Bill Rutherford wrote:

> Is this because after a zillion years, every system WOULD be populated?

> Or do the various canon maps only show systems with populations, star
> ports, or other importance,and it's assumed there are other stars in
> the empty hexes that are essentially useless for travelling via jump?

> What about stars without planets?

My take, FWIW... (These ideas may not be well thought out, be warned...)

The maps show all stars. All stars have planets, or at least some sort of solar system.
Not all of these are easily habitable.

Planets tend to end up in some sort of ecological balance. On the one end, this
might be an industrial wasteland with zero or minimal native life, and with heavy
off-planet support (see below). On the other, it might be a garden world with way
fewer sophonts that current residents of this planet might imagine. EG I handwave
that Earth at near its current technology might be able to handle 1 billion residents,
with appropriate support, and with a "nice" ecosphere - wild animals still roaming
around on various continents, in the oceans, and so on. Wipe them out and Earth could
probably handle 50 billion, but of course everyone would be living in tower blocks.
One billion residents, with Imperial-level technology, could make Earth into a
garden world.

So what sort of support would be needed to support this sort of population? My answer
is orbital farms. The food has to come from somewhere, and I have a soft spot for the
"Silent Running" answer.

There are other options: people living off-planet, in orbital habitats, arcologies,
chandeliers, and so on. But still, the food has to come from somewhere...

(Forthcoming: a long post on food, but I digress.)

So, back to the idea of 'spare space': IMTU there is some. On occasion some movement
will spring up that wants to found its own society. Charismatic Leader Belle wants to
set up such a place, but his home planet a) has no spare space; and b) its rulers
don't want her New Ideal Society (tm) set up in their backyard. So they encourage
her to go a system or two off, and set up there. Naturally the target planet is not
exactly prime real estate (otherwise it *would* be populated), however, there are
some buildings and infrastructure there that can be re-used (courtesy of the late
Charismatic Leader Benne, whose colony died off a few centuries ago). (Cf Jonestown.)
If the colony succeeds, and especially if they can make it after the death of the
original leader, then congrats to them, otherwise...

Unsurprisingly, planets with 'spare space' tend to be hellworlds, or those with
tricky environments. A small colony could probably buy an asteroid and set up there,
but then they've got to terraform it. Or complete the terraforming that some previous
attempt didn't quite get around to finishing. And so on.

Anyway, some random thoughts on the topic. Hope these are helpful to someone.

Jonathan