Where On Earth…

In a recent blog post I said how it was that here in the northern hemisphere on Earth we are approaching the longest day of the year and that our days would slowly be getting shorter again. I received a lovely comment on that, but the writer also said how they perhaps didn’t wish to be reminded of this quite yet, as winter seemed to have lasted a little longer this year! I assured them that it just happens and it will be becoming cooler again, just not yet. But as each day follows night and we are refreshed, so also must the Earth itself be refreshed through all the changing seasons. Some lives end, new lives begin and it is a cycle that I hope and pray will continue for a very long time yet. Global time was not managed or organised in the way it is today though, in fact time itself wasn’t known quite as it is now. That is because our measurement of time began with the invention of sundials in ancient Egypt at some point prior to 1500 B.C. However, the time the Egyptians measured was not the same as the time today’s clocks measure. For the Egyptians, and indeed for a great many years after, the basic unit of time was the period of daylight. We all know that time is is of a fixed duration, though as I have said in the past it can seem to drag on sometimes! Now seventy countries change their clocks for Daylight Saving Time, including most of North America, Europe and parts of South America and New Zealand whilst China, Japan, India and most countries near the equator do not. I still like using the terms ’Spring forward’ and ‘Fall back’, so that we remember which way to turn the clocks, although ‘fall’ is of course the American term for Autumn. In the past (and I am going back quite a while now of course) many of the inhabitants here on Earth believed that it was flat and we were the centre of the Universe. Perhaps a little bit like young children think they are, until they start to interact with others. But then so long ago we also began to explore and interact with other races, though not always successfully! In ancient times, people found their way around using various landmarks and rudimentary maps and this worked well locally, but different methods were needed for travelling further afield across featureless terrain such as deserts or seas. Travellers therefore needed a frame of reference to fix their position. Both the Phoenicians (600 B.C.) and the Polynesians (400 A.D.) used the heavens to calculate latitude. It still took a while, but over the centuries increasingly sophisticated devices were designed to measure the height of the sun and stars above the horizon and thereby measure latitude. The first instruments used at sea to measure latitude were the quadrant and the astrolabe, both of which had been used for years by astronomers to measure the inclination of stars. But knowing latitude wasn’t enough, as to determine an exact location you also needed to measure a line of longitude.

Great minds had tried for centuries to develop a method of determining longitude. Hipparchus, a Greek astronomer (190–120 B.C.), was the first to specify location using latitude and longitude as co-ordinates. He proposed a zero meridian passing through Rhodes. He further suggested that absolute time be determined by observing lunar eclipses, measuring the time when a lunar eclipse started and finished, and finding the difference between this absolute time and local time. But his method required an accurate clock, something which had yet to be invented. Then in 1530 Gemma Frisius proposed a new method of calculating longitude using a clock. This clock would be set on departure and kept at absolute time, which could then be compared with the local time on arrival. Unfortunately, sufficiently accurate clocks weren’t going to be available for another two hundred and thirty years or so, but when they were the method Frisius used was shown to work. Calculating exact longitude was not only important for the safety of navigators, but vital for developing sea-borne trade. So in 1567, Philip II of Spain offered a prize to any person who could provide a solution to the problem. This was followed in 1598 by a similar challenge from Philip III, to whom Galileo wrote, telling him that eclipses of Jupiter’s moons would reveal the secret. The King remained unconvinced. In 1667, the Italian astronomer Cassini was persuaded to visit the Academie Royale des Sciences observatory in Paris and as Galileo had suggested, he used Jupiter’s moons to map the world and the eclipses of Jupiter’s moons were timed in Paris using a pendulum clock. In 1681, Cassini travelled to the island of Goree in the West Indies to repeat his measurements. Absolute time was found on the island by observing the eclipses, and this was compared to local time (obtained using the sun), so enabling the island’s longitude to be calculated. So now, the problem of determining longitude on land had been solved, but the method was useless at sea because a ship’s movements made it impossible to time the eclipses of Jupiter’s moons accurately. As a result, in 1714 the English Parliament offered a prize of £20,000 to anyone who could determine longitude at sea to an accuracy of within half a degree, which is two minutes as the Earth rotates three hundred and sixty degrees every twenty-four hours, therefore every one degree of longitude corresponds to four minutes.

Many eminent scientists set to work, but it was an unknown amateur clockmaker from Yorkshire, John Harrison, who rose to the challenge. He saw time as the key and realised that if you could determine local time (from the position of the sun) and the time at some reference point (like Greenwich), you could calculate the time difference between the two. From this, you could work out how far apart the two places were in terms of longitude. The problem was that back then, no timepiece existed which could be set at home and relied on to keep time accurately whilst at sea, because pendulums were notoriously unreliable due to the ship’s movement. It meant that even if local time could be determined from the noonday sun, there was no time to compare it against and this was the problem that Harrison set out to solve. After decades of diligence and many design changes, Harrison eventually produced his marine chronometer, a spring-driven clock that could measure longitude to within the half-degree required for the £20,000 prize. Despite this, he was initially given just half the promised amount. On a voyage from England to Jamaica in 1761–62, his chronometer lost just five seconds in over two months at sea. It was now possible for a navigator to determine local time by measuring high noon, and compare this to the absolute time, which had been set on an accurate chronometer at the start of the voyage. With this information, he could then determine the number of degrees of longitude that he had traversed during his journey. As a result, both latitude and longitude could now be determined accurately in terms of degrees, minutes and seconds and for the first time it was possible to determine exactly where on Earth you were. As time continued to pass, industrial changes were occurring, the railways came and it was realised that a system of regular timekeeping was needed for timetables. By the mid-1850s, almost all public clocks in Britain were set to Greenwich Mean Time and it finally became Britain’s legal standard time in 1880. Then at noon on November 18, 1883, North American railway systems adopted a standardised system of keeping time that used hour-wide time zones. It took many years, but eventually people around the world began using the same timekeeping system.

Math Clock

Technology was and still is continually moving us forward, so many years later the Global Positioning System, or GPS was invented. The first satellite in the system, Navstar 1, was launched on 22 February 1978 and today it is all done electronically through this world-wide radio navigation system made up of a constellation of 24 satellites and their ground stations. These ‘artificial stars’ are used as reference points to calculate a terrestrial position to within an accuracy of a few metres. Then some years later a man working as a concert organiser was struggling to get equipment and bands to musical event locations on time due to inadequate address information. So it was that in 2013, he and three others founded What3Words and the company was incorporated in March 2013 with a patent application for the core technology filed in April 2013. The What3Words system uses a grid of 3 metre by 3 metre squares covering the whole world, with every square given a unique address composed of three words. As of May 2020, the addresses are available in 43 languages according to the What3Words online map, though the addresses are not translations of the same words. Each language uses a word-list of 25,000 words (40,000 in English, as it covers the sea as well as land). The lists have been manually filtered to take account of word length, distinctiveness, frequency, ease of spelling and pronunciation to reduce the potential for confusion and remove offensive words. The system relies on a fixed algorithm in combination with a limited database and the core technology is contained within a file of about 10MB,rather than a large database of every location on earth. The database also assigns more memorable words to locations in urban areas. According to the company this system also distributes similar-sounding three-word combinations around the world to enable both human and automated error-checking, although these claims have been disputed. The result is that if a three-word combination is entered slightly incorrectly and the result is still a valid What3Words reference, then the location will usually be so far away from the user’s intended area that the error will be immediately obvious to both a user and an intelligent error-checking system. In January 2018, Mercedes-Benz bought approximately ten per cent of the company and announced its support in future versions of the Mercedes-Benz User Experience and navigation system. Their A-Class, launched in May 2018, became the first vehicle in the world with What3Words on board. As a result, through scientific advances over very many years, we now have a way of accurate navigation around the whole world.

SatNav

Actually What3Words has proved to be useful for emergency services in finding people, especially in remote areas. Some also use it when meeting family and friends. It is even possible to convert National Grid References to What3Words addresses. I have personally found the system to be quite useful and more detail on how to use and download the it can be found on their website at: https://what3words.com/how-to-use-the-what3words-app whilst the main website is: what3words.com
You might want to click on the following few examples:
Westward Ho!, North Devon, U.K.: w3w.co/slang.precautions.powder
Taj Mahal, India: w3w.co/forgives.shed.mixes
Opera House, Sydney, Australia: w3w.co/family.handy.crisis
Cathedral Square, Peterborough: w3w.co/actual.called.grain
McDonalds, Leicester: w3w.co/plans.images.gates

To close this week…
Life can be all about consequences. As a youngster I was taught to fish and I would go float fishing in our local river, though I rarely caught anything as I found it difficult to spot when the float moved after a fish had taken the bait. But it passed the time, I was out in the fresh air, it was quiet and relaxing for me. On one occasion though I forgot to empty the plastic box of unused maggots before going home, so a couple of days later I opened the box and a few flies flew! I swiftly dealt with them and after that I always fed the fish with the unused maggots before I headed home. Buying more maggots was far better than upsetting mum…

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