Extreme Shrimp May Hold Clues To Alien Life On Europa

HughPickens.com writes: Scientists at NASA's Jet Propulsion Laboratory are studying a mysterious ecosystem at one of the world's deepest undersea hydrothermal vents to get clues about what life could be like on other planetary bodies, such as Jupiter's icy moon Europa, which has a subsurface ocean. At the vents, tiny shrimp are piled on top of each other, layer upon layer, crawling on rock chimneys that spew hot water. "You go along the ocean bottom and there's nothing, effectively," says Max Coleman. "And then suddenly we get these hydrothermal vents and a massive ecosystem. It's just literally teeming with life." Bacteria, inside the shrimps' mouths and in specially evolved gill covers, produce organic matter that feed the crustaceans. The particular bacteria in the vents are able to survive in extreme environments because of chemosynthesis, a process that works in the absence of sunlight and involves organisms getting energy from chemical reactions. In this case, the bacteria use hydrogen sulfide, a chemical abundant at the vents, to make organic matter. The temperatures at the vents can climb up to a scorching 842 degrees Fahrenheit (450 degrees Celsius), but waters just an inch away are cool enough to support the shrimp. The shrimp are blind, but have thermal receptors in the backs of their heads.

According to the exobiologists, these mysterious shrimps and its symbiotic bacterium may hold clues "about what life could be like on other planetary bodies." It's life that may be similar—at the basic level—to what could be lurking in the oceans of Europa, deep under the icy crust of the Jupiter moon. According to Emma Versteegh "whether an animal like this could exist on Europa heavily depends on the actual amount of energy that's released there, through hydrothermal vents." Nobody is seriously planning a landing mission on Europa yet. But the European Space Agency aims to launch its JUpiter ICy moons Explorer mission (JUICE) to make the first thickness measurements of Europa's icy crust starting in 2030 and NASA also has begun planning a Europa Clipper mission that would study the icy moon while doing flybys in a Jupiter orbit.

Comments

Re: Most expensive sushi ever

[K. S. Kyosuke]

Considering the Japanese penchant for rare sea delicacies, this could certainly provide a boost to their space program. Unless they get overtaken by the Chinese in case we find alien sea cucumbers on Europa, of course.

Re:In Reverse

[pr0nbot]

Surely "mild" and "harsh" are subjective? From the point of view of a molecule, what constitutes "harsh"?

Perhaps evolving life in high temperatures turns out to be easier than at room temperature, e.g. because there's more free energy around.

Re:In Reverse

[Brett Buck]

In this case I would say it was pretty sure that's what happened, but only because it was already alone.

I would expect life would flourish where the exploitable energy exists, and be more diverse where there is more of it.

Re:Most expensive sushi ever

[rubycodez]

all these shrimp are yours, except Europas, eat no crustaceans there

Re: In Reverse

[TapeCutter]

Deep sea vents were discovered when I was in my 20's before that we used to think abiogenesis had something to do with lightning hitting a mud puddle. The evidence that life formed around such vets on Earth is strong but inconclusive. Fatty acids from clay in the vent spontaneously form primitive cell membranes (in vents and mud puddles). Sulphur provides chemical energy, porous rock around the vent provides a sponge like scaffold for life to take root and extract passing nutrients. Most importantly the vents are predictable, the deep, still water stabilizes the temperature gradient. Convection currents cycle the fatty cells through the gradient allowing different chemical reactions within the membrane to synchronize themselves to the thermal cycle (much the same as plants match the cycle of night and day). If that really is how life got started then it's likely that primitive cells are still being spontaneously created near these vents today, the practical problem for scientists researching this idea is finding them before evolved life such as shrimp eat them.

Europa has all these conditions and like Earth it's ocean is also oxygenated at the top. Oxygen is vital for multicellular life on Earth, collagen (the stuff that holds individual cells together as multicellular critters) cannot form in an oxygen poor environment. Oxygen in Europa's ocean is replenished differently than it is on Earth. On Europa's surface strong radiation from Jupiter knocks the H2 off the ice and out into space, the free oxygen is returned to the ocean via plate tectonics. Personally I would think it very odd if we didn't find single celled life in Europa's ocean, at the very least it would force Science to radically rethink the conditions that lead to abiogenesis on Earth. What I'm interested to find out is whether life on Europa uses the same self-replicating molecules used by life on Earth, but I doubt I will be around to hear the answer..