Moon's Huge Lava Tubes Perfect For Heinlein's Bat Wings

Lava tubes on Earth, in California, Hawaii and Iceland, result when underground rivers of molten rock empty out, leaving channels up to 30 meters across. Planetary geophysicist Dave Blair of Purdue University in West Lafayette, Indiana and colleagues estimate that lunar caves could exist that are up to 5 kilometers across!


(Thurston Lava Tube, Hawaii)

Mounting evidence from the SELENE, LRO, and GRAIL spacecraft suggests the presence of vacant lava tubes under the surface of the Moon. GRAIL evidence, in particular, suggests that some may be more than a kilometer in width. Such large sublunarean structures would be of great benefit to future human exploration of the Moon, providing shelter from the harsh environment at the surfaceóbut could empty lava tubes of this size be stable under lunar conditions? And what is the largest size at which they could remain structurally sound?

We address these questions by creating elasto-plastic finite element models of lava tubes using the Abaqus modeling software and examining where there is local material failure in the tube's roof. We assess the strength of the rock body using the Geological Strength Index method with values appropriate to the Moon, assign it a basaltic density derived from a modern re-analysis of lunar samples, and assume a 3:1 width-to-height ratio for the lava tube. Our results show that the stability of a lava tube depends on its width, its roof thickness, and whether the rock comprising the structure begins in a lithostatic or Poisson stress state.

With a roof two meters thick, lava tubes a kilometer or more in width can remain stable, supporting inferences from GRAIL observations. The theoretical maximum size of a lunar lava tube depends on a variety of factors, but given sufficient burial depth (500 m) and an initial lithostatic stress state, our results show that lava tubes up to five kilometers wide may be able to remain structurally stable.

Fans of science fiction Grandmaster Robert A. Heinlein find themselves nodding sagely, since reading all about such structures in his 1957 novel Menace from Earth:

Most of the stuff written about Bats' Cave gives a wrong impression. It's the air storage tank for the city, just like all the colonies have - the place where the scavenger pumps, deep down, deliver the air until it's needed. We just happen to be lucky enough to have one big enough to fly in. But it never was built, or anything like that; it's just a big volcanic bubble, two miles across, and if it had broken through, way back when, it would have been a crater.

Never one to neglect the adventuresome spirit of American youth, Heinlein obligingly provided lunar colonists with Storer-Gulls Wings for recreational use of lunar lava tubes.

Via The structural stability of lunar lava tubes.

Scroll down for more stories in the same category. (Story submitted 12/15/2016)

Follow this kind of news @Technovelgy.

| Email | RSS | Blog It | Stumble | del.icio.us | Digg | Reddit |

Would you like to contribute a story tip? It's easy:
Get the URL of the story, and the related sf author, and add it here.

Comment/Join discussion ( 0 )

Related News Stories - (" Space Tech ")

Miners! NASA Wants To License RASSOR Excavator
'The borers had been dismantled and packed away.' - Ray Cummings, 1930.

Starshade Will Help Space Telescope To Search For Exoplanets
'When it found planetary systems in its field, automatically shifted upon them a higher powered telespectroscope ...' - Edmond Hamilton, 1936.

Yes, But Do Astrobees Have Lasers For Lightsaber Training?
'... Ancient weapons are no match for a good blaster at your side, kid.' - George Lucas, 1977.

Japan Uses Explosives On Asteroid
'...a tiny, rocket-powered projectile, drove towards the mysterious bulk. It hit, exploding into a cloud of incandescent vapour.' - EC Tubb, 1958.

 

Google
  Web TechNovelgy.com   

Technovelgy (that's tech-novel-gee!) is devoted to the creative science inventions and ideas of sf authors. Look for the Invention Category that interests you, the Glossary, the Invention Timeline, or see what's New.

 

 

 

 

 

Current News

Miners! NASA Wants To License RASSOR Excavator
'The borers had been dismantled and packed away.'

Bee+ Robobee Now With Four Wings
'It was a tiny thing, scarcely more than an inch and a half in length...'

CNSILK Robotic Spider Builder
'We could certainly spin a web right through the Solar System, if we can think of a good use for one.'

Starshade Will Help Space Telescope To Search For Exoplanets
'When it found planetary systems in its field, automatically shifted upon them a higher powered telespectroscope ...'

Tiny LEDs Developed For Dust-Sized Computers
'They use sparkles to talk to each other...'

Is There Extraterrestrial Life Here In The Solar System
'How fast is it moving? ...one meter per minute.'

Can We Comprehend Deep Learning Systems?
'Youíve nothing remotely like it, so I canít describe it to you.'

Skin Electronics Can Show Electrocardiogram
'... the young men in the streets who applied polyimde OLED body film to their bared shoulders.'

Chinese Fern Helps Remediate Arsenic Soil
'Bioengeering had put out a spec report on the long crawly things five months back.'

Skai Air Taxi Costs The Same As Uber
'The air-taxi found its way past and around other ground-cars...'

Neurodevices For Consumers? Neuroethicists (And Philip K Dick) Say 'Caveat Emptor'
'They tried to use it today and it wouldn't work. No colors and no ceph patterns, neither one...'

NASA 3D Printed Habitat Challenge Won By AI SpaceFactory
3D printing - on Mars!

The Future Of Elon Musk's Neuralink
'Cerebral Electromagnetic Emmission Amplification and Relay System ó call it artificial telepathy, if you like.'

Researchers Make You Say Anything in Videos
'[It] caused his televised image... to mouth the vowels and consonants beautifully.'

Jeff Bezos Tries Waldoes (Robotic Hands)
'Waldo put his arms into the primary pair before him...'

Asimov and Musk - Boring Company Tunnel vs. Street Race
'There was almost no sound, just a steady velvety whirr as the taxi sped along.'

More SF in the News Stories

More Beyond Technovelgy science news stories

Home | Glossary | Invention Timeline | Category | New | Contact Us | FAQ | Advertise |
Technovelgy.com - where science meets fiction™

Copyright© Technovelgy LLC; all rights reserved.