December 22, 2008

Today we continued our glacier exploration, this time doing a combination sonde drop and glacier-mapping run in the southernmost area of the glacier face. The mission plan took us first to the delta south of the glacier face where we did a few bonus sonde drops in the shallow waters there. Mission control had to do a little bit of maneuvering to avoid some underwater moraines.

From the southern delta, the bot traveled north along the glacier, scanning it with the DeltaT sonar. Things went smoothly until Leah reported that the fiber was feeding out, not in, meaning that the bot was snagged. We managed to unsnag by diving the bot down and then moving to the side to get out of the snag zone before continuing. As the bot proceeded to head home after that it snagged again and this time the diving trick didn't work. Instead, mission control directed the bot to back up past where, calculated from the distance markings on the fiber, they estimated the snag to be. After backing up, we tried diving again and managed to free the bot. Even with the extra time and battery power this delay consumed, the bot returned home after the six and a half hour mission. Now we have some great 3D data from the southern edge of the glacier face. Our job over the next few days will be to continue scanning the north end of the face.