ENDURANCE

West Lake Bonney, Taylor Valley, Antarctica
Reporting from East Lake Bonney Basecamp

We continue to struggle with the melt hole. Since we are starting our work here nearly a month earlier than we did last year the ice is both colder and thicker (4 meters thick, compared to 3 meters last year), making melting much trickier. Last year the hole took 3 days to melt out. This year’s hole was started 13 days ago and while the wind shield we put up yesterday has helped significantly, so far the hole is still too small for the bot to fit all the way through. Bart and Kristof have become amateur Hotsy wranglers, coaxing the fussy machinery to work and readjusting the melt coils throughout the course of the day. Our original ice cowboys, Maciej and Jim, take the night shift. Between the four of them we have the Hotsies running 24 hours a day.

Vickie and Bill left the Bot House for a brief trip to set up a GPS base station at the nearest benchmark, located at the Blood Falls Camp, where we were based last year. The base station will remain anchored to the benchmark for the duration of our work here. The GPS system will allow us to obtain real-time, high-precision coordinates for the sonde-drop points that the bot will travel to once we start running missions.

Bill unpacks the base station for our Real Time Kinematic (RTK) GPS system.

Later in the day, the hole finally cleared out enough that we could just barely submerge the bot, without the orange syntactic blocks, to run some basic tests and check that none of the electronics housings were leaking. No leaks turned up and all systems functioned normally, with the exception of some minor problems with a data line to the sonde camera.

Vickie and Kristof watch to make sure the bot will not bump the side of the melt hole as it is lowered into the water for the first time this season.

The bot, minus syntactic blocks just barely fits in the melt hole for some initial in-water testing. Two Hotsy fingers (coils) continue to melt the ice during the tests.

As of this evening, the bottom of the hole is still too narrow, so it will be another long night out on the lake for the Hotsy cowboys. Thanks guys!

Reporting by Vickie Siegel

West Lake Bonney, Taylor Valley, Antarctica
Reporting from East Lake Bonney Basecamp

Halloween at Lake Bonney!

After a filling breakfast of pumpkin pancakes, compliments of Emma, we hopped on the ATVs for the morning commute to the Bot House. To give the Halloween morning a spooky feel, we made a pit stop to look at two of the many frozen, mummified seals on the east lobe of the lake (for more about these guys, see November 29 of last year’s blog).

Upon arriving at the Bot House, Chris, Kristof, Bart and Vickie worked through the pre-dive checklist for the bot in preparation for its first dunk while Bill, Jim, and Maciek went about clearing the layer of ice that had re-frozen over the melt hole. Once this inch-thick skin and the Hotsy melt fingers were removed, it became apparent that the hole was still not quite big enough. The bot has a diameter of just about 7 feet and the hole had a bulge of ice on one side that made it an oval rather than a circle.

Wearing a harness for safety, Jim breaks up the ice that has formed on the surface of the melt hole.

After chipping at the bulge for a minute or two with little success, Jim decided to restart the Hotsy fingers and put them to work melting out the bulge. After a minute or two of watching the water surface re-freeze before our eyes, even as the Hotsies were chugging away, we decided to employ some more advanced strategies. The floor Bot House sits about 1 meter above the surface of the lake ice so the melt hole is fairly exposed to the cold wind gusting up and down the valley. The wind also chills the interior of the House, particularly when we have the moon pool cover (a sturdy plywood panel on rails) open to allow access to the melt hole. What we needed was something to cut the wind so we took some 2.5 x 2.5 m pieces of heavy, coated fabric and fastened it to the perimeter of the moon pool. To anchor the bottom of the fabric, which was now flopping in the wind, Jim crawled under the floor, pulled the excess fabric away from the hole, laid it flat on the ice and covered it with chunks of ice that had been chipped out of the hole.

Bill and Bart attach the windbreak fabric to the edge of the floor’s moon pool.

Jim stacks blocks of ice on the windbreak fabric to anchor it down.

Now that the bot dunk-worthy and the hole has a little more insulation from the elements we just have to let the Hotsies do their thing and return in the morning.

Not having a lot of entertainment options for off-time (nor costumes for Halloween festivities), Chris decided to dress up the team by way of crayon drawing!

Reporting by Vickie Siegel

West Lake Bonney, Taylor Valley, Antarctica
Reporting from East Lake Bonney Basecamp

The “morning” (we now have 24 hour light—just some hours are dimmer than others because the surrounding peaks shadow the valley) brought the clearest blue skies we’ve yet had this year. It was somewhat warmer, only -14C, and the sun shone brightly as we commuted to work. We found the center of West Lake Bonney considerably more empty than yesterday—all of the carps but Mombok had helicoptered out early this morning. Maciek and Jim continued work on the melt hole—it is now an oval approximately 2.5m x 2m. It needs to reach a circle 2.5 m in diameter before we can send the bot down.

The morning was spent cleaning up the bot house and reorganizing following the arrival of a dozen tables from McMurdo along with a telcom team that installed a solar powered internet link to the Bonney Riegel repeater station. Mission Control was set up and projection screens installed for the main vehicle status, situational awareness, and science instrument displays. The last of the sensors were installed on the vehicle and the second battery was loaded. Around 6pm the vehicle was put on charge while Kristof read off a checklist of all electrical connectors for inspection. Several of us went around the vehicle and checked over a hundred connections while Vickie performed the final assembly of the science payload sonde sensor suite.

Bart gives the new batteries a final once-over before closing them up in water-tight housings.

Vickie ties up loose cables on the sonde.

Around mid-day Bill and Maciej drove 400 meters over to the edge of Taylor Glacier to determine a suitable location for an access hole for the vehicle. The idea is complex and will be described in detail later as the mission unfolds, but basically we will drive under the ice to this auxiliary hole and re-ballast the vehicle so that it is capable of exploring under the hypersaline chemocline at 14m depth. The water density shift at that point is so pronounced that the current vehicle would bob like a cork on water at that interface and only an additional 250 kg of ballast will allow it to submerge. We have a permit to take the vehicle beneath the chemocline only at this location. The plan is to then lower the vehicle into the chemocline (using a portable hoist) and release it, at which point it will map the bottom of the lake leading into the glacier. We believe that there is a possibility of a substantial cave under the glacier at the center point of the lake but only an actual exploratory mission will prove this out.

Maciej notes the location where he and Jim will start melting a second hole, about 30 meters from the Taylor Glacier.

With some luck the bot house melt hole will be large enough by tomorrow to perform the traditional “dunk” test to check out vehicle integrity.

Reporting by Vickie Siegel

West Lake Bonney, Taylor Valley, Antarctica
Reporting from East Lake Bonney Basecamp

The past week has been a blur. Bill Stone shipped out to East Lake Bonney main camp on Friday October 22 to guide the assembly of the Bot Garage foundation while the remaining SAS crew continued bot checkout and assembly at the incinerator building at McMurdo. Ten carpenters (“carps”) from McMurdo led by David “Mombok” Story had already flown out to West Lake Bonney the previous day and were camped in an array of small tents on the ice around the melt hole. They had also constructed two “Jamesway” huts (3 x 4 meter half-cylinder habitats made by Weather Haven) and were using those for a mess hall and work shop—environmental regulations do not allow any kind of contaminant to be released in the Dry Valleys so wood sawing has to take place indoors and be vacuumed up. About this time bad weather set in again with strong winds (katabatics) coming down off the Antarctic ice sheet, hitting 30 knots in Taylor Valley, driving wind chill down below -35F. Helo ops stopped for close to two days and the bot did not arrive until Tuesday morning. By that time the overall crew of 15 (in addition to the carps there were Maciej Obryk, Jim Olech, Emma Steger, Loralee Ryan, and Bill Stone) had worked two days to get the lab foundation set out and leveled. Then came the heavy lifting of getting all 16 segments loaded and bolted up, with around 300 connections to be made.

Condition 2 storms grounded most of the team in McMurdo for several days.

Work continues in the Incinerator. Vickie installs a new mount for the Delta T and the bot is plugged into the new batteries (on orange crate, left) for the first time.

Bill and a team of carpenters work to assemble the floor of the Bot House on Lake Bonney while the rest of the team is wrapping up work in McMurdo.

Life in Taylor valley is cold. Each morning we have to commute 20 to 30 minutes by six-wheeled ATV from ELB main camp to the melt hole (the previous year’s camp at Blood Falls is occupied this season by a small team of glaciologists). The coldest it has been, counting wind chill, was -58F. So you have to layer up and cover every square centimeter of exposed skin and wear goggles. Even with all that the ATV driver’s thumb controlling the throttle will get painfully cold unless you place a heater pad inside the thumb of the glove. The fastest route between ELB and the ENDURANCE melt hole is by following the “moat” ice — a rim of smooth ice surrounding the edges of the lake about 5 to 10 meters in width. The rest of the lake is a series of up to 1 meter high wind blown ridges and troughs that make cross-lake traffic tedious, slow, and bumpy even in a six wheeled vehicle. The moat ice is frequently a criss cross of crack patterns (not unlike the moon Europa’s surface), some of which are up to 15 cm wide and demand attention while driving.

Maciej and Jim have spent the past week running up to four “Hotsy” melt systems—complicated and noisy devices that burn “mogas” to heat glycol which runs through a spiral shaped stainless tube that hangs in the water, slowly enlarging the hole through which ENDURANCE must fit to gain access to the sub-ice lake. Each Hotsy also requires a large generator to power its electric pumps to push the hot glycol through the tubes, so at times the cacophony is the only thing you can hear near the melt hole. These two have been putting in a relentless around the clock effort since the heaters require recharging every four hours, day and night. With some luck the hole will be finished tomorrow.

Jim maintains the Hotsy devices that are melting the bot’s hole in the ice.

The morning of October 27 was clear and almost dead calm. Helo ops was back up and delivered the bot with pin point accuracy, landing it on top of the completed platform. A few hours later the remaining six SAS crew (Vickie Siegel, Bart Hogan, Kristof Richmond, Shilpa Gulati, Chris Flesher, Rachel Price) arrived on a Bell 212 at the melt hole. By this time half of the large Weather Haven hemisphere frame was up and in place. By 5pm we had the frame complete and began pulling up the multiple layers of over shell—first an inner layer, then 18 overlapped insulation layers and the final exterior weather layer. Each of these required ropes to be tossed over top of the 8m high arch in order to pull the sheets over and tie them down. By then the wind was picking up again and just managed to get everything tied down before gusts were back in the 15 to 20 knot range coming up the valley.

Our new batteries arrive at West Lake Bonney as an internal helo load.

The next two days (October 28 and 29) were spent finishing off the interior of the bot house (getting heating up and running, getting the electric power installed—a 10 kW diesel generator this year) and beginning the unpacking of ENDURANCE gear. By the evening of October 29th most of the vehicle sensors were installed, the profiler servo motors were in place, and one of the new upgrade batteries was completed and loaded into its waterproof housing.

Scheduled for tomorrow: initial power up of the bot for a full systems and sensor integrity check and scouting the location for the sub-chemocline glacier face access melt hole.

Reporting by Vickie Siegel

Antarctica
Reporting from McMurdo Station

Over the past week we have continued to make preparations for our field work at Lake Bonney. Maciej, Jim, and Loralee flew out to our camp on East Lake Bonney several days ago. They have been preparing camp for the rest of the team and have been melting an 8 foot diameter hole in the ice that will allow us to deploy Endurance in the lake.

Back in McMurdo, Chris, Vickie, and Emma have been joined by other members of the Stone Aerospace team: Bill Stone, Bart Hogan, Kristof Richmond, Shilpa Gulati and Rachel Price. This influx of troops has made The Incinerator a much livelier place. We are currently working to make sure that we deal with any Endurance maintenance, software, or upgrade issues here in McMurdo before the bot is shipped out to the field. A few problems have been encountered but we are steadily working through them and are still on schedule. Thus far we have plugged in all sensors and established that they are working. Chris has been working in the cPCI (the bot’s main computer), swapping out an old hard drive for a bigger one, installing an additional hard drive, and rewiring the cPCI’s connection to bot’s multibeam sonar unit, the Delta T, to allow us to view this sensor’s high-quality sonar data on our mission control monitors in real time.

While inspecting the vehicle, Rachel noticed that one of the six thrusters was leaking vegetable oil. The thrusters are pressure-filled with this biodegradable oil to keep water from leaking in, so it is important that that pressure be maintained. Upon removing the thruster we saw that it is leaking from the cable that runs from the thruster body to the motor electronics pod. We’re not sure why it suddenly began leaking but the most likely answer is that some part of the connector expands and contracts with temperature changes differently than the part it mates to. Since the bot had a nice cold, exposed ride on a trailer down to the warm, sheltered Incinerator, it recently went through some drastic heat changes, which may have caused the leak. Fortunately, we have a spare thruster that we can swap in. We also ordered some replacement oil and parts from the states for the leaky thruster and these arrived today with Shilpa, the final SAS installment to Team Endurance for this year.

Another system we have been working on is the vehicle batteries. The batteries the robot used last season are the same batteries that were used for the DepthX vehicle, are 4 years old, and have seen a lot of action. They are large, custom designed batteries using lithium ion cells and they are rechargeable. However, like any rechargeable battery, they degrade over time and eventually they will become unusable. Anticipating this degradation, Stone Aerospace used some upgrade funding from NASA to design and build two new batteries. We built these new batteries in August and shipped them down to McMurdo soon after. Chris and Bart have been busy finishing various wiring odds and ends on these batteries and soon they should be ready to test on the vehicle. The plan is that we’ll use these new, more powerful batteries for all of the Endurance missions this year and we’ll have the old batteries on standby as back-ups. While the old stacks were charged a few times over the winter by a technician here in McMurdo, they were still in pretty bad shape (very low charge and in a few cases individual cells even had negative charge) when we arrived to retrieve them, thus, we are now working to carefully and slowly bring them back up to full charge, if possible.

Chris checks out the wiring on one of the bot’s new batteries.

We also continue to get up to speed with living and working in Antarctica. All of the new arrivals have gone through their intro briefings. Since Rachel and Emma weren’t here on the Ice with us last year, they had to go through Happy Camper School, where newbies learn cold weather survival skills for 2 days and spend the night camped out in the snow. In the meantime, Vickie and Bill, accompanied by McMurdo’s dive coordination officers, each did a dive under the sea ice in McMurdo Sound. The extremely cold water (about -1.9°C or 28.6°F) means that divers here typically use drysuits, full face masks and surface-supplied air. These check-out dives, in addition to extensive training completed in the states, qualify Vickie and Bill to serve as divers for the Endurance project. As such they will be able smooth any sharp corners around the bottom edge of the ice hole to prevent damage to the bot and to swim a short distance to the bot and attach a tow rope in the event of a minor mishap.

Vickie Siegel enters the icy seawater.

Reporting by Vickie Siegel