February 25, 2011 - Today, ISRO, the Indian Space Research Organization, has released a paper detailing the discovery of a 1.72 kilometer long (5,733 ft.) intact lava tube section in the south western reaches of Oceanus Procellarum, the Ocean of Storms.
The data was compiled by Chandrayaan-1's Terrain Mapping Camera (TMC), one of the eleven science instruments on board India's first lunar orbiter, launched October 22, 2008.
"The TMC image is in the panchromatic spectral range of 0.5–0.75 μm with a stereo view in the fore, nadir and aft directions of the spacecraft movement and with a high spatial resolution of 5 m at an orbital height of 100 km (ref. 1), to enable three-dimensional viewing of the lunar surface with crisp and clear surface features and morphology.
"The Digital Elevation Model (DEM) generated from the three look angles enables morphometric study of various lunar features, thus furnishing topographic relief and dimensions of various morphological entities.
"Identifying sites for permanent base stations for possible human settlement on the Moon is important for long-term perspective of lunar exploration."
Japan's Kaguya probe had previously discovered the first of several lavatube "skylights" now known, the find announced in 2009.
The Chandrayaan-1 finding reinforces the prevailing assumption that the basaltic lava flow areas of the Moon (the maria, pronounced MAH-ria, Latin for seas) that occupy 39% of the Moon's nearside, and a lesser portion of the Farside.
These are substantial and voluminous spaces well-shielded from the cosmic elements of radiation and micrometeorites, and as such provide ideal locations for area-intensive developments such as warehousing, industrial parks, agriculture, archiving, and settlements.
We have dubbed them "the Moon's Hidden Valleys." Public perception of the Moon is of a barren rock-strewn rubble pile. But this perception is superficial.
Lavatube Skylight Explorer: Building on the previous discovery of lavatube skylights on the Moon, the Society has announced its intention to sponsor an engineering competition to design a probe that could lower itself down into one of these skylights and explore what it sees. You will find our Lavatube Explorer powerpoint presentation on this competition here.
Read this collection of articles on Lunar Lava Tubes published in Moon Miners' Manifesto over the years.
A discovery long predicted: More than two decades ago, Cassandra Coombs and B. Ray Hawke had published a list of such "interruptions" in various lunar rilles, suggesting that they represented "uncollapsed" sections of an original long lava tube. It was the Apollo 15 mission, which,ack in the summer of 1971, set down along the rim of Hadley Rille, that convinced lunar geologists (selenologists is the correct, but out-of-favor term) that these features were the remains of collapsed lava tubes of gigantic proportions.
Perhaps the most familiar of these suspected "interrupted" rille sections are those along Hyginus Rille in central nearside. (See the slide in the LavatubeExplorer presentation mentioned above.)
What has been needed is a very high resolution view taken from just the right angle facing one/both "end(s)" of such an "interruption" or "bridge" and that is what Chandrayaan-1's high-resolution Terrain Mapping Camera has provided. We look forward to the release of similar findings elsewhere on the Moon.
It is a top level priority of the Moon Society to change public perception of the Moon from that of a "been there, done that rubble pile" to one of "a fascinating world of Hidden Valleys ideal for human settlement and begging to be explored." The purpose of our Lavatube Skylight Explorer engineering competition is to motivate NASA or some other space agency to begin exploring these hidden bu promising features. We do this in the tradition of the Lunar Prospector grass roots effort which ultimately resulted in the NASA mission of this name. As advocates, we cannot launch missions. But we can pave the way for"those who can" to see the importance of doing so.
We are encouraged that while NASA seems to have turned its back on the Moon, to go with the flow to Mars, the space agencies of other nations have not done so. The International approach, with or without NASA, is more likely to "go the course" and prepare the way for the establishment of a permanent human pioneer frontier on this "Eight Continent."