A fresh photo above shows some construction activity at the Chekhov radar site near Moscow. The old Dunay-3U radar that was built there in the late 1970s as part of the missile defense system, but has been used mostly for space surveillance in recent years. Or, rather, half of the radar - it's eastward-looking part of the radar has been shut down.

Now there seems to be a fresh construction activity at the radar site - there is nothing there at the September 2015 Google Earth image:

There is also some fresh construction at the transmitter site (which Google doesn't show yet):

The purpose of this activity is not entirely clear. A rumor has it that it might be related to (among other things) to the Nudol ASAT program.