Month: July 2024

Enlarge / The Fremen on Arrakis wear full-body "stillsuits" that recycle absorbed sweat and urine into potable water. (credit: Warner Bros.)

The Fremen who inhabit the harsh desert world of Arrakis in Frank Herbert's Dune must rely on full-body "stillsuits" for their survival, which recycle absorbed sweat and urine into potable water. Now science fiction is on the verge of becoming science fact: Researchers from Cornell University have designed a prototype stillsuit for astronauts that will recycle their urine into potable water during spacewalks, according to a new paper published in the journal Frontiers in Space Technologies.

Herbert provided specific details about the stillsuit's design when planetologist Liet Kynes explained the technology to Duke Leto Atreides I:

It's basically a micro-sandwich—a high-efficiency filter and heat-exchange system. The skin-contact layer's porous. Perspiration passes through it, having cooled the body ... near-normal evaporation process. The next two layers ... include heat exchange filaments and salt precipitators. Salt's reclaimed. Motions of the body, especially breathing and some osmotic action provide the pumping force. Reclaimed water circulates to catchpockets from which you draw it through this tube in the clip at your neck... Urine and feces are processed in the thigh pads. In the open desert, you wear this filter across your face, this tube in the nostrils with these plugs to ensure a tight fit. Breathe in through the mouth filter, out through the nose tube. With a Fremen suit in good working order, you won't lose more than a thimbleful of moisture a day...

The Illustrated Dune Encyclopedia interpreted the stillsuit as something akin to a hazmat suit, without the full face covering. In David Lynch's 1984 film, Dune, the stillsuits were organic and very form-fitting compared to the book description, almost like a second skin. The stillsuits in Denis Villeneuve's most recent film adaptations (Dune Part 1 and Part 2) tried to hew more closely to the source material, with "micro-sandwiches" of acrylic fibers and porous cottons and embedded tubes for better flexibility.

Enlarge / The intrepid three-legged lion Jacob and his brother Tibu prepare for a hunt. (credit: Alexander Braczkowski)

On February 4, scientists monitoring lion populations in Uganda captured nighttime thermal drone footage of two lions—brothers dubbed Jacob and Tibu by the Uganda Wildlife Authority—swimming across the predator-infested Kazinga Channel connecting two lakes, most likely to find mates. While there have been prior reports of lions swimming short distances, Jacob and Tibu covered about 1.5 kilometers (nearly one mile)—the longest swim yet recorded, according to a new paper published in the journal Ecology and Evolution.

"The fact that [Jacob] and his brother Tibu have managed to survive as long as they have in a national park that has experienced significant human pressures and high poaching rates is a feat in itself—our science has shown this population has nearly halved in just five years," said co-author Alexander Braczkowski of Griffith University, who has been working with the government of Uganda since 2017 to monitor the lion population in the area. "His swim, across a channel filled with high densities of hippos and crocodiles, is a record-breaker and is a truly amazing show of resilience in the face of such risk.”

Jacob and Tibu's impressive feat is likely the result of increased pressure from human encroachment, according to Braczkowski. He co-authored a 2020 paper proposing a novel census technique that could be used more broadly as an early warning of lion declines. Their method revealed a worrying movement parameter for both male and female lions in Uganda's Queen Elizabeth National Park, where the home range increased to 3.27 km (a 400 percent increase) for males and 2.22 km (a 100 percent increase) for females—likely a response to systematic prey depletion due to poaching, for example. And the sex ratio was dangerously skewed: one male to 0.75 females, a highly unusual occurrence.