Thursday 7 February 2008 à 12:41

Eclipse of the sun!

Par Patrice Pruvost. Correspondent aboard the Umitaka Maru

The good weather has been with us since yesterday. We thoroughly enjoy the magnificent spectacle offered us by the Antarctic continent with its immaculate white ice cap and floating icebergs.

Even though the thermometer reads -6, the sun’s rays provide us with a little warmth, a very nice feeling after all the days of bad weather we have just been through. The weather report from Dumont D'Urville base tells us we will have two days of good weather. Then things may go downhill. Let’s hope that we can continue to work! With this good weather, the stations come one after another in good time. We are moving along well and we are in the period for the sampling program.

Sampling plan for the Umitaka Maru. The stars mark the stations already conducted; the squares, those that are planned.

We carried out several fruitful casts of the trawl nets last night. We collected the species we hoped to. In the zone we are currently sailing in, the species diversity of pelagic fish is less than in the great depths link to dispatch of February 1). Each cast brings up essentially one species. The one we catch most often is Pleuragramma antarcticum, one of the rare pelagic species of the Antarctic coast. We find great quantities of it at several stages of life—larvae, juveniles and adults. We are really delighted by the catches. Our research effort focuses on the study of Pleuragramma antarcticum.

Three o’clock in the morning, here a synonym for sunrise and the end of the shift, © P. Koubbi.

After each cast, we sort, count and condition the different specimens. These operations are long. Moreover, spotting the many little larvae of teleost fish in the middle of the plankton is a difficult undertaking. We finish treating the samples at 3h in the morning. We have just enough time to catch a little sleep; the next station starts at 6h30. We know that, in these shallow depths, the operations come one after another quickly and we are going to spend a good amount of time working in the laboratory, whatever the hour may be. During the day, we use the breaks between equipment changes or between stations either for resting or for quick debriefings before we eat.

Quick convivial debriefing in Philippe’s cabin! © P. Koubbi.

In the early afternoon, we are lucky to be able to admire a partial eclipse of the sun.

Partial eclipse of the sun.

For a few minutes, the moon passes between the Earth and the sun. We use a sextant to watch the phenomenon. This navigational instrument, which is used to calculate the height of a heavenly body (star or sun) above the horizon, is equipped with protective lenses.

Patrice watches the partial eclipse of the sun using the sextant.

From the angle measured by the sextant and the time, we can figure out our position in latitude and longitude using tables and a series of calculations. Even if the instrument is used less and less since the arrival of satellite navigation, sailors continue to learn how to use it. It has the enormous benefit of never breaking down! One can never be too careful about electronics at sea!



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