Science Report:
Today on the ship many of the scientists are trying to do an extra job in addition to the busy schedule we usually maintain. We have scheduled time tomorrow to replace the moorings that we recovered early in the cruise (it seems like a long time ago to us, but it has only been nine days since the recoveries!). So not only must they continue the hectic pace of data collection and analysis, but several instruments must be prepared for their long stay at the bottom of the ocean. Some of these instruments you have already read about.

Sharon Walker is preparing the MAPRs (or Miniature Autonomous Plume Recorders) that will monitor the temperature and concentration of hydrothermal particles in the plumes every hour for the next year. Geoff Lebon is readying a submersible pump to take samples of the particles on the same kind of filters he's been using during the cruise. The pump and electronics are in a stainless steel cage as tall as a man. Every two weeks a computer in a pressure case turns on the pump and sucks water through a filter, separating the tiny suspended particles from seawater. Once a sample is collected a new filter rotates into place above the pump and is ready for the next sample. These samples will be used to examine changes in the kinds of minerals produced by the hydrothermal venting on the seafloor.

Joe Resing will deploy two "osmosamplers" on the moorings. These instruments use a unique system that eliminates the need for battery power. They use osmotic pressure to slowly and continuously draw seawater into a tiny tube. The samplers have two chambers separated by a permeable membrane, one with a dense salt solution and one with fresh water. As the fresh water slowly forces its way into the salt solution to equalize the pressure between the two chambers, it acts as a pump that also draws the outside seawater into the sampling tube. By next year, the almost 100 m long tube will be full of seawater, ready to be cut into pieces and analyzed to give a time series record of changes in the local water chemistry.

Someday instruments may be so sophisticated that scientists will no longer have to go to sea themselves--but that's a long time away!