About 3 miles from my house is a massive industrial building that is being demolished. Within the property is this, what looks to be an observatory. The concrete walls appear to be about 30' X 30'. I know someday I'll be sick when I see it get the wrecking ball. Even if I had the means, I doubt my wife would approve of a massive dome in our back yard.

Looks like about a 15 foot dome. Would make a nice small planetarium with a bit of work. Sad.

Ron, looks to me like 15 is very conservative.....I'd guesstimate closer to 24.

How bout it Craig? How big is it?

Tough call. This picture was taken with the camera at arm's length over a chain link fence. The vertical concrete wall sections looked too big to be 4' and to small to be 8' so I guessed they are 6'. I just might have to do some covert nighttime reconnicense op to check it out. No security or motion sensors. Cue the 'mission impossible' theme.

Here's a google earth image of it. I was on the northeast corner of it to the upper right when I took the picture.

The average car length is about 16 to 18 feet so I make it to be around 20 in diameter. Anybody care to concur?

I'll agree with that. Makes it an even better candidate for planetarium use, that is unless someone has an extremely large telescope.

With a dome that big for observatory use, a 7'-8' base wall for a standard entry door would make it rediculously big. I'd pour a round slab in a round foundation base. The dome & rollers a foot off the ground. And then hasp/padlock the shutter on the outside as the door to get in. Step over the 12" base track wall to walk in.

AUGH! It's gone! I drove by and the concrete walls are there but the dome is gone. I don't know if it was carefully taken off for re-use, or ripped off for scrap metal. D'oh!