Over the past two days, defense contractor Raytheon (NYSE:RTN) has won a pair of Department of Defense contracts -- one of considerable size, and the other of considerable mystery.

The big contract Raytheon won this week was actually a firm-fixed-price contract "modification," exercising an option under a larger contract to supply the U.S. Missile Defense Agency with AN/TPY-2 advanced mobile radar systems.

A phased array, X-band radar, AN/TPY-2 forms an integral part of America's Ballistic Missile Defense System, where it is used for threat "surveillance, interceptor track, in-flight data uplink/downlink, target classification/ typing/ identification, and intercept assessment" functions. In the instant contract, Raytheon will receive $8.2 million to supply MDA with one AN/TPY-2 prime power unit. Added to the main contract award, this brings Raytheon's take on the work to a whopping $580.2 million.

Raytheon's more interesting contract win, however, came from the mysterious DARPA -- the Defense Advanced Research Projects Agency. On Thursday, DARPA awarded Raytheon $21.6 million under a cost-plus-fixed-fee contract to do ... something. As the Pentagon's contract announcement states: "The statement of work for this effort is classified."

Sure, they could tell you what the contract's for. But then they'd have to kill you -- probably with a drone strike.

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