Homage to Eef Willems

17 March 2020

Written by Maarten van Eden: “Greetings from sailing ship the OOSTERSCHELDE. 150 nautical miles west of A Coruña with final destination Rotterdam. About four years ago, I graduated from the Enkhuizer Nautical college. Eef Willems teaches the subject astronomical navigation, a subject feared by many, here. She does that with a drive that anyone would be jealous of, as the English would say, she doesn’t take any prisoners. I, personally, like all the fuss with heights, geographical positions and lines (drawn with pencil!) on the map. So when I go to the sea I take my sextant and nautical tables with me, more for the nostalgia than anything else.

The first reaction I get when I climb on board with the recognizable wooden suitcase is homeric derision. As the traditional practice of astronomical navigation is now so old fashioned that it became astrology again, I hope that a man with his sextant creates a certain mystique. You do need something to differentiate yourself from others.

Our trip from Cape Verde to the Mediterranean, now going to Rotterdam only, turns out to be a gem for the asterisk / planet shooting. Usually, I am satisfied with the occasional afternoon sun and an azimuth, but now, partly because of the beautiful weather day in and day out, the sky is open to us. That is going on? The planet Venus is currently seen at its most distant (elongation) of the sun from earth and is high in the sky  above the sun when the sun goes down. It shines so brightly in all its splendor that it can be seen before the sun goes down. While only a quarter of the planet is illuminated from earth (comparable to the first and last quarter of the moon). This can be seen with a bit of binoculars. This way, you have extensive time to determine the height of Venus. With the advancement of the nautical twilight time, the brightest star in the sky becomes visible: namely Sirius (part of the big dog), next to the later appearing Orion.

Venus in the west and Sirius in the south deliver a beautiful, almost rectangular bearing and thus a razor-sharp fix. Now I hear Eef say yes that all intersecting lines do, where is your third poll? but I have to admit that buggy stuff is a but rusty so I have to deal with it!

Maarten van Eden, the difficult student.

PS: In the morning, in the east Mars, Jupiter and Saturn will be chasing each other, also very nice to see.