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Good sailing in fair winds to South Africa

Sunrise met Europa rejoicing on a great sailing morning in fair conditions under all her canvas. ESE winds blowing 16 to 18kn pull her at a good 6 to 7kn in a good NNE-ly course.

Ups and downs in the wind Force and the often passing squalls made for a day where hands were called on deck frequently for sail handling.

First the winds picking up to 25kn made for stowing away the Royal Staysails while easing the Spanker sheets as well, taking a bit of pressure from the aft of the ship and easing the steering. Royals are also set and doused a couple of times when we are hit by showers.

Veering wind in the evening to more Southerly help the steering to come up a bit and set a course in a more Easterly direction.
Unfortunately, following this course, the wind died down in the late evening to less than 5kn also adding a light current against us. Better to get off the area clewing-up all the Squares, some of the Staysails too and start the engines for a while, until the wind picks up during the night.

Further North the diagrams show strong currents that would be against our planned itinerary towards Cape Town, and we don’t want to fall into this area that would affect considerably our speed and progress.

Like that, Europa follows a route that keeps adjusting to the wind forecasts and the follow up on oceanographic currents diagrams. Modern interpretations of those currents and the interactions between them depicted as colored patterns in the world’s oceans assigning a convention of colors to their different speeds and/or temperatures, offer drawings and Nature designs that seem to wrestle the gap between science and art.

Science and art sometimes can touch one another, like two pieces of the jigsaw puzzle which is our human life, and that contact may be made across the borderline between the two respective domains. - M. C. Escher

Inspired by Nature, its doings, and details, the Dutch artist M.C. Escher mastered the marriage between maths and art, featuring mathematical ideas and operations including impossible objects, explorations of infinity, reflection, symmetry, perspective, truncated and stellated polyhedra, hyperbolic geometry, and tessellations.

In our case, local currents are interpreted as a game of colors and shapes, elegant graphics that in the end relate to global planetary processes, climate zones, weather, growth, movements, and migrations of organisms. Here this colorful interpretation tells about upwellings along the Western African coast, allowing the growth of sea life, they indicate the transfers of salt and heat from the warmer southern Indian Ocean to the colder South Atlantic. A process that in the end affects the rates of evaporation in the South Atlantic, so helping the development of weather systems there. Trapped water in Eddies can join the global scale of oceanographic currents that control the planetary climate.

Another piece of art meeting the mathematic sciences is the navigation instrument that we used again today when the sun was visible in the partially cloudy skies: the sextant. After gathering all the information we could during the celestial navigation informative talks we are having during the last days, the Sextants made their way back on deck once more. A reflecting device that, through the use of mirrors, angle scales, shapes, and materials, allows the evaluation of angular measurements between a celestial body (like the sun) and the horizon.

Using these measurements it is possible to locate one’s position on the planet. The principles of such a powerful yet so beautifully crafted device were already established by Isaac Newton. Concepts that started to be implemented around the year 1730, culminating with the first built sextants in 1759 by John Bird, a prototype of the ones still in use nowadays. Putting to work these beautiful works of art and mathematics, today the idea was to take a Meridian passage sight. When the sun crosses the meridian you are sailing on, it will reach its highest point and will be equally far away from sunrise and sunset. This moment is also called Meridian Passage (MP).

At this moment, its true bearing will be 000° or 180°, depending on if you are North or South of the sun, and using a couple of simple formulas latitude can be easily calculated.

Written by:
Jordi Plana Morales | Expedition Guide | Bark EUROPA



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margriet  |  06-04-2022 12:06 uur

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