Defeating the Radiation Danger?

There are many problems to be overcome if humans are to spread throughout the Solar System beginning yet this century. Likely, some problems we will encounter we don't even know about today. That is the way of frontiers. One problem we do know about is posed by radiation-- mostly coming from the Sun, but also cosmic radiation.



Radiation is not a showstopper on Earth or in low Earth orbut courtesy of Earth's powerful magnetic field, which forms a sort of coccoon around our planet that deflects harmful radiation. Once we fly out of that coccoon, however, we must find other ways to deal with radiation. The Moon is beyond that coccoon.



The Apollo kunar flights were short enough that the dangers of radiation exposure to the crews were deemed acceptable, and indeed, most of those men have gone on to lead long, seemingly healthy lives. Longer stays on the Moon, however, will demand some protection against radiation. Lunar lava tubes could be a big part of the answer.



Lava tubes are what the words suggest-- tubes of rock hollowed out by flowing lava long ago. The early Hawaiians sometimes used lava tubes for shelter. In the Moon's low gravity, lava tubes can be huge-- perhaps thousands of feet across and miles long. Such a tube could easily host a lunar base constructed of inflatable modules hauled from their landing site into the tube, for example. Power lines running from the base inside to a solar array outside could supply the base with energy.



The rock roof and sides of the tube would provide the base with good protection from radiation. Excursions by astronauts outside the tube would still need to be monitored with radiation exposure in mind, but spending much of their time in a protected haven should greatly lessen the danger.



Lava tubes no doubt exist on Mars as well. The Martian magnetic field is too weak to protect the suface from radiation, so using Martian lava tubes may work, too. Because the gravity on Mars is more than twice Lunar gravity, any tubes there may be smaller, but possibly big enough to protect a small base.



Building the future by essentially going back to living in caves may seem counterintuitive, but it also might be the safest, most efficient way to establish ourselves on other worlds.