radioactive weapons. critical capabilities when it comes to monitoring global hot spots, such as syria and iran. >> whether it's fallen signals or tracing weapons, whether we're making sure that the treaties that the u.s. has signed are actually being enforced, we contribute to all of those missions. >> i imagine the iranian nuclear agreement falls into that category. >> we contribute to that missionary. >> to see where the data from the agency is collected, we came here. a place you've probably never heard of. a place you've certainly never seen. until now. >> we're approaching the mission ground station at white sands, new mexico. the very existence of this ground station and others in the u.s. was classified until 2008 and we're the first reporters allowed inside.