Aug 042012
From HERE a photo of USS Dewey, DDG-105, an Arleigh Burke class destroyer with a great big interesting thing mounted to it. Also appears to have some substantial generators. Go to the link for higher-rez images.
So what do we have here? Inside the dome there appears to be a sizable telescope. But a telescope itself would not seem to need the sort of electrical power that the Caterpillar generators would provide. There is also what appears to be a sensor system mounted further aft.