This was probably already posted but I couldn't find it in the forums. Anyone know what it is? Who made it and when?
37 37'38.69"N 116 50'48.38"W
Try turning on the Google Earth Community Layer, under Gallery. Some kind of bombing range. I'm going to guess long range missiles since that's the only think I can think of that would need a target almost 1 mile across. Look closely at ground and you will see lots of bomb craters.
Aircraft Bombing Range
I believe that it is just a simple bombing range.
If you go to elevation: 3659 (or thereabouts) at to coordinates: 42░42'48"N 115░33'53.72" W, you will see another example of a similar range (even of larger size : some 3,900ft. in diameter). This is part of the practice range at Mountain Home Air Force Base, Idaho. The one that you were looking at was part of the joint, Nellis Air Force Base, Nevada/China Lake proving grounds (amongst others).
Hope this helps.