redesign of ONeill cylinder mirrors

--- In spacesettlers@yahoogroups.com, "millenial70" wrote:

> Actually this be might be chosen even in the inner solar system. It
> offers lots of advantages over an O'Neill design:
>
> It maximizes the amount of living area for any given cylinder
> dimensions; no area of the cylinder is needed to be used for
> transparent windows.
>
> It simplifies the problem of making the habitat radiation-shielded.
>
> It means less heat leakage into space, which in the asteroid belt
> could be a significant factor.
>
> It could make for a more sound structure as the cylinder would be
> composed of one strong material, and not half of it as glass (or
> is it quartz or something else?).
>
> The tube could be turned on and off, thus simulating a day/night
> cycle. This is a more elegant solution than having to move external
> mirrors around.

For the "light tube" where does the light come from?

TangoMan