In article , Gene Cash wrote:
And a space station, in particular, *wants* to be as heavy as possible...
(The average annual reboost fuel consumption is, to a good first
approximation, unaffected. The reboosts take more fuel each, but
they're less frequent.)

Hm. I think I'd consider fuel budget more important than frequency of
reboosts.

Note what I said: the fuel budget is *unaffected*. Loosely speaking, the
requirement for reboost is that reboost thrust, averaged over the period
between reboosts, equal the air-drag force averaged over the same period.
Station frontal area affects fuel budget, but station mass does not.

The one place where mass makes a difference to reboosts is that it slows
down the effects of air drag. So if you reboost at the same frequency,
your altitude varies over a narrower range, while if you let the altitude
vary over the same range, reboosts are less frequent.

I didn't think a reboost was that inconvenient, if you have to
haul up the extra station mass *and* more fuel to keep it in orbit.

Please read what I wrote: you *don't* need more fuel. And the mass in
question is stuff that is already being hauled up there; the question is
whether to go to added inconvenience to get rid of it.

Reboosts actually are inconvenient, not least because they disrupt the
microgravity environment that is one major reason to have a station.
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