SETTLING OFF EARTH
- transitioning to an ever expanding settlement -

WHICH DESTINATION
Will the first settlement be in Earth orbit, the Moon, Mars or somewhere else?

There are two primary factors competing with one another as to whether settlement will occur on the Moon versus Mars. The Moon's proximity to Earth strongly favors numerous round trips from Earth each year unlike Mars' round trips of 26 months. This will also affect the cost and inconvenience of traveling to the Moon.

However, Mars has the primary favorable factor in that its resources are a lot more accessible than that on the Moon. For this reason, Mars can greatly reduce its cargo costs compared to Mars. Also, SpaceX is especially comitted to Mars in the near-term and so one has to factor that into the considerations.

But, being able to remain in interactive, video communications with loved ones on Earth likewise strongly favors the Moon over Mars for older settlers who want to maintain convenient contact with family, friends, and colleagues.

WHERE ON MARS?
Arcadia Planitia has been identified as a location that SpaceX is looking at for their Initial Permanent Base. This is a logical location in that it is believed to have large quantities of glacial water just below the dirt while being as far possible towards the equator.

WHERE ON THE MOON?
It is pretty clear that the initial habitat, operations, and base will be at one of the lunar poles -- likely the southern lunar pole. The reasons for this are two-fold:
   1) There are peaks there with nearly continuous sunlight.
   2) There are permanently-shadowed craters with proven water ice and organics.

The lunar south pole has enough high-sunlight areas and permanently-shadowed craters to provide nearly a million residents. So there is a lot of room for the growth of a settlement up to country-level.

But the Moon's surface is as large as the continent of Africa. So there are plenty of other places on the Moon open for settlement. Simple dirt roads with self-driving cargo vehicles could deliver water and organics to settlements at more equatorial latitudes. But those settlements would probably need to have nuclear power in order to provide power throughout the two-week lunar night.

HOW ABOUT FREE SPACE?
Equatorial LEO (ELEO) has been identified as an important orbit with significantly lower radiation levels. It is conceivable that a path through tourism to settlement is possible. It could start with a space hotel in a highly-inclined orbit (covering most of the Earth). As the technology developed, the hotels could increase in size. Ultimately that technology could be applied to ELEO where a small but fully-fledged rotating space settlement could provide full artificial gravity for its residents of all ages.