lava tubes

The moon may be a harsh mistress, but lately she has been giving up her secrets. Scientists have spotted a deep hole in the lunar surface that goes at least 260 feet down and is believed to open into an underground tunnel more than 1,200 feet wide.

The discovery is powerful evidence for long, winding tunnels carved by lava beneath the lunar surface. Such tunnels, whose existence has long been hypothesized, could provide shelter for future astronauts or colonists against the harsh radiation and surface temperatures on the moon.

Hollowed-out mountains are good for so many things. They can house strategic military bases. They can store toxic waste. And if youre truly evil, you have the option of carving it into the shape of a skull, making it your secret headquarters, or periodically host kung-fu tournaments there. Or, you know, all three.

The Norwegians are hoping to use their hollowed-out mountains for the altruistic, though ominously named, Doomsday Vault. The vault will be a depository of seeds of all the known varieties of the worlds crops, just in case anything goes down. NASA, on the other hand, recently announced that they'll be upping the speed on the whole hollowed-out-mountain game by harnessing the naturally occurring hollow lava tubes on the moon as a library. Information could be stored on computers housed in these lava tubes and sent by satellite. At least its good to know that if one day NORAD happens to unleash its missiles or a kung-fu tournament on Skull Island goes horribly awry, all our seeds and back issues of PopSci will be safe.

What would you do with a hollowed-out mountain? Let us know in the comments section below. Me, Id make a gigantic bounce house. And host a kung-fu tournament. —Dan Smith

While vacationing in Hawaii, I enjoyed seeing the spouting horn on Kauai. Would you tell me how this natural wonder came to exist?


Thomas Rosendahl
Westchester, Calif.

If you've stood on the natural ledge of black lava at Lawai Beach in Koloa in the southern portion of the island of Kauai, watching as waves crash against the rocks, are channeled underground, and finally spewed upward, you've seen a natural phenomenon that comes courtesy of ancient volcanic activity.