what's this?

[totient]

what's this?

Hint: The reason this object is interesting is actually visible in the aerial photo, though it's hard to make out.

Answer in the comments.

Comments

[http://users.livejournal.com/cgull_/]

OK, this is a good puzzle.

They're...wind sensors, of a sort. 20 wind turbines, 15 on the long side of the building and 5 at the north end.

I can only find photos of the 5 at the end of the building, probably because that's all that was installed in the early stages of the project when the people involved made noise about it.

http://greensource.construction.com/news/080911Massport.asp

And now I don't have an excuse to ride out there. (Maybe I still do. Or maybe SCUL does.)

[palmwiz.livejournal.com]

Precisely! The current hit three (http://www.emagazine.com/view/?4324) on Google for "Logan Airport Office Building" has a picture of what I believe to be three of the 15 on the long side.