Ergo dixit:
The NRO satellites are operated by the United States National Reconnaissance Office. The NRO missions are generally classified, so their exact purposes and orbital elements are not available to the public.
Wikipedia dixit:
“The Atlas V was developed by Lockheed Martin Commercial Launch Services as part of the US Air Force Evolved Expendable Launch Vehicle (EELV) program and made its inaugural flight on August 21, 2002. The vehicle operates out of Space Launch Complex 41 at Cape Canaveral Air Force Station and Space Launch Complex 3-E at Vandenberg Air Force Base. Lockheed Martin Commercial Launch Services continues to market the Atlas V to commercial customers worldwide.
The Atlas V first stage, the Common Core Booster (CCB), is 12.5 ft (3.8 m) in diameter and 106.6 ft (32.5 m) in length. It is powered by a single Russian RD-180 main engine burning 627,105 lb (284,450 kg) of liquid oxygen and RP-1. The booster operates for about four minutes, providing about 4 meganewtons (860,000 lbf) of thrust. Thrust can be augmented with up to five Aerojet strap-on solid rocket boosters, each providing an additional 1.27 meganewtons (285,500 lbf) of thrust for 94 seconds. The Atlas V is the newest member of the Atlas family. Compared to the Atlas III vehicle, there are numerous changes. Compared to the Atlas II, the first stage is a near-redesign. There was no Atlas IV. The “1.5 staging” technique was dropped on the Atlas III, although the same RD-180 engine is used. The RD-180 features a dual-combustion chamber, dual-nozzle design and is fueled by a kerosene/liquid oxygen mixture. The main-stage diameter increased from 10 feet to 12.5 feet. As with the Atlas III, the different mixture ratio of the engine called for a larger oxygen tank (relative to the fuel tank) compared to Western engines and stages. The first stage tanks no longer use stainless steel monocoque “balloon” construction. The tanks are isogrid aluminum and are structurally stable when unpressurized. Use of aluminum, with a higher thermal conductivity than stainless steel, requires insulation for the liquid oxygen. The tanks are covered in a polyurethane-based layer. Accommodation points for parallel stages, both smaller solids and identical liquids, are built into first stage structures.
The Centaur upper stage uses a pressure stabilized propellant tank design and cryogenic propellants. The Centaur stage for Atlas V is stretched 5.5 ft (1.68 m) relative to the Atlas IIAS Centaur and is powered by either one or two Aerojet Rocketdyne RL10A-4-2 engines, each engine developing a thrust of 99.2 kN (22,300 lbf). The inertial navigation unit (INU) located on the Centaur provides guidance and navigation for both the Atlas and Centaur, and controls both Atlas and Centaur tank pressures and propellant use. The Centaur engines are capable of multiple in-space starts, making possible insertion into low Earth parking orbit, followed by a coast period and then insertion into GTO. A subsequent third burn following a multi-hour coast can permit direct injection of payloads into geostationary orbit. As of 2006, the Centaur vehicle had the highest proportion of burnable propellant relative to total mass of any modern hydrogen upper stage and hence can deliver substantial payloads to a high energy state.
The standard payload fairing sizes are 4 or 5 meters in diameter. The 4.2-meter fairing, originally designed for the Atlas II booster, comes in three different lengths, the original 9-meter high version, as well as fairings 10 meters (first flown on the AV-008/Astra 1KR launch) and 11 meters (seen on the AV-004/Inmarsat-4 F1 launch) high. Lockheed Martin had the 5.4-meter (4.57 meters usable) payload fairing for the Atlas V developed and built by RUAG Space (former Oerlikon Space) in Switzerland. The RUAG fairing uses carbon fiber composite construction, based on flight-proven hardware from the Ariane 5. Three configurations will be manufactured to support the Atlas V. The short (10-meter long) and medium (13-meter long) configurations will be used on the Atlas V 500 series. The 16-meter long configuration would be used on the Atlas V Heavy. The classic fairing covers only the payload, leaving the Centaur stage exposed to open air. The RUAG fairing encloses the Centaur stage as well as the payload.”
Video credit: United Launch Alliance