Atlantis Diaries IV: Eating Iron
Atlantis Diary 4
The bizarre hydrothermal vent field discovered a little more than two years ago surprised scientists not only with vents that are the tallest ever seen –the one that’s 18 stories dwarfs most vents at other sites by at least 100 feet — but also because the fluids forming these vents are heated by seawater reacting with million-year-old mantle rocks, not by young volcanism. The field is unlike any seen before, according to chief scientist Deborah Kelley, a University of Washington associate professor of oceanography, and co-chief scientist Jeff Karson, a Duke University professor of earth and ocean sciences. Both have visited fields of black-smoker hydrothermal vents that scientists have been studying since the 1970s.
Now the two scientists who were the first to travel in a submersible to the field after its serendipitous discovery Dec. 4, 2000, are leading a National Science Foundation-funded expedition to map and further investigate the field. The ‘Atlantis Diaries’ chronicles the expedition returning with 24 scientists onboard an exploration vessel, the Atlantis, during their 32-day expedition that spans April 21 to May 22.
Saturday, May 3
Entry by Bruce Strickrott, DSV Alvin Pilot/Ocean Engineer
It was just after lunch yesterday when I heard Deb Kelley exclaim "We sure are lucky people." We were maneuvering around an extinct carbonate spire, so I was too busy to ponder what her statement meant. She had said the same thing before, but each time I heard these words I was focused on something else.
|One of the carbonate spires that the Alvin pilots and observers have seen at Lost City. Credit: lostcity.washington.edu|
But like an old song that eventually finds its way out of the corners of my mind, her words returned to me that evening. Sitting in my stateroom, watching the fifth re-run of one of the ship’s DVDs ( ‘Goodfellas’ or ‘Matrix’ I can’t recall), what she said in the sub finally sank in. We are lucky to be here in the Mid-Atlantic, exploring areas of the Earth that have never been seen before.
For many of the scientists I meet on the Atlantis, the cruise is a welcome chance to leave the lab, travel to exotic locations, and perform long-thought-out fieldwork. It’s a chance to get out from under the fluorescent lights into the fresh air and sunshine. For myself, and for the other members of the Alvin group and Atlantis crew, this is our home and office for eight months of the year. It would be easy to take all this for granted, and at times I have to remind myself that I actually am getting paid for this.
Thursday was one of those days. On days with scheduled dives, the Alvin group starts preparing the sub at around six o’clock in the morning. That means at about five thirty, I roll out of my bunk to the sound of my alarm’s annoying beep. (I still don’t know how many beeps it has before the alarm stops, but it always seems like too many).
Right above me is my roommate, Noel, jumping out of his bed to the sound of his own annoying beep-beep alarm. It’s our morning dueling-alarm-clock routine. Ten minutes later, after a do-si-do around the single sink in the room, we’re off to work with "it’s too early" bleary-eyed looks on our faces. But every morning I get to see the sunrise, and no two are ever the same. Thursday morning’s sunrise is easy to remember. A line of low hanging cumulous clouds stretched across the horizon. The sun, just beginning to rise, painted the sky blood red with streaks and splashes of burnt orange. It was magnificent.
It’s the simple, subtle things that magnify the experience out here. Different days have different gifts, if you just look for them. Random visits by dolphins or whales, the occasional water spout or wayward flying fish, the color of the water at 60 meters on ascent, the thousands of bioluminescent critters that escort us to the bottom, the chance to see a new vent site or never-seen seascape, the chance to be an active participant in scientific exploration (without all those long years pursuing a PhD) — these are just a few of the regular day-to-day events that have made this the experience of a lifetime.
Thursday’s sunset was just as beautiful as the sunrise. Standing on the starboard side of the aft deck of Atlantis, I gazed at a sea as flat as a lake. The sky had taken on a hue of purple that almost sighed. It was as if the day just didn’t want to quit – that it wanted to squeeze one last drop of color out of its depths before finally giving in to the inevitability of night. I remember thinking that many people never get the chance to see this – you wouldn’t think that the middle of the Atlantic could be so serene and peaceful.
You’re right, Deb, we are lucky. Thanks for the reminder.
Sunday, May 4
Entry by Mitch Elend
Imagery is my gig on this cruise. The first thing I do when I get out of the bunk in the morning is hurry out to take pictures of Alvin before the launch. After a quick breakfast, I rush back out to get pictures of the launch. I never get tired of watching this: A group of people cluster on the back deck, coffee cups in hand, talking and joking. The mood is light yet expectant. A small boat is launched to stand by near the ship’s stern. An Alvin pilot climbs down the ladder into the submersible first, followed by the two scientists who will direct the dive, observe, and take notes. A round vault-like titanium door seals the three aquanauts inside and two skin divers climb atop Alvin and hold on.
Then Alvin is hoisted off the deck by a huge arch crane mounted on the stern of the Atlantis. The submersible is suspended above the water and, when the two divers give the ‘thumbs up’ signal, Alvin is lowered into the ocean. As the sub heaves up and down in the surging water, alarmingly close to the ship’s massive stern, the divers work quickly to unhook the tail line and the heavy rope that bore the weight of Alvin. Once free, the sub drifts back and the swimmers perform their checks, diving periodically to look at the fuselage below, and to release the lines that support the science basket when the sub is above water.
|Two swimmers help recover Alvin after a dive. They jump off before it comes aboard. Credit: lostcity.washington.edu|
When all is ready, word is given to open the air filled ballast tank that keeps Alvin afloat. A spray of water erupts as air escapes and the tank fills. The orange "sail" plunges beneath the waves and Alvin descends, ferrying the three adventurers into the depths.
Onboard Atlantis there is plenty to do. I download all of the launch snapshots from a digital camera and work on yesterday’s imagery. Alvin has five video cameras mounted in various locations on its exterior, and the footage is recorded onto two digital "DVCAM" VCRs inside the sub. Two digital still cameras also are mounted on the exterior, each taking a high-resolution image every fifteen seconds. In addition, there are two handheld digital cameras inside the sub that the scientists and pilot use to take pictures through the three small round windows.
Videotapes have to be duplicated, and the gigabytes of digital still imagery have to be downloaded, filed, backed up, time-stamped, and made accessible to the scientists aboard. This cruise promises a lot of stunning imagery, and I can’t wait to start piecing together mosaics of digital stills showing the bizarre white carbonate structures of the Lost City.
When the dive is over around 3:30PM, Alvin drops its weights and returns to the surface. The sub is sighted, the ship’s whistle sounds, and a small boat with skin divers aboard charges out to meet it. The recovery is pretty much the reverse of the launch except that this time the divers ride Alvin back up and leap off the sub as it reaches the top of the hoist.
Monday, May 5
Entry by Billy Brazelton
I like weird stuff. Especially if it’s weird biological stuff. Aliens, for example, would be very weird biological stuff. Unfortunately, there is a shortage of aliens available for graduate students like me to study, so instead I am doing the next best thing: searching for weird life forms in a weird environment on Earth – the Lost City.
So how do you go about searching for new, weird life forms? The first step is to take Alvin down to the Lost City and collect rocks and water samples. When Alvin comes back to the ship, there is a feeding frenzy of scientists trying to grab the samples that they need for their research. Sometimes it’s important to get your samples as quickly as possible before they degrade or become contaminated, so the scientists hurry to sample and process the rocks–sometimes it can get a little hectic.
The weirdest organisms are always the microorganisms – the bacteria and archaea – so that’s what I’m looking for in the precious samples allowed to me.
|Some culture tubes in one of our incubation ovens. They’re hot! Credit: lostcity.washington.edu|
Most of the work that Mausmi Mehta and I are doing during the cruise involves adding rocks and water samples to small tubes containing nutrients. We’re hoping that the nutrients will encourage microorganisms from the Lost City to grow inside the tube, but this has been problematic because we have no idea what nutrients the Lost City microbes will need. We don’t know what they like to eat. They might eat pizza and peanut butter like we do, but there doesn’t seem to be much pizza or peanut butter in the Lost City, so any life there must be eating something else.
Microbes in other hydrothermal vents are known to eat iron, sulfur, carbon dioxide, or even hydrogen sulfide (which has the smell of rotten eggs). If we tried to eat that stuff, we would die. The chemists say that there is an unusual amount of methane gas at Lost City, so we think there might be organisms excreting or eating methane there.
But we really have no idea, so I’m trying pretty much everything. I’ve tried at least 100 different nutrient combinations so far. It’s still too early to know how successful we’ve been at finding the right food, but we do know that Lost City microbes like to grow at 90° C (that’s 194° F, almost the boiling point of water). If I put them at anything less than that, they stop growing.
When we notice that something might be growing in the tubes, we look at it under the microscope, but unless the microscope is very powerful (not the kind you bring on a boat), they all look like black specks. So when we get back to land, we will extract DNA from all of the samples we’ve collected. After we determine the sequence of this DNA, we will be able to say which species are at the Lost City – and whether any of them are new, weird discoveries.
The project includes scientists, engineers and students from the University of Washington, Duke University, Woods Hole Oceanographic Institution, U.S. National Oceanic and Atmospheric Administration, Switzerland’s Institute for Mineralogy and Petrology and Japan’s National Institute of Advanced Industrial Science and Technology. Collaborators include: Jeff Karson, Duke University, Co-PI and diver during the discovery; Matt Schrenk (an astrobiology graduate student at the UW School of Oceanography); P.J. Cimino (a NASA Space grant undergraduate); and John Baross, also a faculty member in astrobiology and oceanography.
Related Web Pages
Atlantis Diaries XI: Encore
Atlantis Diaries X: Reaction Zone
Atlantis Diaries IX: Rescue
Atlantis Diaries VIII: Science Basket
Atlantis Diaries VII: Poseidon’s Excellent Adventure
Atlantis Diaries VI: Portal on the Past
Atlantis Diaries V: Hump Day
Atlantis Diaries IV: Eating Iron
Atlantis Diaries III: Exploring Alien Eco-Regions
Atlantis Diaries II: First Dive
Atlantis Diaries I: Leaving Port
Life from Rocky Reaction
Lost City Expedition
Discovery of Lost City vent field-Univ. Washington
Univ. Washington School of Oceanography
Life without Volcanic Heat