by Kristof Richmond

Well, we haven't been updating much since Justin and Peter (and his beautiful photography equipment) left. We are working hard with reduced personnel. It is hard to believe, but I am leaving in two days as well. In the meantime, I thought I'd share some cell-phone snapshots of the activities around here.

We did have a bit of a break over the weekend, when McMurdo takes two days off (instead of the standard one day per week) to celebrate Thanksgiving. We have been working almost non-stop for several weeks in a row, and decided it was time for the team to relax for a day as well.

We all showed up in the evening to the town Thanksgiving feast. Most people here are far from family, and really go all out to make the celebration special. The galley went all out to make the day happen, even flying in fresh strawberries for dessert.

​Early the next day, a few of us headed out to the observation tube (see Peter's earlier post) just outside town and crawled down to take in the serenity and beauty of the ice underside that ARTEMIS experiences every time its out.

Our time on the ice is short, and we are pushing to get as many missions as possible in before the beautiful weather makes moving equipment on the ice unsafe. The team will be working hard for the remaining time here.

The environment beneath the ice in McMurdo Sound is other-worldly. Literally. That's part of the reason we are studying it - because it provides one of the best terrestrial analogs to what things might be like on Europa. ARTEMIS has 3 active cameras on board, and has been busy capturing scenes of the world below during our missions. Some of these scenes are incredibly beautiful - I can now understand why Antarctic divers reverently call going beneath the ice "entering The Cathedral".  

ARTEMIS flies under a school of fish while gazing up at the ice ceiling. It's amazing how the world below the ice can be so alien, and yet so the same - the fish look like birds underneath a bank of clouds. 

ARTEMIS approaches a sizable jellyfish which swam past our borehole. 

Yesterday was an emotional day as Justin and I departed Antarctica, leaving the rest of the SIMPLE field team to finish out the season.  We're hitting full stride with ARTEMIS now, but there are several key challenges still standing between the team and the data we'd like to collect before the end of the season - a tough time to walk away.

From the States, I'll be starting to write up our results for submission to the academic literature.  I'll also be catching up on a few blog posts I wasn't able to make from the field and reading along whenever Evan and Kristof are able to post from the front lines.

We sat on the C-17 with our new glaciochemist friends from Michigan (check out their field work here).  Generally, the homeward bound on board were exhausted, but satisfied and excited to see family.  At cruising altitude, folks got up and wandered around the aircraft, peering out the windows and stretching out to nap in the mostly empty cargo area.  At the beginning of the flight, we watched the sea ice give way to open ocean.  Just before landing in New Zealand, we watched the sun set for the first time in weeks.

My scheduled time in the field has come to an end.  However, high winds over the past several days have prevented incoming and outgoing C-17 flights, delaying my departure and allowing me a bonus ARTEMIS dive.  I made an effort to get a few more photos of the bot house scene during that dive.

I used some of my bonus time in Antarctica to implement live plotting of ARTEMIS's estimated position and heading in Google Earth.  Mark set it up to be accessible to any computer on the bot house network.  A wall projection of the display improves the team's situational awareness while ARTEMIS moves through various mission stages.

Winds out on the sea ice have been fierce this week.  The view back to McMurdo is often obscured, and we haven't glimpsed Mt. Erebus in days.  Huge snow drifts are piling up all around our camp structures, and the vigorous flapping of the bot house constantly accompanies the sounds of our operations.

Yesterday began with a group photo in the bot house.  I'll have to superimpose John to get the entire field team, but this photo includes the entire group currently at McMurdo.

We are getting more and more capable with ARTEMIS, and we're starting to do some serious science.  Yesterday's dive featured a sampling transect in which ARTEMIS collected water samples and in-situ data at 7 stations distributed over 1.5 km spanning the ice shelf transition.  The 3 km round-trip distance is a new record for ARTEMIS, and the science data set is the richest we've gathered yet.  Brian was able to localize ARTEMIS with strong signal at all stations - through shelf and sea ice.  The dive ended with a huge milestone for the programming team as ARTEMIS performed the first autonomous visual docking to the lighted docking bar under ice.

After the robot was safely docked, we pulled off another big first by extending the ARTEMIS science tower.  Moving parts can be trouble, but the test went very well.  Bill dove to observe the actuation test, and I ran over to the dive hut to snap a few pictures as he came back to the surface:

As always, Antarctica was looking good from SIMPLE camp.

Progress is happening at a terrific rate in SIMPLE camp.  We've been working very long days advancing our science and engineering goals.  Other than a few ours of planning discussions, we've taken today off, with most folks opting to sleep for many hours, as we had ARTEMIS in the water until 4 am last night.

The endless sunshine and super-long work hours are distorting our senses of time, but we remain ever conscious of the impending end of our field season.  Happily, on our past few dives, we've achieved a number of exciting in-water milestones:

• Spooled optical data fiber from the 15km spool on ARTEMIS, and up through a depressor hanging beneath the bot house.
• Created a sonar map of the multi-year sea ice and ice shelf transitions near camp.
• Demonstrated our most basic loss-of-communications autonomous recovery behavior.
• Collected water samples under sea ice and returned them to the bot house.

​Here are some photos from those dives:

Yesterday was a huge day for wildlife sightings.  Those who stayed overnight at camp were surprised to find that a Weddell Seal had wandered into camp the night before.  The seal was bloodied a bit from fighting (this is common), and rested near our camp for about a day and a half before moving on this evening.  Evan, Justin, Vickie, and Brian followed the seal's trail yesterday morning hoping to find the open crack it had come from, but gave up after a half-mile journey in order to start work for the day. 

Keith and I arrived at camp by snowmobile later in the morning and enjoyed the chance to snap a few photos ourselves.  It's important (and required by the Antarctic Treaty!) to keep enough distance not to disturb these animals, so I was happy to have a big lens with me.

Heading back to McMurdo after a long day at camp, we encountered a single Adélie Penguin crossing the "road."  This was an unlikely sighting so far from open water, and the first penguin ever seen by several members of our team.  We spent a few minutes taking pictures, gave a wide berth, and headed home delighted.

We made some great strides with ARTEMIS yesterday.  Buoyancy trim is still not perfect (ARTEMIS has a slight lean to starboard), but after Saturday's adjustments, the vehicle was sitting level enough yesterday that we were able to perform a 10 hour dive with some exciting results.  We:

• drove ARTEMIS around under the sea ice near our camp
• tuned autonomous control loops and tested our new buoyancy-compensating feedforward control
• tested scripting of autonomous motions
• localized ARTEMIS from the surface using the magnetic tracking system
• displayed live science telemetry in the bot house
• docked ARTEMIS to the lighted docking bar under joystick control
• recovered ARTEMIS to the surface using the docking bar rigging​

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Here are some photos of the surface tracking operations led by Brian.  Brian was pleased with the tracking system performance through the ice, and was able to localize ARTEMIS even at 35 m water depth.  In these pictures, try to imagine 7 m of sea ice and brash ice underneath the feet of the tracking team, with ARTEMIS at 35 m water depth, and the bottom of the Ross Sea 700 m below.

The docking bar test was very exciting.  I was "at the wheel" driving ARTEMIS onto the bar.  The system worked very well, and now we've got our first set of images of the docking bar under ice as seen by the actual ARTEMIS cameras.  Evan is using these images to validate our automated visual docking system.  The first fully-automated docking run will be a real milestone for our project, and we feel it getting very close.  Here are some views from the ARTEMIS camera of the docking bar during our piloted approach and docking run.

Since the docking bar hangs straight down through the culvert (and is covered in super-bright LEDs), we can see ARTEMIS attached to it from the surface.

With so many exciting steps taken, group morale was very high at the end of yesterday's dive.  However, we are now feeling serious schedule pressure.  As the austral summer advances, the sea ice beneath our camp will break up and blow out to sea.  We have ambitious goals and only a few precious weeks remaining here on the ice.

We had our third ARTEMIS dive last night and made excellent progress on ballasting.  We had to make a few changes to the ARTEMIS configuration between our last tests in Texas and our first dives here in McMurdo Sound.  As a result, we've had to adjust the number and locations of ballast weights in ARTEMIS to get it to sit level in the water.  Bill dove beneath the ice to make some ballast adjustments last night.  We hope to complete ballasting with some adjustments in the bot house today.

Here's a quick collection of clips form the GoPro we attached to Bill's dive helmet last night.

I went with Keith, Brian, and Justin to the McMurdo Sound observation tube today.  Set up by the USAP a few hundred feet offshore, the observation tube is shaped like a large thermometer, with a roughly 25 foot descent through a pipe into a small bulb with windows.  The pipe runs down through the sea ice, and the bulb windows provide a view into the water all around.  The view is spectacular, but we all throught the sounds of the underwater environment were the highlight of the excursion.  The high-pitched sounds of distant seals can be heard faintly in the tube.

It seems the life-on-other-worlds motivation for our project has settled into the subconscious of McMurdo.  The word "stargate" has come up independently in multiple disparate contexts relating to our field work.  In a field safety meeting, we described the flagged access route from our camp up onto the ice shelf as a "stargate".  Now, completely independently, the USAP carpenters have installed a really nice new stair access to the bot house, and called it STARGATE - the Sea-Ice To Artemis Robot Garage Advanced Terrestrial Entry.  These stairs, their name, and their abundant labeling are all totally fantastic.

Meanwhile, the bot house drill hole took on a particularly "stargate" appearance last night as we lowered ARTEMIS (with its headlight on) out of the culvert and into the open ocean for the first time.  We used the ARTEMIS thrusters to maneuver around the area beneath the culvert (still in a vertical orientation), and confirmed the result of our ballasting efforts based on the scale readings from the night before.

Yesterday (Monday), we submerged ARTEMIS in the Ross Sea for the first time.  This is a huge milestone for us, but also one that we hope will feel insignificant soon as we progress to more ambitious operations.

The day started with priming of the pumped water instruments and sampling lines.  These need to be filled with seawater (and emptied of air) before ARTEMIS can go in the water for buoyancy adjustment.  The science team used a Niskin Bottle sampler to bring up seawater from beneath the culvert for this purpose.  Meanwhile, the software and mechanical teams prepared the vehicle for submersion.

The actual dunking process was slow as we were very careful about mechanical interference between the robot and the culvert.  We were able to fully submerge ARTEMIS and record its weight in water using a calibrated dial spring scale from Crary lab supply.  This was the first step in the critical process of ballasting ARTEMIS to sit at near neutral buoyancy in the water of the Ross Sea.

From McMurdo and from our field site, the sun crosses over Mt. Discovery (or behind just two weeks ago!) at about midnight.  The weather was a little nasty yesterday, but easing as we finally left the field site a little after 11 pm.  The low sun and easing weather provided an epic view to the South as we headed home for the night.

Britney gave the third of three talks by our project in the Sunday Science Talk series this past Sunday.  We continue to be happily surprised by the high level of interest in our project from the McMurdo community - Britney's talk was very well attended and very well received on Sunday.

We were out at the bot house yesterday, and stopped just short of putting ARTEMIS in the water.  We completed a successful test of the lifting system used to put ARTEMIS in the water.  The weight of ARTEMIS (1300 kg in air) and limited ceiling height in the bot house make lifting and rotation for launch and recovery a bit intricate.  Here's a cross-section rendering Bill made showing how it works.

We came back from the field yesterday just in time to fire down some dinner and head over to the McMurdo Station Halloween Party.  Halloween is effectively a high holiday here, with most people preparing months in advance, and many even packing costume elements and special materials with their weight-limited baggage when leaving the U.S.

I was on the wrong end of the preparedness spectrum, but managed to piece together a "Fun Police" costume that ended up being quite enjoyable.  Because of the sunglasses and mustache, many people didn't recognize me, even in conversation.  I issued citations and written warnings for things like "excessive style", but found it was most fun to issue "written commendations" to people with excellent costumes and "meritorious service citations" to people like the DJs, bartenders, and galley staff.

David, one of the Crary Lab Assistants made himself an excellent ARTEMIS costume, complete with thrusters, spooling fiber, docking slot, and headlight.  Those of us on the project were really impressed by it, and really happy to hear the uproar of applause he got during the costume contest.  He was the landslide winner of the Antarctic Theme round.  One of the rec office folks was dressed as the ARTEMIS docking rod, covered in front & back lines of flashing blue LEDs.  It is a great feeling to have other people on station getting excited about our project.

Britney made some waves when she stepped up to the DJ booth, got them to play California Love, took the mic, and rapped the lyrical entirety of that song from memory... an excellent night for the SIMPLE squad.

On Tuesday, we did another Sunfish operation to check out the newly installed culverts beneath the Bot House and the Fish Hut, and to test some navigational software improvements. We were easily able to find both culverts underwater, and fly Sunfish to perform an up-close visual inspection.   

We also used Sunfish to create a 3D sonar map of the area beneath ARTEMIS camp, which can be seen in the video below. Color in the point cloud is mapped to the point's water depth. Both culverts are visible as cylindrical tubes piercing through the ice, and only the bottom surface of the ice is visible - the ice extends about 6m above the ice ceiling. Also of interest is a "belling out" of the Fish Hut borehole at the bottom (green data) from the recent additional melting necessary to install the Fish Hut culvert. Sunfish can be seen holding position about 10m below the ice ceiling.

Rotating around sonar point cloud generated by SUNFISH of the area underneath ARTEMIS field camp.