Scientists have discovered the deepest crack on the Earth’s crust on the Caribbean Sea floor, along with signs of life that at that those crushing depths could mean alien life could exist on other planets, NASA said.
A NASA-funded team discovered three hydrothermal vents - fissures in a planet's surface from which geothermally heated water comes – including one about 16,000 feet under the sea along a 100-kilometer (62-mile) stretch called the Mid-Cayman Rise. That stretch of sea bed is an ultra-slow spreading ridge that is part of the tectonic boundary between the North American and Caribbean plates.
Though these hydrothermal vents are far from sunlight and under the extreme pressures of the oceans, some of them get as hot as a convection oven, and scientists say they host bizarre communities that could lead to clues about how life may exist on other planets.
“Most life on Earth is sustained by food chains that begin with sunlight as their energy source. That’s not an option for possible life deep in the ocean of Jupiter’s icy moon Europa, prioritized by NASA for future exploration,” said Max Coleman, co-author of the study with NASA’s jet propulsion laboratory.
“However, organisms around the deep vents get energy from the chemicals in hydrothermal fluid, a scenario we think is similar to the seafloor of Europa, and this work will help us understand what we might find when we search for life there.”
The team’s findings were published in last week’s Proceedings of the National Academy of Sciences.
Chris German, the team’s chief scientist and a geochemist at Woods Hole Oceanographic Institute, said the team is trying to translate its findings to help plan for future space missions. There may be applications in the search for life on Mars and moons that have an icy ocean, he said.
Despite uncertainty surrounding NASA’s space program, which has only two Space Shuttle missions left and a dwindling budget, discoveries such as German’s may help show the need for future space exploration.
The newly discovered vent, named Piccard, is 2,600 feet deeper than the previously known deepest vent found in the Pacific Ocean in 1977.
Another newly discovered vent, Walsh, was found in rocks that are composed of material similar to the much hotter lavas that erupted on Earth’s very earliest seafloor thousands of years ago.
The third site, Europa, named after the icy Jupiter moon that scientists believe may contain life, is believed to be a unique shallow low-temperature vent that has only been reported once, at the “Lost City” site in the mid-Atlantic.
The team scoured for the vents using sensors on unmanned robotic vehicles programmed to track chemicals and microbes discharged from the vents.
Researchers said the mission marked the first time they were able to obtain microbial data from primitive organisms that thrive in high-temperatures and the lack of oxygen at this depth. German believes what his team has obtained so far is a fraction of the community of organisms that live on the chemical energy at the vents.
The team plans on returning to the vents to better examine the life there. German also said the team hopes to take the mission to the Arctic, where conditions are much more similar to those on other planets.