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Diane Langmuir (REVEL 2003, middle school science teacher)
Dwight-Englewood School
Englewood, New Jersey

How do the scientists decide where to put the instruments? What criteria are used? Who decides?
Wise placement of instruments depends on what the instruments are, and what the question is that a scientist is asking. Remember that as we gain more insight into a process or system, we change our ideas and therefore we change the questions that we ask. This might influence the experimental design of instrument deployment.

One example is seismology. If the question is, “where does nearby deformation take place and how often does it occur,” then you would want to place your seismometers, which measure the rapid, oscillating movement of rocks, near the zones where faults move. This is usually near the edges of tectonic plates.

If, as a scientist, you are more interested in how the water in the ocean flows from one place to another, then you need to have current meters in places to allow measurement of that flow and how it changes with time.
As you can see there is no simple answer to the question of where to put the instruments. The specific criteria depend on the kinds of questions the scientist is asking and it also depends upon what scales of time and space the scientists wish to illuminate with their investigation.
John Delaney
Co-chief scientist
Marine Geology and Ocean Observatories
University of Washington

How does the scrubber work that cleans the air of CO2 on Alvin?
The CO2 scrubber is an electric device like a vacuum cleaner that hangs in the rear of the sub’s cockpit. An electronic monitor provides a read-out of the level of CO2 in the cockpit atmosphere and it is the pilot's responsibility to periodically check that the CO2 is not too high. When necessary, the CO2 scrubber is turned on and the air is sucked through a canister of special pellets that react with the CO2 to absorb and remove the CO2 from the atmosphere. Two new canisters are placed in the cockpit before each dive and the used ones are removed after each dive. In addit9on, Alvin carries two emergency canisters of lithium hydroxide to use for CO2 removal if the sub needs to stay down longer. The combination of these four canisters provide for 72 hours of CO2 removal.

George Meier
Electrical Technician, Alvin group

If the boiling point of water is 100 degrees C at sea level, what is the boiling point of the water down at the ridge where the pressure is so high? How does the mineral content change the boiling point?
The boiling point of water depends mostly on a combination of temperature and pressure—and a little on how salty the water is. At the mid-ocean ridges where the pressure is so great—it increases 1 atmosphere for every 10 m depth—the boiling point of water is about 420°C at depths of 2500 m to 3000 m. Since there is not much variation in salinity—the dissolved minerals in seawater—this does not have such a greateffect as the pressure.

More on this topic can be found at the “Deeper Discovery” infomod on the Dive and Discover website.

Susan Humphris
Senior Scientist
Woods Hole Oceanographic Institution

What is the full classification of the tubeworms?
The Latin name of the best known tubeworm is Riftia pachyptila. It belongs to a group of worms known as Vestimentifera. Riftia can be up to 8 feet long, and a smaller 3 foot tall version lives off the coasts of Washington and Oregon, where we are working now.

Jim Holden
Microbiologist
University of Massachusetts

Are there really nutrients the bacteria manufacture?
Tubeworms lack a mouth, a digestive tract, and an anus. Instead, they have a kind of sack inside of them that is full of a specific kind of bacteria. The worm has gills, the red part of the worm that you see sticking out of the top of the tubes that it uses to breathe in oxygen and another chemical called hydrogen sulfide, which smells like rotten eggs.

The worm’s blood delivers these chemicals to the bacteria that then converts it into energy and the molecules necessary for growth. The bacteria then share these compounds with the worm. So, the bacteria get a nice place to live and the worm gets energy and nutrients from the bacteria. This kind of relationship is known as symbiosis.

Jim Holden
Microbiologist
University of Massachusetts

We absorb some things manufactured by bacteria in our gut. Did our gut somehow evolve from tubeworms?
We also absorb certain chemicals in our body that are manufactured by bacteria living in our gut. However, our gut did not evolve from tubeworms. Rather, this demonstrates that similar processes can occur in very different organisms.

Jim Holden
Microbiologist
University of Massachusetts

How do the scientists feel about their work and what they are contributing to our understanding of our world?
There are many mysteries on our planet and in our universe that are waiting to be revealed. With each new discovery, we learn more about our world and our place in it. We humans love to explore, learn new things and apply what we learn to our lives. The work that we scientists do is not just for ourselves but for everyone on the planet to learn from and enjoy.

Jim Holden
Microbiologist
University of Massachusetts

What advancements will be made with all of this new gained knowledge?
We hope that there will be many advancements. We hope to have a better understanding of how the earth works, especially with regard to plate tectonics and the volcanoes on the bottom of the ocean. Furthermore, we hope to discover new forms of life that will teach us new things about biology, including new things about our own bodies. We hope to learn how to look for unusual life, which will help us look for life on other planets and moons. We also think that some of the bacteria in these deep-sea volcanoes are very, very old and that they may tell us what life on earth was like before there were any plants or animals on it. Lastly, the bacteria that we are discovering are used by industries on land that provide us with things we use every day, such as oil, sweeteners for soft drinks, proteins that make our clothes cleaner, and ways to make copies of DNA in a test tube.

Jim Holden
Microbiologist
University of Massachusetts

What does the earthquake information tell us? How does it relate to the whole system of hydrothermal vents?
Earthquakes are very common along ridge crests or spreading centers like the one we are working on during this cruise. There are many things that earthquakes can tell us about the rocks below the seafloor. In some cases, using lots of earthquakes, including some artificial ones, we can determine the depth to the molten rock, or magma chamber, below the seafloor along a spreading center.

This heat sources is usually very important in raising the temperature of the seawater that percolates down into the cracks below the seafloor and then becomes buoyant, rising back to the surface like a hot air rising. The magma chamber is often one or two kilometers below the seafloor and we believe many fractures and faults at the seafloor penetrate almost to the top of that red-hot reservoir of potential lava.

The other thing that earthquakes do is keep the fractures from clogging with mineral deposits by shaking and breaking the deposits along the fractures, which are upflow channels for the hot rising fluid. This keeps the hydrothermal systems active for many decades until the magma chamber solidifies or until spreading moves the rocks away from the hot centralized spreading center.
John Delaney
Co-chief scientist
Marine Geology and Ocean Observatories
University of Washington

Does everybody get along (on a cruise)? Is it just one happy family? What if you don't like somebody or disagree about what to do on some experiment? Do you guys have any fun? What are some of the funny moments or things that have happened? It all looks so serious.

You have asked a complex set of questions and the answers are even more complex. To address the answer you have to understand the way a ship is organized. Everyone has a very specific full time job and we are all dependent on each other.

The ship is less than 300 feet long and no more that about 70 feet wide. It is a very small world, and you can not get off and go into town for a while. Day in and day out, you are here and you have to interact with people to get your own work done. So everyone is very careful to be polite and considerate, as well as conscientious about performing their job.

The captain is in charge when the vessel is in any danger, and he or she makes major decisions regarding safety or overall ship activities. The chief scientist is in charge of the science that is done. Both of these people work closely and very well with their ship mates to see that everything runs smoothly. When there are disagreements, these two people are the ultimate arbitrators—and the system works very well.

We are all very excited about what we are doing out here and there is usually a very positive, upbeat attitude on the part of most people. That does not mean there are no problems. We are here to complete the scientific work that we have been funded for and to a first approximation, continued funding on a project depends on being successful at sea, so there can be a lot of pressure. Things can get difficult, for example, when the weather turns bad for several days. Then we lose Alvin dives and someone’s science does not get done.

Usually the groups try to resolve issues by sitting together to discuss the best solution, but ultimately, at sea, the captain and the chief scientist are in charge and make the decisions if necessary, and everyone who comes out here agrees to that implicitly by coming on board at the beginning.

Your question about fun is important. First point, most of us are doing this because we love what we are doing. It is not a 9 to 5 job. We work long hours, but much of what we do contributes to expanding our understanding of how the world works and we are excited about seeing things for the first time, or gaining new insights no one has ever had before.

When we are not working, we do have a number of pastimes. Exercising is one. There are machines and long walks to take on the rolling, pitching decks. There is also a library on board, stocked with all kinds of books. We talk a lot to one another, exploring new friendships and deepening others, there are of course practical jokes, and lots of stories, and laughter.

Many cruises have a ping-pong tournament that is very competitive. One thing that I am looking forward to is the wonderful barbeque we will have June 5, when the cooks prepare a lavish picnic on the back deck and everyone comes to the party.

John Delaney
Co-chief scientist
Marine Geology and Ocean Observatories
University of Washington

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