You know you're addicted to Celestia when...

[selden]

you try to rotate a picture with the right mouse button

[BobHegwood]

Or, you press ENTER to see if a particular location is listed on a photograph of the Moon.

[Tech Sgt. Chen]

No matter how long you've been away, you always end up coming back for more.

[LordFerret]

...you find yourself standing outside at night looking up at the stars, feeling frustrated free-flight mode doesn't work here.

[John Van Vliet]

when you host your own Celestia web site
Internet Archive: Wayback Machine
http://web.archive.org/web/200602081559 ... no-ip.com/

[bdm]

... you freebase .CEL files.

[rthorvald]

... Your monitor has burn-ins of the virtual sun...

- rthorvald

[PlutonianEmpire]

... when you dedicate a forum to it.

Oh, wait.

[Chuft-Captain]

you try to rotate a picture with the right mouse button

I just tried to rotate this picture: http://saturn.jpl.nasa.gov/photos/image ... ageid=3277 with the right mouse button.
(This is not an un-common occurrence)

I think I'm addicted.

[julesstoop]

I often press 'enter' when I want to invoke a Google search, and I regularly mix up Celestia controls with Google Earth controls (pressing the wrong mouse butto to rotate a body's surface).

[Chuft-Captain]

... you don't need to heat the room in winter.

( the graphics card keeps the room at a pleasant 22degC )

[Enio]

When you try to create a very well made add-on, so well made that you never finish it... In my case I'm remaking the entire solar system.

[Reiko]

When you dream about it at night.

[asteroid]

You look up at the clock after playing with some tour and model plugins and find it's 3:38 a.m.

[LordFerret]

...when you post more than once in this thread.