Science 360 s picture of the day is a stunner: Blood Falls, a discharge of deep red water off the edge of Taylor glacier in Antarctica.

In the image above, that little beach ball-appearing object on the bottom left is actually a researcher’s tent, giving you a sense of the massive size of the feature.

“Scientists believe a buried saltwater reservoir is partly responsible for the discoloration [in the falls], which is a form of reduced iron,” Science 360 says.

Researchers at Ohio State University concluded the underground lake feeding the falls formed about 5 million years ago when sea levels were higher and the ocean extended deeper into the Antarctic continent.

“This five-story, blood-red “waterfall” pours ever so slowly out of the Taylor Glacier in Antarctica’s McMurdo Dry Valley,” notes Slate whose Atlas Obscura Web site features a remarkable gallery of images.

For more on Blood Falls, check out The Weather Channel’s feature: Blood Falls: Antarctica’s Stunning Secret (PHOTOS) and EarthSky’s piece: Blood Falls, five stories high, seeps from an Antarctic glacier