Saturday, August 13, 2011

Day Three: Bowditch, On Watch

We're all adjusting to our watch schedules, 4 hours at a time, every twelve hours.  Beyond the array of computer screens that we monitor, we have a new assignment: reading chapters from the Bowditch manual on navigation--in preparation for our celestial navigation class to come (compliments of the Chief Mate) and the possibility (hopefully never realized) of navigating lifeboats and/or passing through a tropical cyclone.  It's definitely great to learn more about all things nautical; we are apparently to be tested--theoretical or practical, TBD.

Last night's watch was rather exciting, as we decided to launch an XBT (Expendable Bathythermograph), in order to determine the thermocline (change in temperature with depth) of the surrounding waters.  It starts off with anticipation--there's a cartridge loaded onto a XBT-gun.  Novices are warned of the recoil and the sound.  When launched, however, it falls gently into the ocean, with little flare.  As it falls at 6 knots, the XBT provides a profile of the temperature, which is key in determining the speed of sound, which then informs the seafloor depth given by Multibeam and CHIRP.

Speaking of watches, some of us helped sight and photograph a rare bird, identified by our resident bird-watching expert.  It is a Socoro Mockingbird, likely blown off its little island by a hurricane, and finding refuge on the Melville Deck.  We do hope he sights land, and finds his way there.



--Jasmeet









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