06.015 Lava tubes on the Moon could provide space for whole cities

derStandard.at
Lava tubes on the Moon could provide space for whole cities, 29.08.2020

Science > Space > Manned space travel

Space colonies

Lava tubes on the Moon could provide space for whole cities

Italian researchers see great potential in Lunar and Martian tubes

29. August 2020

Lavaroehre

Cave researchers reconnoitre one of the easier accessible lave tubes (because situated on earth). Their substantial larger counter parts on Moon and Mars could become important for future colonizing projects.

The caverns, towards which also the space visionaries from science have directed their attention already longer, are lava tubes. It is natural architecture, which builds itself: When with a volcanic eruption thin flowing lave flows down a slope with low gradient, it sets at the cool rims, while it goes on flowing in the interior. So a closed tube is formed, which in the end remains as cavity, when the last rest of lava has flown through.

Protection in the tube.

One knows such tubes from some volcanic active regions on earth very well. But for space travel of the future it is relevant, that they are also on the Moon and on Mars: therefore those two heavenly bodies, which are still wishful aim 1 and 2 of an interplanetary colonizing. And on the basis of the small gravity, the lunar and martian lava tubes are by something larger than the earthly - what could make them usable.

What makes these cavities to attractive, is their protective function. Not enough with it, that one is exposed to the vacuum on the surface of the Moon, this vacuum is unfortunately also everything else than empty: In addition to the omnipresent shower of high energetic particles of the cosmic radiation, also micro meteorites can still come, which would smash every protective suit. In the lava tubes colonists would be immune from such microscopic, but still deadly dangers. Moreover the day and night temperatures in the tube interior would not fluctuate so much as on the surface. Infrastructure would therefore be built up there by something easier (at least as soon as one first of all has found an access to the caves).

Earthly conditions as starting point

In autumn 2019 the European Space Agency ESA directed an appeal to universities and research enterprises, to work out ideas for the reconnaissance of the cave systems on the Moon. The speleologist Francesco Sauro of the University Bologna and the geologist Riccardo Pozzobon of the University Padua belong to those, who have followed the appeal. They drew up an assessment, whether extra-terrestrial lave tubes would be a rewarding aim at all. The results were published in the specialist journal "Earth-Science Reviews".

First the researchers attended to lava tube systems on earth, for example in Australia, but above all on volcanic islands like Iceland, Hawaii, the Canaries or the Galapagos Islands. Sizes and morphology of the systems were of interest then and quite particularly the so-called skylights. That are places, where the tube roof has collapsed and grants access to the system. Moreover the researchers measured the ratio of collapsed tubes to the total size of the respective system.

Related structures

These data they compared with such about the surfaces of Moon and Mars, which came from satellites and probes. Stereoscopic pictures, gravimetric measures and radar investigations showed for example in the Marius Hills in the Oceanus Procellarum of the Moon hollow spaces and places run in a straight line, where such caves are collapsed. All in all the examined formations would strongly be similar to those, which are known on Earth.

They are just clearly larger. Their diameter does not lie on average ten to 30 metre as on Earth, but is 100 to 1,000 times larger. The lower gravity had here a double effect: First on the volcanism, which has created the tubes. And after that on its static - despite their gigantic dimensions they clearly remain within the area of stability according to the researchers. There, where collapses actually happened, larger meteorites may have smashed in. Future space travellers could easily descend through these skylights into the cave system fairly comfortably.

Loads of space

Pozzobon notes with view on his university city, that one could put up the whole city centre of Padua in the bulky tubes (which is size wise comparably with Linz by the way). In comparison even the splendid Moon cities from McDonald's "Luna" novels would then even fade.

The way there is though still far. Although the usability of lava tubes on Moon and Mars is since then discussed in the planet research for decades, equipment and manpower is lacking till now, to start an actual reconnaissance. All international space agencies added up, up to now all of 36 astronauts have received training in cave climbing according to Sauro and Pozzobon; ten are trained in practical geological field research. There is still space upwards, for the Italian researchers think the cave systems of the Moon to be an above all measure awarding aim for reconnaissance and a possible settlement. (jdo, 29.8.2020)

Previous webpage: 06.014 Next webpage: 07

Start: To the start of this webpage.

[Home]>[Miscellaneous]>[7. The Solar System]>[06. Moon]>[06.015 Lava tubes on the Moon could provide space for whole cities]

[Home] [How to Measure Your Beliefs] [The Man-Made Church] [Miscellaneous]

The address of this webpage is:
http://www.fpreuss.com/en3/en02/en0206/en0206015.htm