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There was breathing room for the science crew to compete in the shipboard Ping-Pong tournament, do some equatorial sunbathing on a popular upper deck, take a dip in a makeshift pool near the stern, watch a video in the lounge, use a lower deck exercise room, read a book from the library or vie to win the men's collegiate basketball tournament pool.
"Go Duke Blue Devils!!!!" read one Duke Blue-tinted screen saver message that mysteriously appeared on two video monitors last Friday in the DSL 120 side scan sonar control van.
By the Saturday midnight shift, that message was replaced by a more pointed: "We all need to realize the truth. Duke is UNSTOPPABLE!!!"
While still participating in spare-moment diversions, the researchers' pace threatened to become overwhelming - and adequate sleep a rare commodity - after the DSL 120 was pulled back to the surface before dawn Saturday morning.
By 2 p.m., RV Atlantis's crew was preparing to launch the more demanding Argo II, whose six on-board cameras could potentially swamp the researchers with visual overload, leaving Duke basketball boasts no opportunity to pop on unattended viewing screens.
After the DSL 120 control van was reconfigured to become the Argo II nerve center, researchers would spend long hours there monitoring all those incoming still and moving video pictures for interesting features.
They would note their observations in a computerized "event logging" program organized by Duke first year graduate student Carrie Lee. They would write other impressions in a logbook. And they would record incoming images, and separate navigational information as well, on six different sets of electronic video or data tapes.
At the first research meeting since the DSL 120's launching on Tuesday, March 16, Hess Deep chief scientist Jeff Karson of Duke said the control van would become "more crowded and definitely more hectic" after it became operations hub for the
Argo II.
During the comparatively relaxed DSL 120 side-scan sonar runs, all science watch members except for the shift leaders could get away with just four hours of van duty a day without jeopardizing the more limited data collection.
There will be so much more to do during Argo II that mandatory watch hours will be doubled.
The just-ended side-scan sonar survey used sound waves to paint shadowy impressions of some of the geology along a 21-mile long stretch of Hess Deep's north cliff face.
As Atlantis towed the DSL 120 along three predetermined course tracks at a sedate rate of less than 1 knot, those wispy side scan sonar images, providing only overall hints and impressions, rolled out slowly on control van monitors and on paper printouts.
The electronic sonar images were also stored on tape for processing that will make them clearer and easier to read. Meanwhile, rolls of the DSL 120 paper printouts, a center of scientific attention back in the control van, have now been spread out on a table in Atlantis's main science lab.
Printout frames showing prominent structures or strong sonar reflections have been singled out there by affixing them with yellow office post-it stickers. These frames are now being used as guides for where to send Argo II.
Argo's role will be more dramatic. Its camera array will provide sharp, detailed pictures of the study area's most geologically interesting locations. In the minds of Karson and other Hess Deep expedition scientists, "interesting" means containing information that helps explain more about how new crust is created along mid-ocean ridges like the nearby East Pacific Rise.
Argo's images will also be "mosaicked" - meaning electronically pasted together with special computer programs - to make Hess Deep photo montages at a larger scale than has ever been attempted before.
Those records will not only provide spectacular vistas of the "best of Hess Deep." They will also help scientists pinpoint where to dive when the manned research submarine Alvin begins operations about March 25.
The intensified Argo II schedule means individual scientist's and student's time in the control van will now total eight hours a day, with those on the midnight to four a.m. watch, for example, all returning between noon and 4 p.m.
There will also be expanded responsibilities for the Woods Hole Oceanographic Institution crews that control both kinds of unmanned, cable-tethered scientific probes.
Maneuvering the side scan sonar meant switching on its tow cable winch to make it "fly" higher or lower, or asking
Atlantis's bridge to adjust the ship's speed and heading so that the "fish" could be towed in new directions.
Argo II is also attached to a cable that, like DSL 120, acts as an electronic communications link as well. But Argo is more like a high tech marionette than a towed vehicle. Since it will operate within yards of the rock face, and moves at a crawling pace of only about one foot per second, it is not so much maneuvered as it is nudged.
So Argo II's pilots must do much more than operate a winch. They must also use hand controls to remotely activate on-board "thrusters" that turn Argo II from side to side some two miles below the ship. And the pilots must choreograph what they do with Argo II's navigators, who, operating from within the van, use a computer-assisted link to adjust the ship's own position as needed.
When it is in this computer-controlled state, called "dynamic positioning," Atlantis uses thrusters of its own to aid the maneuvering. Its two rear propellers, plus a jet-type thruster, can be pointed in any direction, allowing Atlantis to hover in one spot or move very slowly but precisely.
Up on Atlantis's bridge, experienced crew members like Third Mate Rick Bean will keep their eyes on a computer screen that compares the ship's actual location with the computer-targeted location. During dynamic positioning, "the only thing we are doing is making sure the ship is moving where it's told to go," Bean said.
It was shortly before 2:30 p.m. on Saturday when Argo II, an equipment-crammed 15-foot-long tubular frame shaped like a long box, was lifted from the same part of Atlantis's deck as DSL 120 had been. Lowered over the edge, it immediately sank like a stone into the clear Pacific water, its cable dropping behind it.
The noon-to-4 p.m. scientific watch members, who had been busy photographing the event from an upper deck, immediately assembled in the control van where monitors displayed floodlit images from two of Argo II's cameras as the vehicle began its two-hour-long descent into the abyss.
At this point there was nothing to look at but water. So the team went over its duties: the screens to constantly monitor, the tapes to change every two or four hours, and the navigational charts that would have to be updated every five minutes.
Everyone should know how to do everything, watch leader Jay Miller of Texas A&M University stressed. Because doing any one task could quickly become taxing, plans were to rotate from one responsibility to another frequently There would be enough to do that some wondered if it would indeed be possible to do it all.
When the same watch returned at midnight, the start of Sunday, March 21, the video screens were now displaying organized stacks of rocks assembled in parallel rows that pointed up the cliff face at the same off-vertical angles.
"That's a sheeted dike complex," said an excited Karson, "one of the main things we came out to look for in the first place. So the first place we came down to in the Argo is a nice, interesting area.
"Everything is going very well."
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