Weird creatures living miles beneath the ocean waves could hold the key to finding extra-terrestrial life, say scientists.
They include huge red-tipped tube worms, ghostly fish, strange shrimp with eyes on their backs and other unique species.
A research vessel has set sail to look for them - shedding fresh light on how aliens may be all over the universe.
It was decked out with state-of-the-art equipment for the inaugural 40-day mission.
Falkor is sailing along the mid-Atlantic ridge, where the movement of tectonic plates creates tears in the seabed.
It will search for unusual kinds of hydrothermal vents – seabed fissures that emit geothermally heated water – and the strange forms of life they host.
Similar organisms could exist on watery moons and planets beyond the solar system.
The ship has about 30 types of oceanographic, navigational and atmospheric sensors.
There are also eight laboratories and accommodation for nearly 100 crew, reports New Scientist.
Expedition leader Dr. David Butterfield, of Washington University in Seattle, said: "When people think of hydrothermal vents, they often picture 'black smokers.'
"But the ones we're looking for are completely different and they're much harder to find because they don't release those billowing plumes of smoke."
Teams on board will use sonar to map out the terrain. Autonomous underwater vehicles (AUVs) - will search for chemical signatures from reactions between seawater and hot magma seeping up through the cracks.
Butterfield said: "The ocean is so poorly understood - we're on a mission to help change that."
Promising locations will be explored using a remotely operated robot called SuBastian - while watching on banks of screens on the ship.
SuBastian can reach nearly three miles down - deeper than the ocean.
High-resolution footage will be live-streamed so researchers and the public alike can see the first glimpses of any new creatures found near vents.
A phenomenon called serpentinisation occurs between the water and mantle rocks at vents - producing hydrogen, methane and other organic compounds.
This allows microbes to rely on chemosynthesis, using chemical energy to drive their metabolism.
It also enables animals that consume the microbes to live there even though no sunlight reaches them.
Expedtion member Dr. Julie Huber, of Woods Hole Oceanographic Institution in Massachusetts, said: "We're interested in how the chemistry, microbiology and resulting animal communities are linked to the geology of their habitat."
