Tag Archives: saltwater

A Saltwater Pool in an Underwater Volcano: Habitat for Extraterrestrial Life Forms?

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Creatures uncovered near the Mabahismon volcano in the Red Sea, such as amphipods and polychaete worms

Dr. Katrin Linse

Ultra-salty lakes rich in carbon dioxide can support extreme life forms that differ from those found in other environments.

Dense saline water, laden with minerals, sinks to the ocean floor, where it can pool in depressions, creating unique brine lakes distinct from the upper waters. These brine pools, identified in various oceans, feature a unique chemical makeup—low in oxygen yet rich in particular minerals—allowing extreme microorganisms to thrive and evolve.

Recently, Froukje van der Zwan from King Abdullah University of Science and Technology in Saudi Arabia and her team have identified a novel brine pool that is warm, carbon-rich, and possibly nourished by underwater volcanic activity.

On a recent expedition to two underwater volcanoes in the Red Sea, Haty Bamons and Mabahismons, Van der Zwan and her colleagues found several brine pools located near the summit of the volcano, about five kilometers from mineral deposits where salt concentration increases. They also discovered regions with numerous hydrothermal vents releasing mineral-rich water at temperatures around 60°C (140°F).

Using a robotic vehicle for sampling revealed that the pool was warmer than the surrounding water and exhibited elevated levels of metallic elements like zinc and manganese.

The hot water vents also contained rich gas. “They show relatively high CO2 levels, similar to methane… however, unlike other hot water vents where liquids mix with seawater, this might function as a trap for these gases, being sequestered in the salt water here.”

Researchers are currently examining microbial samples collected from these pools to understand how life adapts to such extreme environments. Nearby hydrothermal vents revealed thick mats and diverse lifeforms, including polychaete worms and amphipods, featuring microorganisms considerably larger than known marine counterparts.

Living within a saline pool may offer insights into how life might thrive in harsh extraterrestrial environments, such as the salty, iron-rich oceans beneath the icy crust of Jupiter’s moon Europa. If hydrothermal activities exist beneath this surface, it could present scenarios similar to the iron-rich brine pool discovered by Van der Zwan and her research team.

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Source: www.newscientist.com

Titan, Saturn’s moon, boasts both freshwater rivers and saltwater oceans

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Titan’s north polar region, imaged using Cassini’s radar signature, shows blue hydrocarbon oceans.

NASA / JPL-Caltech / Italian Space Agency / USGS

The most detailed look yet at Saturn’s moon Titan’s strange lakes has revealed a diverse marine landscape similar to Earth’s, with a mix of freshwater rivers and saltwater oceans.

Unlike Earth’s watery oceans, Titan’s lakes are composed of methane and ethane, which are liquid at the planet’s average surface temperature, about −179 °C (−290 °F).

Radar measurements from NASA’s Cassini spacecraft, which orbited Saturn from 2004 to 2017, suggested differences in the lakes’ properties, including their composition and surface waves, but the signals didn’t contain enough information to distinguish between them.

now, Valerio Poggiali Poggiali and his colleagues at Cornell University in New York used a different radar technique to map the composition and surface of Titan’s oceans, revealing that the amount of ethane increases as you move south across the planet from the north pole. “The further north you go, the cleaner and purer the oceans become. They’re dominated by methane,” Poggiali says.

Previous radar measurements were made using signals sent and received at the same location on the Cassini spacecraft, which meant the reflected radio waves were polarized in one direction, or twisted.

The new study analyzed signals from Cassini’s radar that were reflected off the lake’s surface and picked up by NASA’s Deep Space Network, a radio antenna on Earth. The shallow angle of the reflected signal meant it contained two different polarized waves, giving Poggiali and his colleagues more information about the lake’s properties.

They found that many of the rivers and estuaries that feed the lake have rough surfaces caused by wind-driven waves, which could be a sign of active tides and currents feeding into the lake, Poggiali said. “Surface activity is very important if we want to plan future missions like a Titan submarine, but also to better understand Titan’s environment in terms of wind and atmospheric properties.”

Poggiali and his colleagues also found that the methane content was higher before the river flowed into the lake, which could help trace the methane and ethane cycle on Titan, Poggiali says. Ingo Muller-Wodarg “On Earth, when rivers flow into large, salty oceans, we find that the water becomes less saline near where the river flows in,” say researchers from Imperial College London. “Something similar is happening here, but it’s not the salinity that’s the problem, it’s the relative proportions of methane and ethane.”

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Source: www.newscientist.com