THE LUMINOUS FISH EFFECT: SHELDON IS WRONG ABOUT CAVES

In “The Luminous Fish Effect,” Season 1, Episode 4, Sheldon is so very wrong about caves.

“Beneath southern China’s landscape of cone-shaped peaks, arches, and spires, researchers have discovered some of the largest underground chambers in the world. In 2013 a British-led expedition used a cutting-edge laser scanner to measure several cave systems in unprecedented detail, including Gebihe, whose Miao Room, with a maximum height of 627 feet, ranks as the world’s second largest known chamber. . . . It covers 1.27 million square feet (the equivalent of 22 football fields). . . . A giant stalagmite—at 148 feet tall, one of the largest in the world—dominates the open space under the massive dome at the end of the Miao Room.”

—National Geographic, “China’s Supercaves,” September 2014

“The Australian Aboriginal cave paintings, from this period, are the first hints of religion that humans have as proof of religious behavior. The caves in which the paintings are found date to 50,000 years ago through forensic geology and carbon dating. Most of the images found in their religious stories and ceremonies are depicted in these caves. We also have confirmation from the aborigines themselves that these images are their religious images. These paintings also are likely to be significant evidence for linking the use of Amanita Muscaria [commonly known as the fly agaric mushroom] to its use 50,000 years ago. This is because 50,000 years ago was when humanity entered Australia and also because Amanita Muscaria produces religious like experiences.”

—Leviak B. Kelly, Religion: The Ultimate STD (2014)

The Indiana Jones of Caving

British cave explorer Andy Eavis is often said to have discovered more underground territory than any other soul alive today. At the last count, 330 miles of new cave passages have submitted their secrets to Eavis. Now chairman of the British Caving Association, Eavis first visited the supercaves of China in 1982. But he returned in 2013, wanting to see more of our planet’s greatest concentration of the alien topography called karst: forested spires and sinkholes, stone towers and disappearing rivers, which form over millennia as rainwater erodes the soluble bedrock of limestone.

For hidden beneath the green iconic mountains of the cloistered Chinese country landscape is reflected a similar subterranean geography—the world’s biggest bunch of undocumented caves. Eavis spent a month in 2013 in at least three of the biggest chambers in the world, using $100,000 worth of 3D laser technology to map and measure them accurately for the very first time.

Imagine yourself inside such a gargantuan chamber, this cavernous wonderworld that Sheldon has declared forever uninteresting. Crouched on the floor, you hear nothing but your breathing and the faint, echoing drip of distant water. You see nothing but void, but when you turn to the screen of a laptop linked to a laser scanner, the huge chamber reveals itself. You virtually float up to its roof, which forms a cathedral arch 950 feet above the floor. You hover over a lake and finally touch down on a beach on the far side.

It’s the south of China that boasts the world’s largest cluster of eroded topographic karst. For over six hundred million years, the region was submerged under seas and amassed miles-deep layers of sediments. Geological uplift and erosion over time then helped create the massive caverns of today. The China Caves became famous when more than 160,000 tourists a year visited the nearby Dashiwei Tiankeng, a 2,000-foot-wide, 2,000-foot-deep sinkhole first known to karst geologists in 1998. But why do scientists study such fascinating caves, and what possible use could they be for our future?

Caves in Space

It’s little wonder earthlings spend so much time in caves, no matter what Sheldon says. For caves are also a crucial way to help us colonize space. For example, our moon has been a target of human colonization for many decades. It’s on our cosmic doorstep, within easy reach of our home planet. Missions such as NASA’s Apollo program put a total of twelve humans on the moon but also crucially tested the real challenges of lunar living. Each mission was made longer than the last, to explore the moon further and to test astronaut endurance while conducting various kinds of experiments. The Apollo program also taught humans how to transport large items of equipment and materials off-world.

And yet, during the long-term development of a colony on our moon, cave dwelling may well be the tactic humans adopt. Briefly visiting the moon is one thing, but living there is quite another. Conditions are harsh with huge temperature swings, from 134°C (273°F) at noon to -170°C (-274°F) at night. The lunar surface is ceaselessly blasted by micrometeorites and harmful cosmic rays. To survive this bombardment and radiation, human colonists might have to live underground in lunar “lava tubes,” subterranean tunnels on the moon formed by the flow of magma in the ancient past. When the exterior surface of a live lava tube cooled, it formed a hardened lid that trapped the ongoing lava flow under the lunar surface, in tunnel-shaped passages. Once the flow of lava died down, the tunnels drained, forming hollow catacombs.

For prospective colonists, these lava tubes are a very useful living space. Many are long, natural caves, as wide as five hundred meters (1,600 foot) before they become prone to gravitational collapse. Even if the tubes survive, shifting seismic events or meteoroid bombardment may still disrupt stable passages. You can imagine colonists in the future, spending many a nervous night, anxious about the strange, creaking noises coming from the lunar catacombs in the dark.

Colonists would dwell in the caves until more sophisticated living conditions could be built. The availability of food and water is a major challenge for moon colonization. At first, food would need to be brought along, and a lot more food than just the odd cheeseburger. Special machines would be needed to extract the water hidden in the soil at the southern lunar pole. Growing plants would be difficult, as the nights are cold and long and the daylight bright and harsh, as there is no atmosphere on the moon to reduce and scatter the sun’s radiation. And no lunar insects exist to pollinate the flowers, so an entirely new way of growing food would need to be found: little wonder the caves would feel like home and sanctuary!

Making Like Martians

The caves of the moon would act as just the first stepping-stone into outer space. Martian caves would be the second. It’s often said scientists know more about Mars than any planet other than Earth. That’s because Mars is the closest planet whose surface we can see through our telescopes. Our other near neighbor, Venus, is shrouded in a veil of mysterious cloud, but Mars is plain to see. Like Earth, Mars has a twenty-four-hour day, seasons, and polar caps. If there’s a planet that humans would colonize first, it would be Mars.

Mars has such huge potential that some futurists prefer to skip the caves of the moon and head straight for Mars. Of course, Mars also differs greatly from Earth. It lacks warm temperatures and liquid water. And a future Martian colony would face huge undertakings, such as fighting against global dust storms, mediating the harmful solar radiation, and melting the Martian polar ice into a sea twelve meters deep, covering much of the planet. How would human pioneers go about transforming Mars and meeting these crucial challenges? Caves!

NASA’s Mars Odyssey spacecraft made a stunning discovery in 2007. Odyssey spied entrances to possible caves on the slopes of a Martian volcano. The existence of a lava tube is sometimes revealed by the presence of such telltale “skylights,” a place in which the roof of the tube has collapsed, leaving a circular hole in the surface. This find fueled interest in potential underground habitats and sparked searches for caverns elsewhere on the Red Planet.

Mars has huge volcanoes, bigger than those on Earth. For example, the famous Martian volcano Olympus Mons reaches the impressive height of twenty-one kilometers, while the whole region of the Tharsis volcanic bulge covers a surface of over twenty-five million square kilometers. As gravity on Mars is about 38 percent of Earth’s, Martian lava tubes are expected to be much larger in comparison, and perfect for human habitation until the Martian colony can truly take off.

Mars would be the first human home away from home. The first launch could carry an unmanned Earth Return Vehicle (ERV) to Mars. The ERV could contain a nuclear reactor, which could power a unit to make fuel, using material found in the Martian atmosphere. Two years later, a manned mission could touch down near the ERV. The crew could stay for eighteen months, exploring the planet until returning to Earth using ERV-made fuel. The crew could be replaced by another team, and a string of bases could be set up.

The Martian lava tubes would act as a main base. The tubes may contain trapped water essential for life and may house reservoirs of ancient ice, since cool air can pool in lava tubes and help temperatures remain stable. The ability to tap into these reservoirs may provide dramatic insight into the history of possible life on Mars. Using the caves as a temporary home, in good time Mars will be terraformed. After several decades, the Red Planet will look as blue and watery as Earth. The hope is that, within a century, Mars could be terraformed into an oxygen-rich environment, supporting a human colony, some of whom may dream of traveling to the remote corners of the solar system, and beyond.

Now Sheldon, what was that again: there’s nothing interesting about caves?