich, yay! With one caveat that we adopt the metric system... um, yay!

So, another happy ending. But as we reached the exit, Mike drew our attention to a portrait of another distinguished fella, Nevil Maskelyne, 5th Astronomer Royal. Mike had a serious, almost angry expression on his face. He asked us if any of us had read the book or film adaptation “Longitude”, based on the same journey that he was giving us a tour on. In that book/film version of the story, Nevil is portrayed as the villain, preventing John Harrison’s progress on his timepiece solution. Mike passionately defends Nevil as being victim of a story always needing a villain when Nevil was in fact a hero in creating almanacs based on lunar distances that navigators could use to determine Longitude within just over a degree accuracy. Good ol’ Nevil. Looking at Mike’s sad expression, I can’t help wondering if he knew him well.

And so, it is here we thanked 350-year-old Mike profusely for a highly enjoyable tour narrated brilliantly as an epic multi-century journey to saving lives and laying a foundation in safely navigating around the world on land and sea, with accurate timekeeping. Something that we all take for granted today.

We then entered the second stage of our session - out in the courtyards, three telescopes were set up and managed by Flamsteed hosts Alec and Clive, and ROG astronomers Gideon and Robert.

The skies were wonderfully clear, and we were first treated to glorious views of a green moon and a red moon... wait, what!? The sight of the starburst effect of Tycho crater, the standout high albedo of the Aristarchus crater, and the extraordinary long slithering Alpine Valley were certainly striking and beautifully resolved, but why the green and red colours? Well, it is almost a full moon, and a full moon is too bright to look at through a telescope eyepiece without light-reducing filters. And so, filters were used to reduce that light for more comfortable viewing. The red and green filters accentuate some features on the moon, but neutral colour filters could have also been used, and I suspect they lost that filter!

But the “star“ of the show was Saturn. Well, at first it was perplexingly dim, and no rings could be seen... until someone noticed dew on the lens! So, upon wiping the dew off with care, Saturn was now visible in all its glory and there were the unmistakable rings. However, the rings’ tilt was almost edge-on, so looked like a blade slicing the planet in half! Still a glorious sight and interesting to see the rings edge-on, which occurs every 13 years, apparently.

We also got to observe the big brother of our solar system, Jupiter. The distinctive two brown gas bands that almost look like an “equal” symbol painted on to the planet, and its four Galilean moons. I couldn’t make out any Great Red Spot so perhaps that was behind the planet at the time.

After thanking our Flamsteed hosts and ROG astronomers profusely for their time to educate and entertain us, all that was left was for the minibus to take us back down to the park gates, only to be told it was broken down! So, our adventure extended with a leisurely walk down the winding path, reflecting on our wonderful evening at the observatory, bathed once more in that glorious pale blue moonlight.