launch today's slideshow

jason deployment video

Each Jason launch is a carefully choreographed dance involving engineers, technicians, pilots, and Atlantis crew members. In this video, follow along as the remotely operated vehicle is deployed from the ship for the first time during our expedition.

Today's Weather
Lat: 9° 49.880 N
Long: 104° 17.592' W
Winds: NE; 8.52 knots
Air Temp: 26.9°C, 80.4 °F
Bar. Pressure: 1013.7 mbar
Humidity: 78.9%
Sea surface temp: 27.4°C; 81.3 °F
Visibility: Unlimited

what's to eat?

Puzzle Activity

NEW! Teacher Activity Resources

The following teacher resources were contributed by Carolyn Sheild, 7th grade Life Science Teacher, at Clarke Middle School, Lexington, MA

Day 2 slideshow
An introductory worksheet for Expedition 15
MS Word file | PDF file
Day 3 slideshow
Daily update worksheet for Expedition 15 Days 1 & 2
MS Word file | PDF file


The Pressure Is On

January 6, 2014 (posted January 7, 2014)
by David Levin

One by one, researchers file slowly into the ship's library to make a decision. For the last four days, these scientists have been working with the Jason team day and night to collect samples on the seafloor, and other than a few small glitches, they're ahead of schedule. Today, they’ve reached the end of their initial dive plan for Jason, so the scientists are meeting to discuss their next steps.
So far, the researchers have gathered fluid samples and have measured the chemistry and flow rate of fluids coming from seafloor vents. They’ve collected samples of organisms as well, from microbes, to tubeworms, to giant mussels. They've even taken pieces of the vent structures themselves—delicate, glittering columns of minerals that slowly build up as the vent fluid gushes out of the seafloor.

While elevators can deliver most of the samples Jason takes, they don’t work for everything. The remotely operated vehicle's "slurp sampler," a sort of underwater vacuum that sucks up small organisms, deposits its samples into tanks deep inside the vehicle that can’t be removed and put on an elevator. So after a brief conversation, the researchers agree: Jason will have to surface.

Although the vehicle is taking a short breather, the teams of scientists aboard the Atlantis are still going strong. Over the last few days, they've filled 15 Isobaric Gas-Tight (IGT) samplers with fluid from Crab Spa, one of the main vents they’re studying on this expedition. These samplers collect the fluid as it comes out of the mouth of the vent and use a titanium piston inside to compress it on the way to the surface. In this way, the fluid and the bacteria inside it stay at the same pressure as fluid at the seafloor, which can reach more than 3,000 pounds per square inch.

This may not seem like a big deal, but keeping the fluid pressurized all the way to the surface is essential to the experiments that graduate student Jesse McNichol and postdoctoral investigator François Thomas are running. If the pair released the pressure, the gases inside the fluid would bubble out, changing the fluids’ chemistry and possibly killing some of the microbes.

Under pressure

When the IGT samples arrive in the lab, Thomas and McNichol will keep them pressurized and essentially under the same conditions that exist at the seafloor, and coax the bacteria inside the IGTs to grow. Over the course of 24 hours, they'll add nutrients and gases to the fluid to see how those microbes react.

Like finicky houseguests, different species of microbes have their own unique preferences. Some are comfortable only at a specific temperature; others are picky eaters, and dine only on specific chemicals, like hydrogen sulfide.

Over the course of their experiments, McNichol and Thomas will try to figure out the microbes’ tastes by injecting hydrogen and oxygen gas into the samplers, as well as chemicals such as nitrate and formate, a common substance at the vents. In the process, some bacteria will thrive, and others wither as each new chemical is added. "What we’re basically trying to do in these experiments is figure out which chemicals these species of bacteria like to eat or breathe,” said McNichol.

As the experiment moves forward, the pair will test the fluid every eight hours. After a day goes by, they'll empty the IGT to count the number of bacteria that have grown inside. Once the bacteria use up the nutrients and vent chemicals inside each device, they will eventually die off. The scientists will preserve the cells and bring them home to Woods Hole for further study.

Recreating the bottom       

While McNichol and Thomas are prepping samples for study back on land, postdoc Ileana Pérez-Rodríguez and geochemist Dionysis Foustoukos are taking a slightly different approach. They've brought their entire lab with them from Washington, D.C., and have painstakingly reassembled a small pile of equipment here on the ship. [You can see a time lapse video of them setting up here].

Pérez-Rodríguez leans over a jumble of tubing, pumps, and cables, and stares intently at a metal frame in the middle of a table. It holds a tall cylinder wrapped in white foam insulation. Inside it, she’s growing vent bacteria.

Like McNichol and Thomas’ experiments, this one is being carried out at high pressure—but instead of using an enclosed system, the researchers are trying to simulate the conditions at the bottom of the ocean, where vent fluid moves continuously over the microbes that live near the sea floor.

“We’re basically recreating a vent right here in the lab,” said Foustoukos.

With the help of undergraduate student Matt Rawls, the researchers hook an IGT sampler to their shrouded contraption. Over the next few days, they’ll let the pressurized vent fluid inside trickle over their microbes. Then they’ll alter the conditions inside the system by changing pressure and temperature, and watch how the microbes react.

The scientists are hoping to recreate conditions not only at the vents themselves, but below the seafloor, where the vent fluid comes from. They think that environment hosts a huge number of microbes, but it’s nearly impossible to do experiments on them down there.

“We don’t really know what sorts of organisms live under the seafloor, or how they contribute to the chemistry of the vents,” said Foustoukos. The experiments being done here on the Atlantis may offer some clues.


brennanJames Brennan is Atlantis’ Communications and Electronics Technician, or “ComET.” He makes sure all the communications on the ship, from radios to satellite phones, are up and running every day. He’s been a ham radio operator since he was in eighth grade, and is a self-described radio nut—so in other words, he’s tailor-made for this job. Read the interview »


[ Previous update ]   [ Next update ]


[Back to top]