OrbitalHub

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

Orbital Sciences Corporation has announced that Atlas V will be the launch vehicle that will help the company fulfill its Commercial Resupply Services (CRS) commitment to NASA. Orbital’s Antares will undergo an upgrade of the main propulsion system.

From the December 9, 2014 press release:

“Orbital Sciences Corporation […] today announced new details in its plans to resume cargo flights to the International Space Station (ISS) and to accelerate the introduction of an upgraded Antares launch vehicle. In formulating its go-forward plans, the company’s primary objective is to fulfill its commitment to NASA for ISS cargo deliveries with high levels of safety and reliability and minimum disruption to schedules. As previously announced, these plans are expected to allow Orbital to accomplish all remaining cargo deliveries under its current Commercial Resupply Services (CRS) contract with NASA by the end of 2016 and with no cost increase to the space agency.

The company’s go-forward plans for the CRS program and Antares launch vehicle include these major elements:

Atlas V Launch: Orbital has contracted with United Launch Alliance for an Atlas V launch of a Cygnus cargo spacecraft from Cape Canaveral, Florida, in the fourth quarter of 2015, with an option for a second Atlas V launch in 2016 if needed. The Atlas rocket’s greater lift capacity will allow Cygnus to carry nearly 35% more cargo to the ISS than previously planned for CRS missions in 2015.

Antares Propulsion Upgrade: The company has confirmed its ability to accelerate the introduction of a new main propulsion system for the Antares rocket and has scheduled three additional CRS launches in the first, second and fourth quarters of 2016 using the upgraded vehicle. The greater payload performance of the upgraded Antares will permit Cygnus spacecraft on each of these missions to deliver over 20% more cargo than in prior plans. With necessary supplier contracts now in place, the first new propulsion systems are expected to arrive at the Antares final assembly facility at Wallops Island, Virginia in mid-2015 to begin vehicle integration and testing.

Wallops Launch Site Repairs: The Mid-Atlantic Regional Spaceport (MARS) has assessed the clean-up, repair and reconstruction work necessary to return the Wallops launch complex to operational status. Current plans call for repairs to be substantially completed by the fall of 2015, with recertification taking place before year end.

The flexibility of Orbital’s Cygnus cargo spacecraft to accommodate heavier cargo loads, together with the greater lift capacity of the Atlas V and upgraded Antares vehicles, will allow the company to complete all currently contracted ISS deliveries in four missions instead of the five previously planned flights over the next two years. In addition, the company’s revised approach is not expected to create any material adverse financial impacts in 2015 or future years as Orbital carries out the CRS cargo delivery and Antares propulsion upgrade programs.”