US Spy Satellite Is the Largest Satellite In the WorldLast Sunday, at 5:58pm, the USAF launched NRO LR-32, a secret US military spy satellite so massive that it required this Delta IV Heavy rocket to reach orbit. In fact, the mysterious spacecraft is the largest satellite in the world.

US Spy Satellite Is the Largest Satellite In the WorldAccording to the National Reconnaissance Office's Director Bruce Carlson, NRO LR-32 is indeed "the largest satellite in the world." The NRO is dedicated to the design, manufacturing, and operation of all the United States reconnaissance satellites. No official information has been published, but it "is believed to be an eavesdropping satellite positioned high above the equator in geosynchronous orbit" with a antenna the size of a football field once it's extended in orbit.

The Delta IV Heavy is the largest rocket in the world in size, capable of producing 1.9 million pounds of thrust using its three engines. [ULA and Launch Photography]

Images by Ben Cooper, from Launch Photography