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. NeMO Net RAS System A
 
  System A image, click for full size
System A at Virgin vent. The tripod (left) houses the fluid collector intake and temperature probe A1. Fluid sampler bottles are visible (right) under the yellow flotation spheres. (click for full-size)
 
  image of tripod in its side
Tripod found lying on its side a week after the intial deployment after temperature data suddenly dropped. It was put upright and stablized. Temperature probe A2 visible in the foreground.
 

The NeMO Net RAS System A is located at Virgin, a high-temperature vent in the ASHES vent field. The fluid collector for this system utilizes a tripod which sets directly over the vent, to prevent the intake from becoming clogged with hydrothermal minerals. Hot vent fluid rises and accumulates under the funnel-shaped collector at the top of the tripod where the fluid intake for the sampler and temperate probe A1 is located. The second temperature probe was intended to be placed directly into the hot fluid in the anhydrite mound, but was damaged during deployment and could only be placed next to the vent orifice. Consequently, probe A2 is measuring temperatures near ambient just at the edge of a high-temperature orifice..

A few days after System A was deployed, the data received on shore showed a dramatic temperature drop in probe A1 (see the 'All data' graph below). Scientists still at sea but now surveying Explorer Ridge guessed the tripod must have fallen over. At the end of the Explorer Ridge operations, the ship returned briefly to ASHES and indeed found the tripod on its side. The tripod was righted and then retro-fitted with a "weight belt" around the legs to keep it upright and stable.

For more information use the following links to NeMO Explorer:
Hydrothermal vents
Anhydrite chimneys
ASHES virtual reality site
Video clip of Virgin vent
NeMO at Axial Volcano

Temperature Data from System A
 
. Other images of RAS System A
 
  image of tripod placement   ROPOS positions the titanium fluid collector over the Virgin high temperature vent. Shimmering water rises up and collects in the inverted funnel, where the RAS intake is located. The fluid is pumped through titanium and teflon tubing back to the sampler. This tripod tripod was designed to prevent the precipitation of anhydrite in the RAS fluid intake.  
         
  side-view image of RAS   RAS sampler on the bottom. The acoustic modem transducer is visible on the top, left of center. The 3 vertical white cylinders are pH buffers and acid sensors. The three horzontal cylinders contain the electronics and battery power.  
         
 

distant view of RAS tripod

  View of the titanium tripod over Virgin vent after the first deployment.  
     
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