- Date: 1 May 2025
- Time: 0800 BT (UTC +2)
- Position: 050 46 2 N 000 43 9 E
- Course: 057 COG
- Speed: 6 SOG
- Wind: Var 1-2 bft
Happy May Day!
In addition to this important celebration, Twister is also marking an important moment, today: Early this morning, we will crossed the Prime Meridian, sailing from longitude west to longitude east. Without the Prime Meridian and the ability to measure longitude, we would not have known how far east we were from Saint Martin or the Azores on our journey to Amsterdam. So, I think this is a reason to celebrate the astronomers, mathematicians, and clockmakers across the ages and all around the world, on whose shoulders this innovation was developed. But why the clockmakers? Because in the end, it was the carpenter and clockmaker John Harrison, who in 1754 built the marine chronometer “H4”, which was able to keep the correct time on the voyage from England to the Caribbeans, despite the heaving, rolling ship and the vastly varying climates. With a watch with the correct Greenwich time on board, navigators were – and continue to be – able to know their longitude at the moment when the sun is due south for them, at their boat’s noon. With more calculations and the tables of the Nautical Almanac, the longitude can also be established at other times of the day and night. The H4 was the solution to the “Longitude Problem”, which had been the reason of many shipwrecks and lives lost, as well as a source of great uncertainty to navigators and trade. Why is the Prime Meridian running through Greenwich? Because that is where Charles II established in 1695 the Royal Observatory, as a centre for astronomical research. It became the reference location for the Nautical Almanacs. Today in the age of the Global Positioning System (GPS), using the sun, planets and stars to find your location is an interesting intellectual pastime for some sailors and a special aspect of their boating. It could also come in as a back-up should boat electronics fail. But more importantly, let’s not forget that the GPS, and with it any Google map on our phones, has the Prime Meridian together with the Equator as its foundation. So, we raised a glass – or rather a coffee mug – to the Prime Meridian, as we crossed 000°00.0.
Katrin
