The natural Navigation: The Right Course, Naturally

A Lancaster uses the moon to navigate at Goodwood Revival last weekend. Maybe not, but nice shot by Ben Davis.

My youngest son has added the word ‘moon’ to his vocabulary of about 7 words. It came as a bit of a surprise as I was in the kitchen early this morning when this strange sound, ‘za mooon’, kept coming out of his mouth. He took my hand, led me to the back door and then pointed up at the object in this photo, neatly solving the mystery of what ‘za mooon’ could possibly mean. Does this mean I might be bringing my work home with me too much?

Time and navigation have a cosy relationship, as John Harrison, inventor of the chronometer that cracked the longitude problem in the 18th Century would attest. The sun, earth, moon and planets and stars have at times been seen as cogs in a huge clock.

So many natural phenomena take their orders from these bodies and tide is one of the best known of these. I took this photo of the tide running past a cardinal off Jersey this weekend. The cardinal is an easterly one, signalling that the safer water lay to the east of it. But could it tell us anything else? With two pieces of information, time and tide table, we can discern others such as the speed of the water and its direction. If we had no other references: no sight of land, no chart, no compass, no GPS… that small patch of water could reveal…

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Last night was one of those occasions where the moon was the natural navigator’s best option. At about 10pm the sky overhead was overcast with broken clouds down to nearer the horizon. The western glow of dusk was gone and the only objects that could be seen were Jupiter and the three-quarter Moon. The cloud meant no Polaris, and the bright moon in the only patch of open sky blotted out the other stars. The Moon plays hard to get at first but on nights like this it can be a very good friend.

Early this evening Mrs G and I escaped for a quick wander aboard Golden Eye, my Contessa 32, in Chichester Harbour. One of the lovely things about the harbour is that when time is short or wind is in short supply it is possible to enjoy a potter on the water that is more akin to a gentle river cruise than a sail.

The 20hp diesel pushed us gently west into a low sun. A moon that was a day off first quarter hung to our left and the line down its midriff, the line between light and dark, pointed neatly down to south on the horizon. There was a gentle breeze. It was forecasted to be from the south-west and obliged by making its way dutifully towards us over the harbour water from between the sun and the moon.