Speed 0.0 knots
Course 254°
Location Drygalski Inlet (-64.73474833, -60.58166167)
Depth 690 meters
We spent another couple days near the Drygalski Glacier and the weather has gotten quite cold. It's well below freezing and with the windchill, it's about 30 degrees below zero (in C or F). When we're on deck we wear these nice insulated pants and coats, but I still haven't figured out how to keep my hands warm inside my gloves. My best solution so far is to add a handwarmer inside, but my fingers still feel like they're going to freeze after 10 minutes or so. Just know that it's cold and we can tell that winter is coming.
Megacore
One of the messiest instruments on deck is the megacore. It's composed of 9 plastic meter-long tubes arranged in a square pattern. The whole device is dropped to the ocean floor and it usually collects about a foot of mud in each tube.
Jeremy Lucke guiding the megacore into place on deck
Below you can see what the tubes look like when they are full of mud. On the far right, if you look carefully you can see the door at the bottom that slides shut as the megacore is raised to the surface. This keeps the marine sediment from falling out as the tubes are raised to the surface.
Megacore tubes full of marine sediment
Once the megacore is on deck, the tubes have to be carefully removed. The scientists take them inside (no one wants to work out in the bitter cold) to mudbust! Mudbusting is the common term around here for sampling these columns of mud. The megacores mostly belong to the benthic ecologists who are looking for small organisms that live in the top 10 cm of the ocean floor. First the column is put on a pedestal that pushes the mud up to the top of the tube. Next small slices of the mud are cut off with spatulas or thin metal sheets.
Michael Derocher (left) and Jackie Mueller (right) mudbusting the megacore
Usually, only the first 10 cm of marine sediment is saved. That leaves a lot of leftover mud that we throw overboard off the back deck. As you can see, it's messy work, but it's actually quite fun.
Me carrying a bucket of mud leftover from the megacore (photo taken by David Honig)
After all this hard work, scientists still have to sieve the mud to get rid of all the dirt. Below you can see some of the creatures they found once the sediment was removed. Try to find the polychaete worm (the one that looks like it has feet) and the sea star below.
Organisms found in a megacore (photo take by Pavica Srsen)
Lately, we've had some bad luck getting the megacores to collect sediment. Sometimes the ground is uneven or too sandy to collect good samples. Every once in awhile, they even hit a rock on the ocean floor. Ooops!
What happens when the megacore hits a rock in the sediment
Good thing we have lots of backup tubes!