Lunar lava tube
Encyclopedia
Lunar lava tubes are sub-surface tunnels on the Moon
that are believed to have formed during basaltic lava flows. When the surface of a lava tube
cools, it forms a hardened lid that contains the ongoing lava
flow beneath the surface in a conduit-shaped passage. Once the flow of lava diminishes, the tunnel may become drained, forming a hollow void. Lunar lava tubes are formed on surfaces that have a slope that ranges in angle from 0.4–6.5°. Lunar lava tubes may be as wide as 500 metres (1,640.4 ft) before they become unstable against gravitational collapse. However, stable tubes may still be disrupted by seismic events or meteoroid bombardment.
One such area containing lava tubes and rilles is the Marius Hills region. In 2008, an opening to such a lava tube in this area may have been discovered by the Japanese Kaguya
spacecraft. The Hadley Rille
may have been a partly roofed lava channel, some parts of which have since collapsed. There may also be lava tubes in the Mare Serenitatis
.
Lunar lava tubes may potentially serve a role as enclosures for manned habitats. Tunnels larger than 300 metres (984.3 ft) in diameter may exist, lying under 40 metres (131.2 ft) or more of basalt with a stable temperature of -20 C. These natural tunnels provide protection from cosmic ray
radiation, meteorite
s, micrometeorites, and ejecta from impacts. They are shielded from the variations in temperature at the lunar surface, which would provide a stable environment for inhabitants. Lunar lava tubes are typically found along the boundaries between lunar mares and highland regions. This would give ready access to elevated regions for communications, basaltic plains for landing sites and regolith
harvesting, as well as underground mineral resources.
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
that are believed to have formed during basaltic lava flows. When the surface of a lava tube
Lava tube
Lava tubes are natural conduits through which lava travels beneath the surface of a lava flow, expelled by a volcano during an eruption. They can be actively draining lava from a source, or can be extinct, meaning the lava flow has ceased and the rock has cooled and left a long, cave-like...
cools, it forms a hardened lid that contains the ongoing lava
Lava
Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...
flow beneath the surface in a conduit-shaped passage. Once the flow of lava diminishes, the tunnel may become drained, forming a hollow void. Lunar lava tubes are formed on surfaces that have a slope that ranges in angle from 0.4–6.5°. Lunar lava tubes may be as wide as 500 metres (1,640.4 ft) before they become unstable against gravitational collapse. However, stable tubes may still be disrupted by seismic events or meteoroid bombardment.
One such area containing lava tubes and rilles is the Marius Hills region. In 2008, an opening to such a lava tube in this area may have been discovered by the Japanese Kaguya
Kaguya
Kaguya was a mouse that had two parents of the same sex . She was named after a Japanese folk tale, in which the moon-born princess Kaguya is found as a baby inside a bamboo stalk.-The process of "parthenogenesis":...
spacecraft. The Hadley Rille
Mons Hadley
Mons Hadley is a massif in the northern portion of the Montes Apenninus, a range in the northern hemisphere of the Moon. The selenographic coordinates of this peak are 26.5° N, 4.7° E. It has a height of 4.6 km and a maximum diameter of 25 km at the base.To the southwest of this mountain...
may have been a partly roofed lava channel, some parts of which have since collapsed. There may also be lava tubes in the Mare Serenitatis
Mare Serenitatis
Mare Serenitatis is a lunar mare that sits just to the east of Mare Imbrium on the Moon.It is located within the Serenitatis basin, which is of the Nectarian epoch. The material surrounding the mare is of the Lower Imbrian epoch, while the mare material is of the Upper Imbrian epoch...
.
Lunar lava tubes may potentially serve a role as enclosures for manned habitats. Tunnels larger than 300 metres (984.3 ft) in diameter may exist, lying under 40 metres (131.2 ft) or more of basalt with a stable temperature of -20 C. These natural tunnels provide protection from cosmic ray
Cosmic ray
Cosmic rays are energetic charged subatomic particles, originating from outer space. They may produce secondary particles that penetrate the Earth's atmosphere and surface. The term ray is historical as cosmic rays were thought to be electromagnetic radiation...
radiation, meteorite
Meteorite
A meteorite is a natural object originating in outer space that survives impact with the Earth's surface. Meteorites can be big or small. Most meteorites derive from small astronomical objects called meteoroids, but they are also sometimes produced by impacts of asteroids...
s, micrometeorites, and ejecta from impacts. They are shielded from the variations in temperature at the lunar surface, which would provide a stable environment for inhabitants. Lunar lava tubes are typically found along the boundaries between lunar mares and highland regions. This would give ready access to elevated regions for communications, basaltic plains for landing sites and regolith
Regolith
Regolith is a layer of loose, heterogeneous material covering solid rock. It includes dust, soil, broken rock, and other related materials and is present on Earth, the Moon, some asteroids, and other terrestrial planets and moons.-Etymology:...
harvesting, as well as underground mineral resources.