The caves are nicknamed "Hell" for their 160-degree temperatures.

By Jess McHugh
February 25, 2017
Courtesy of Penelope Boston / New Mexico Tech

In a mysterious Mexican cave nicknamed “Hell” by scientists, a research team discovered ancient forms of life that may be up to 50,000-years-old.

The ancient microbes were unearthed inside a series of large crystals in the Naica caves in Chihuahua, northern Mexico, the Associated Press reported. Penny Boston, then the director of Cave and Karst Studies at New Mexico Tech and currently the director of NASA’s Astrobiology Institute, worked inside caves that ranged from approximately 500 feet deep to 2,600 feet deep.

The beauty of the crystals stands in stark contrast to the harsh conditions of the cave, assumed to be too hot to sustain life. Visitors to the caves have often described them as otherworldly, with jutting crystals of translucent white and purple. Two brothers first discovered the caves by accident in 2000 while drilling for lead and silver.

Mike Spilde / University of New Mexico

The temperature hovers around approximately 140 degrees Fahrenheit, Boston told Travel + Leisure. She and her team wore special suits covered in ice packs, along with ice packs under their helmets. They could only work in periods of 30 minutes followed by four hours of rest because of muscle exhaustion.

“It’s definitely a challenging environment,” she said.

Boston has been studying the microbes of these caves for the past nine years, seeking to understand what has allowed them to survive under such conditions. The some 40 strains of microbes and viruses are exceptionally unusual, with their closest known genetic relative being 10 percent different—about the difference between a human and a mushroom, according to AP.

“It shows that life can remain viable in a geological material for at least a number of tens of thousands of years,” she said, adding, “It’s a long story about how organisms, especially microbes, have learned to persist.”

Boston revealed her findings at a recent scientific conference, and her research has not yet been peer reviewed. She has plans to publish in a scientific journal and is still deciding which one.