Bruno Escribano of the Basque Center for Applied Mathematics and his colleagues say scientists know surprisingly little about brinicles, hollow tubes of ice that can grow several yards in length around streamers of cold seawater under polar pack ice.
Writing in a journal of the American Chemical Society, the researchers report brinicles are similar to a "chemical garden," a traditional demonstration in chemistry classes and children's chemistry sets in which tubes grow upward from metal salts dropped into silicate solution.
In the case of brinicles, the growth is in a downward direction into cold seawater.
Brinicles provide an environment that could well have fostered the emergence of life on Earth billions of years ago and could have done so on other worlds, meaning life may not necessarily have originated in warm tropical seas as generally believed, the researchers said.
"Beyond Earth, the brinicle formation mechanism may be important in the context of planets and moons with ice-covered oceans," they wrote in their journal article, citing in particular Ganymede and Callisto, two moons of Jupiter.