by Dave Bunnell » Mar 19, 2007 11:47 pm
If you check the units in the article, they have pits up to 252m wide, which is like, 827 feet! And a depth of 130m, or 426 feet. This far surpasses anything known in the way of a lava tube skylight on Earth. I think the largest puka known from Hawaii is maybe a couple hundred feet across, at best. Some of the big pit craters, which aren't skylights, can certainly attain these sizes. But the thermal data reported for pit "annie" suggests that these are more likely skylights connected to cave systems than pit craters, so all the more intriguing with their size.
This is sheer speculation, but it seems reasonable to me that a place with lower gravity might be able to sustain broader passage widths than our terrestrial caves, before collapsing under their own weight.
Clearly they will need a team of competent cavers on future manned expeditions. Could you see doing vertical work in a bulky space suit? And looks like a job for Willie Hunt's super flashes to photograph them...
Dave
NSS News Editor