Friday 28 December 2007 à 12:12

Moon games!

Par Sophie Mouge. Correspondent aboard the Aurora Australis

The day begins with the magnificent sight of the moon around three o’clock in the morning. One more amazing spectacle!

The orb looks a bit deformed, because of the complex phenomena of light refraction in the dense atmosphere.

Moon at 3 h in the morning.

Another view, the mood at the same early hour.

Four days ago the moon was full. It’s beginning to wane now. If we look closely at the photo, we can see that the part of the moon that is no longer lit by the sun is on the left. In the northern hemisphere, this would correspond to the end of the First Quarter but in the southern hemisphere, it’s the beginning of the Last Quarter! People who live in the northern hemisphere see the moon inverted compared to the view in the southern hemisphere. Here down under, people imagine they see a seal’s head or a rabbit’s in the moon’s surface.

During this time, Marc and Fred are entering data in the database created by the Museum. They are recording all the information about the specimens that have been caught, such as the specimen’s record number, the number of species collected, whether a tissue sample was taken, specifics of conservation, etc.

Marc Eleaume and Frédéric Busson are entering data in the database.

It is Friday, December 28, but few of us still think of the date. Instead, the days move to the rhythm of fishing equipment being hauled in!

A lot of us have been skipping breakfast to catch a little more sleep. In the morning, the day shift, composed of Bertrand, Romain, Thomas and Samuel, wake up and relieve the night shift, who are still busy packing up the organisms collected in the last trawl.

Shortly after, a new trawl, identified as the 132nd oceanographic event since the mission began, lands on the deck of the Aurora Australis. This one dragged the bottom at a depth of about 600 meters. It reveals a seafloor rich in glass sponges: two big white sponges, shaped like chimneys, about 15 kg each, are pulled from the net intact. The biologists and crew members as well come to take photos of these superb specimens, whose white color recalls that of the iceberg floating behind the ship.

Two 70-cm glass sponges collected at 600 meters depth.

At 16h30, everybody is very focused. The trawl is stuck, hooked on something 400 meters down. One of the chains that fasten it to the ship’s warp is caught on a rock. The technicians realize quickly what’s happened because the traction exerted by the towing line rises sharply and the ship simultaneously loses speed. Immediately, the ship is slowed down. A new maneuver begins. The line is hauled in while the engines are reversed. Once the ship is positioned over the equipment, getting it free is easy. When it arrives on the surface, we can tell, to our great relief, that it is undamaged. The lab people are a little disappointed because the net is nearly empty of specimens.

The sea floor where we are prospecting is very rough. As a result, it is impossible to deploy the trawls for the next few hours. The risk of damaging them is too great. In contrast, the underwater camera is being towed through the water and it records a rich seafloor :

Adelie bank at 145 m deep.

Video commentary: The seafloor being observed shows a continuous tapestry of sessile organisms, dominated by colonial ascidians (sea squirts) and bryozoans. A few big white sponges are dispersed here and there. This shows that the milieu is fairly stable, so this area has not been scrubbed by floating icebergs. All these organisms feed by filtration: they capture particles suspended in the water. Teleost vertebrates cross the field of vision: they are from the genus Trematomus.

Trematomus eulepidotus: caught during a previous trawl at 450 m.

Outside, the weather is still smiling on us. Ashleigh enjoys it, sitting in the sun and drinking a tisane on the wheelhouse deck.

Ashleigh relaxes on the wheelhouse deck.

Sunglasses are absolutely necessary. We are now in the middle of summer in the southern hemisphere and the sun reaches a very high position in the sky every day. Consequently the sun’s rays strike at a sharper angle of incidence than in winter. Moreover, we are located under the ozone hole and receive even more ultraviolet rays (UV). For these two reasons, we have to wear sunglasses and sunscreen whenever we work outside.

Deserted ship with the Antarctic continent in.



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Water temperature: - 0,3 °C Air temperature: - 0,6 °C



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