It's a surveying symbol. It is called a "reticle"...

Liberal Ignorance alert! - Sense, Nonsense, and Symbols

from thesteadydrip.com 

Here is the background story.


Sarah Palin used the symbol on a map illustrating the focus of her campaign work. After the Arizona shooting leftists said she was encouraging nutjobs to assassinate candidates.  Why leftists would think that a potsmoking, acid rock fan, who burns USA flags and likes the "Communist Manifesto" would be inspired by Sarah Palin is beyond my ability to explain.

I have received emails that insist that this is a gun sight.  Evidently they have not done any research.  So I guess I will need to do it for them.

http://egsc.usgs.gov/isb/pubs/booklets/symbols/topomapsymbols.pdf

It is a surveying symbol.  It is called a "reticle".  It could mean a couple things. For one, it's what you see through a transit when sighting a target. The graduated lines on the vertical cross hair are known as stadia, and are used to calculate distance. It could also be a target used for rectification of aerial photography by a known coordinate at the intersection of the cross hairs. But overall, it means that the intersection is of a known coordinate, or one you wish to obtain. The symbol is also common in optical instruments used for astronomy, and are popular in graphical user interfaces as a precision pointer. The reticle was invented by Robert Hooke, and dates to the 17th century.
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Stadia marks, also called stadia lines or stadia hairs, are crosshairs on the reticle of a theodolite or other surveying instrument that allow stadiametric rangefinding.