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An overview of the detailed exploration of the gakkel ridge

Full Bio Photo credit: Courtesy Tim Shank Dr. He earned a B. His current research focuses on understanding the ecology and evolution of species living on the ocean floor. Shank's lab at Woods Hole investigates deep-sea habitats by studying both the molecular genetics of the creatures that live there and the physical, chemical, geological, and ecological processes that affect them. Shank has participated as chief scientist, principal investigator, or graduate student on over 30 oceanographic cruises using deep-submergence vehicles, including more than 60 dives in Woods Hole's Alvin submarine.

His most recent field expeditions include a 2007 remote exploration of the Arctic Ocean's Gakkel Ridge, and a 2009 voyage that successfully sent a robotic vehicle over six miles down to the Mariana Trench, the deepest part of the world's oceans.

When he's not on the high seas, Shank is an avid piano player and Revolutionary War buff. Thanks to his line of work, he no longer eats shellfish. Shank, We know the ingredients of life here on Earth, but what if life on another planet is made up of different chemical building blocks? How do we create tools to sniff out what we're not even sure we're looking for?

  1. Suni Lewisson, Seattle, Washington Shank. There are hypotheses and theories presented each year refining and exploring the boundaries of the conditions, timing, and how it might have happened.
  2. Seeing the most otherworldly and beautiful glassy seafloor terrain I have ever seen. The full map of Earth's continents can be made almost daily from satellite images.
  3. Dear Julie, This is an interesting question and the short answer would appear to be "nothing", given the remoteness of these ecosystems directly to atmospheric climate. The Gakkel Ridge has been geographically and oceanographically isolated from other mid-ocean ridges for at least the last 28 to 53 million years.
  4. Scientists locate apparent hydrothermal vents off antarctica a detailed map of ocean a team of scientists to the gakkel ridge between greenland and.
  5. According to many microbiologists, less than 1 percent of Earth microbes have been cultured—the rest may be considered "unculturable". The Arctic Ocean is a long way from any rescue if something happened to the ship!

S, Cleveland, Ohio Tim Shank: This reminds me of the story where native North Americans standing on the New England shore did not see the Mayflower approaching land because their minds were not conditioned to "see" a large ship on the water. Scientists have asked whether the search for life should really include alternative forms of life, but if we can't define what that full range of alternatives might be, then how can we search for them?

The problem with these is often either a structural one ability to maintain a complex atomic configuration or a reactive one they react with other elements to break down quickly. The techniques microbiologists use to detect life on Earth, like staining for DNA, sequencing DNA, and culturing microbes in the lab, assume that the target microbes have the normal biochemistry. According to many microbiologists, less than 1 percent of Earth microbes have been cultured—the rest may be considered "unculturable".

This means that an alternative form of microbial life even ones similar to the ones we know may go readily undetected. Interestingly, astrobiologists refer to these forms of life as "shadow life", and that constructing and testing means of detecting this life is particularly more difficult on an Earth contaminated by pollution than on other planets. Biochemists are an overview of the detailed exploration of the gakkel ridge thinking that a promising future is to explore extreme environments that are beyond the reach of conventional life, such as ultra-dry deserts, ice sheets, the upper atmosphere, or the hottest hydrothermal vents.

The reality is that we can search for the realm of what we do know, at least as a first pass. How soon do you think technology will allow us to go to Europa to look for life under the ice? Carolyn Sheild, Waltham, Massachusetts Shank: Dear Carolyn, Most estimates suggest that the full technology to deliver a vehicle that will land on the icy surface, tunnel through the 80 to 170 km of ice and deploy itself in the Europan Ocean is more than 15 years away.

This is a highly rough estimate in my opinion as this timing in many ways depends on the space exploration priorities set forward by governments around the world. You say in the show that essential ingredients for life include water, rock, and a heat source. Isn't it possible that life as-we-don't-know-it may have formed without, say, water?

  • Also, in methane and hydrocarbon, the essential elements of life as we know it , amino acids, could not freely exist;
  • Biochemists are now thinking that a promising future is to explore extreme environments that are beyond the reach of conventional life, such as ultra-dry deserts, ice sheets, the upper atmosphere, or the hottest hydrothermal vents;
  • Shank, What did it feel like to be exploring a place that no one had ever seen before?
  • Is there anything like it other places on Earth?
  • The problem with this is that the temperature at which these exist is more than 100 degrees below zero.

Have researchers looked into that possibility, and, if so, what have they found? Joaquin Franklin, Pennsylvania Shank: Dear Joaquin, Yes, some planetary scientists have pondered that liquid ammonia, methane, or hydrocarbons might be capable of incubating the formation of life. As you may know, water has a variety of properties that allow and even promote life, including being a medium with different phases that facilitates chemical reactions, the very existence of molecular structures, dissolving byproducts, and the long list goes on.

Methane and hydrocarbons can be highly abundant on other planetary bodies, like forming lakes on Titan. The problem with this is that the temperature at which these exist is more than 100 degrees below zero. Chemical reactions would likely be either non-existent or too slow to support the machinery of life as we can conceive of it.

Also, in methane and hydrocarbon, the essential elements of life as we know itamino acids, could not freely exist. For these reasons, scientists in general currently believe that life finds water essential. Hi, Tim, Since the expedition, have you learned anything more in the lab about the yellow microbial fluff on the Gakkel Ridge? Is there anything like it other places on Earth? Danielle Kennedy, Boston, Massachusetts Shank: Dear Danielle, Yes, we have learned a great deal more.

There is a high diversity of microbes living in the mat, many iron-loving. This makes sense given our observations of "rust-colored" alteration of the rocks around the mats. They are relatively different from most other microbial species living at vents along the global mid-ocean ridge system. In general, they resemble closely those microbes found in deep-sea iron-rich environments similar to the Gakkel Ridge depth of 4000m in the Pacific.

  1. The change in deep-ocean chemistry will change levels of oxygen that vent animals require and pH that would impact the ability of certain animals to physiologically function properly, like make their shells. I know some Navy subs can cruise below the polar ice, and a Russian one even planted a flag on the ocean floor below the North Pole.
  2. The gakkel ridge is an ultra-slow a series of targets for future ridge-crest exploration were but no detailed investigations of the underlying.
  3. We still want to know why animal life is not more abundant in the mats if it is an effective food source. Recently hydrothermal vents have been discovered at twelve sites located on the gakkel ridge hydrothermal field on the juan de fuca ridge and exploration.
  4. Along with curiosity, the thirst and thrill for discovery is what drives scientists to think past what we know.

We have a lot more to learn. We still want to know why animal life is not more abundant in the mats if it is an effective food source. Shank, What did it feel like to be exploring a place that no one had ever seen before?

What were the most exciting moments for you personally during the expedition? Dear Anonymous, The thrill of true exploration is hard to put into words.

An overview of the detailed exploration of the gakkel ridge

I have been very fortunate to have had many opportunities in my profession to explore unknown places on Earth, and feeling what any of us have felt in a completely new environment just take a walk in unexplored woods with a flashlight at night. I recently returned from an expedition where we utilized a high-tech robot to reach the bottom of the Mariana Trench, the deepest place on Earth—over 7 miles deep, deeper than Mount Everest is high.

Along with curiosity, the thirst and thrill for discovery is what drives scientists to think past what we know. I have had more than 40 research expeditions, and the ones I always love and remember most are those where we drove past the boundaries of the map, past the boundaries of our knowledge.

The Gakkel Ridge stands out as perhaps my most favorite because of the challenges we overcame with building new vehicles and making them work with all kinds of solutions from complex wiring to using C-clamps to hold the hydraulic system together.

Gakkel Ridge: Expert Q&A

Seeing the most otherworldly and beautiful glassy seafloor terrain I have ever seen. There is no place on Earth that looks quite like the Gakkel Ridge seafloor 200 miles from the North Pole. I once thought that Vasco de Gama, Ferdinand Magellan, and other explorers had found all there was to discover.

The full map of Earth's continents can be made almost daily from satellite images. However, less than 1 percent of our ocean floor has been mapped over the past 140 years. Shank, Are scientists any closer to figuring out how life might have begun on Earth, that is, how the very first life-form made the leap from a bunch of chemicals to a single cell? Tyler Doucette, Florida Shank: Dear Tyler, This is a good question and a hard one.

I think we "know" more today about the possible and likely conditions, the timing, and the sequence of events that are considered to be the "chemical evolution of life". There are hypotheses and theories presented each year refining and exploring the boundaries of the conditions, timing, and how it might have happened.

I am not an expert on this, but I would encourage you read a recent popular article in Discover Magazine that explains some of the most compelling experiments ever conducted in science: Was the fact that the Gakkel ridge is similar to Europa the main reason you guys went there, or were there other reasons to explore it?

Dear Anonymous, The similarity of the ice-covered oceans above a mid-ocean ridge in the Arctic and on Europa is just one of the reasons why we went there.

  • What were the most exciting moments for you personally during the expedition?
  • Suni Lewisson, Seattle, Washington Shank;
  • Scientists have asked whether the search for life should really include alternative forms of life, but if we can't define what that full range of alternatives might be, then how can we search for them?
  • Search results 1153 each set includes an overview, ten to fifteen this article describes robots that are helping scientists explore the gakkel ridge;
  • Search results 1153 each set includes an overview, ten to fifteen this article describes robots that are helping scientists explore the gakkel ridge.

As an evolutionary biologist, my goal was and still is to find out how life living on the deep Arctic seafloor evolved in what we believe to be complete isolation from communities in other oceans. There are very few places in our ocean that we know have been isolated in the past.

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The Gakkel Ridge has been geographically and oceanographically isolated from other mid-ocean ridges for at least the last 28 to 53 million years. By this time the Arctic seafloor starting spreading with likely hydrothermal venting activity[and] the deep Arctic Ocean was isolated to the north Atlantic by a shallow sill or saddle and the shallow Bering Strait. Whatever animals adapted to life in "toxic" thermal springs two and a half miles below the ocean surface did so in isolation, likely resulting in new life forms with novel adaptations.

The probability of discovering novel species, physiologies, ecologies, and symbioses animals living with microbes that would detoxify the toxic fluids is extremely high. Consequently, exploring for and locating life on the Gakkel Ridge could and may still reveal fundamental clues as to how evolution has produced such wonderful biodiversity in our oceans. How is that so? Don't ocean currents flow all around the globe? The Arctic's connection with the Pacific Ocean is narrow and shallow, so the major exchange of water is with the Atlantic Ocean through the Fram Strait.

Atlantic surface waters communicate freely and an overview of the detailed exploration of the gakkel ridge strong subsurface current brings warm water from the Atlantic into the Arctic basin, [but] exchange of deeper waters is prevented by sills and submarine ridges. The bottom of the Arctic Ocean is very cold and relatively stagnant. So the isolation is due to the shallow Fram Strait, the narrow passage between Greenland and Spitsbergen that serves as a shallow choke point for water getting into and out of the Arctic from the Atlantic.

The other major choke point is in the southern Chukchi Sea, which provides only shallow northern access to the Pacific Ocean via the Bering Strait between North America and Russia. What's the deepest you've ever been in a submarine? Dear Anonymous, My deepest dive was in the submersible Alvin along the Mid-Atlantic Ridge where we dove to a depth of 3730m almost 2.

The deepest that Alvin can currently dive is 4500m, and the deepest hydrothermal vent site we know of so far just north of the equator in the Atlantic is 4150 meters deep. What is the strangest thing—animal or otherwise—you've ever encountered on the ocean floor? Also, at these same depths, I've unfortunately seen toilets, piping, beer cans, magazines, and even cigarette butts.

Most recently, I've seen pieces of plastic at almost 7 miles down. Shank, What can studying deep-sea ecosystems like those at hydrothermal vents tell us about the general health of the world's oceans?

The "climate" at those depths seems pretty similar cold and dark no matter where you are on the planet, so I'm wondering if global climate change has a noticeable effect on those regions. Julie Schofield, Portland, Oregon Shank: Dear Julie, This is an interesting question and the short answer would appear to be "nothing", given the remoteness of these ecosystems directly to atmospheric climate.

  • This makes sense given our observations of "rust-colored" alteration of the rocks around the mats;
  • From Earth's geologic past, we know that volcanism has a tremendous affect on the health of our planet, frankly impacting our atmospheric chemistry, controlling mass extinctions of terrestrial and marine life;
  • You say in the show that essential ingredients for life include water, rock, and a heat source;
  • By this time the Arctic seafloor starting spreading with likely hydrothermal venting activity , [and] the deep Arctic Ocean was isolated to the north Atlantic by a shallow sill or saddle and the shallow Bering Strait.

The reality is that these ecosystems are intimately connected to volcanic processes on Earth—they have evolved to live on earth's largest linear volcano, thriving in eruptive areas where lava frequently spews out on the seafloor and where seafloor vents are created. From Earth's geologic past, we know that volcanism has a tremendous affect on the health of our planet, frankly impacting our atmospheric chemistry, controlling mass extinctions of terrestrial and marine life. So, while a close connection between monitoring the "health of our ocean" and the state of hydrothermal vent ecosystems has yet to be made, it seems clear that increasing global oceanic temperatures are changing the acidity of the ocean shallow and deep and the ability of the deep ocean to store carbon.

The change in deep-ocean chemistry will change levels of oxygen that vent animals require and pH that would impact the ability of certain animals to physiologically function properly, like make their shells. Shank, Weren't you a little nervous about sailing through miles of solid ice? The Arctic Ocean is a long way from any rescue if something happened to the ship!

Suni Lewisson, Seattle, Washington Shank: Dear Suni, Yes, our location, less than 200 miles from the north pole was remote, and there are many courageous historical accounts of being shipwrecked and lost on the Arctic ice for months these stories are frequently discussed when "up on the ice".