Solving the Mystery of Blood Falls

Originally attributed to red algae, a new study unveiled origins much truer to its cryptic namesake.

With a name ripped straight from classic horror or sci-fi canon, Antarctica’s Blood Falls has been somewhat of a mystery since its discovery over a century ago.

Housed on the 62-mile long Taylor Glacier, this area is infamous for the blood-red liquid oozing from beneath it. Originally attributed to red algae from an assumed underground lake, last week a study unveiled origins much truer to its cryptic namesake.

To better understand the composition of Blood Falls, scientists used radio-echo sounding technology, which is similar to the echolocation used by bats, to map out a grid of what lies beneath the glacier. They discovered tributaries from a sea of saltwater.

Saltwater melts at lower temperatures, and actually releases heat as it freezes. This allows it stay liquid despite temperatures that go as low as 1.4 degrees Fahrenheit on the glacier. At the same time, a lack of oxygen means this saltwater forms a type of brine with twice the normal salt content.

This brine is injected with tremendous pressure through a network of crevasses that run longer than three football fields until pushing through at Blood Falls. As this iron-rich saltwater hits the air, it turns red.

So really, it should be called Rust Falls, but that’s already been snapped up by Texas.

Additionally, researchers discovered that much of this iron is absorbed by bacteria living within the brine, as water samples from Blood Falls contained at least 17 different types of microbes.

Trapped beneath the glacier with no light and limited oxygen, the bacteria recycle their sulphate supply, reducing it to sulphite – which would react with the high iron content of the water, and producing more sulphate to consume.

Scientists think that this adaptation could offer an initial example of long-term life surviving under extreme conditions. The prospect of organisms that can survive in this type of environment could also offer insight on life in dark, frozen, and airless environments like Mars.

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