Archive of September 16th, 2007

	Red star indicates location of R/V Kilo Moana. Click on images for full sized versions.

Teacher at Sea log for Sunday September 16, 2007

Today the science team is happy and working hard. Each watch team of four scientists has a four-hour shift in the Jason Control Van, twice a day. The teams work night and day; there's no need for sunlight because the ocean floor is always pitch black. Instead of sunlight, the Jason 2 and the Medea have a bunch of lights on them to light the way. The Control Van is also very dark, so the scientist can see the computer screens displaying vital information; the door even has a curtain in front of it so that the van remains as dark as possible. The screens display navigation information and what Jason 2's cameras are recording. There is also a camera on the cable and the spool so the Jason crew can monitor the cable length and the tension.

The screens that mesmerize me are the three that show the ocean floor. Last week we mapped this area for backscatter data and found the locations with the "hardest" texture (which is how we interpret high amplitude backscatter). We are exploring those places for rock outcrops where we might collect a sample. Most of the ocean floor is covered by small particle sediment, and the hard rocks we want are usually buried except at outcrops. When we find rocks that are sticking up from the sediment, they are often well attached to the floor and are difficult to pry loose. The Jason 2 has two different types of claws and we can control them very well from the van to get samples free. Once a rock is recovered we photograph it from all sides while it is still in the claw, and then it gets dropped into a milk crate on the Jason 2 so it can be brought to the surface. The milk crates have various sized spaces with aluminum dividers, and the crates are marked with colored tape so that we can remember exactly where each rock was collected.

Listening to the team as it works, I remember when I was a child and I heard NASA scientists describing the various places they would like to collect moon rocks. They knew they had to make their visit as worthwhile as possible. This team has to choose between moving very slowly (about 1 knot) along the bottom while seeing every inch looking for something to sample, or taking 5 hours to pull Jason 2 in and travel at 10 knots to the next study site. The last 48 hours we have been traveling with Jason 2 in the water, so we haven't traveled far. Last night when I went out to watch the stars I looked over the side of the ship and saw waves and bubbles from the various propellers on the Kilo Moana going at different times to keep us in a steady position over Jason 2.

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Presented by the School of Ocean and Earth Science and Technology at the University of Hawaii, with financial support from the National Science Foundation.