Antares / Taurus II

Taurus II is a two-stage launch vehicle designed to provide responsive, low-cost, and reliable access to space for medium-class payloads weighing up to 5750 kg. Currently under development to demonstrate commercial re-supply of the International Space Station under a NASA Commercial Orbital Transportation Services (COTS) contract, the Taurus II launch system utilizes identical management approaches, engineering standards, production and test processes common to Orbital's family of highly successful small-class Pegasus®, Taurus®, and Minotaur launch vehicles. These proven launch technologies, along with hardware from one of the world's leading launch vehicle integrators, combine to provide cost-effective access to a variety of orbits for civil, commercial and military Delta II-class payloads.

The Taurus II launch vehicle will have a payload capacity of 4,750 to 6,250 Kg to low-Earth orbits (depending on altitude and inclination). The Cygnus spacecraft will be capable of delivering up to 2,300 Kg of pressurized or unpressurized cargo to the ISS, and will be capable of returning up to 1,200 Kg of cargo from ISS to Earth.

By serving as an anchor mission for Orbital's Taurus II rocket, the COTS project will not only benefit NASA's ISS operations with reliable commercial cargo service once the system is fully operational, but will also aid NASA's Earth and space science and planetary exploration programs with lower-cost launches of medium-class satellites," said Dr. Antonio L. Elias, Executive Vice President and General Manager of Orbital's Advanced Programs Group, which leads a company-wide team developing the Taurus II launch vehicle and the Cygnus spacecraft.

System Features Include:

• Large 3.9 meter fairing, capable of accommodating a variety of single and multiple payloads
• Substantial payload performance into a variety low inclination low-Earth orbits (LEO), sun-synchronous, geo-transfer or interplanetary orbits
• Streamlined vehicle/payload integration and testing via simplified avionics interfaces and offline payload encapsulation
• Designed for easy transportability and rapid set-up from a variety of launch sites
• Compatible with the Western Range at Vandenberg Air Force Base (VAFB), Eastern Range at Cape Canaveral Air Force Station and Wallops Flight Facility (WFF).)
• Initial launch capability for first mission in 2010
• Proven technology to meet mission requirements

Antares, the new name for the Taurus II, is a two-stage launch vehicle consisting of a liquid-fueled liquid Oxygen/refined kerosene first stage powered by two Aerojet Rocketdyne AJ26 engines. The second stage is an ATK CASTOR 30XL solid motor. Antares employs a 32.5 ft. (9.9 meter) fairing to protect Cygnus from atmospheric heating as it accelerates through Earth’s atmosphere.

From its launch site at Wallops Island, Virginia, Antares is capable of supporting midinclination and polar orbiting spacecraft weighing up to approximately 13,500 lb. (6123 kg) and 5,500 lb. (2495 kg), respectively.

A rocket and spacecraft developed by a private US company lifted off from a NASA launch pad 18 September 2013 [three years late] on a mission to deliver about 1,300 pounds (589 kilograms) of cargo to the International Space Station (ISS). The Antares rocket and Cygnus spacecraft, developed by Orbital Sciences, was launched at 10:58 a.m. (1458 GMT) from Virginia. The demonstration mission is the first operational flight in space for the Cygnus spacecraft. If the mission is successful, the company will begin regular resupply missions to the ISS.

Cygnus separated from the Antares rocket around 10 minutes after liftoff in what NASA called “a beautiful mission so far.” Once Cygnus goes into orbit, a pair of solar array wings will deploy from the base of the cylindrical spacecraft and will go through a series of checks and evaluations to make sure all systems are ready to approach the ISS. A rendezvous with the orbiting outpost is scheduled for Sunday. Astronauts aboard the ISS will use the station’s arm to capture Cygnus and then install it on the bottom side of the station’s Harmony module.

Orbital Sciences was selected in 2008 to work with NASA on the space agency’s Commercial Orbital Transportation Services (COTS) program, which helps US companies develop privately operated, cost-effective and safe space transportation systems. Another COTS partner company, Space Exploration Technologies (SpaceX), began working with NASA in 2006, and after a successful test flight in 2012, began flying regular cargo missions to the space station.

An Antares rocket carrying a Cygnus cargo spacecraft (both provided by Orbital Sciences) launched 13 July 2014 from NASA's Wallops Flight Facility, VA. Cygnus carried some 3,300 pounds of cargo to the station, including crew food and supplies, hardware, and scientific equipment and experiments.

On 28 October 2014, an Antares unmanned commercial rocket with supplies and equipment for the space station burst into fiery fragments just seconds after liftoff from Wallops Island, in the US state of Virginia off the Atlantic coast. Orbital Sciences Corporation, the company contracted by the US government to send supplies to the space station, said it will not launch another Antares rocket until the cause of Tuesday's explosion is determined.

"As far as next steps for the Antares, we will not fly until we understand the root cause and corrective action necessary to ensure it doesn't happen again," said Frank Culbertson, Executive Vice President and General Manager of Advanced Programs Group at Orbital Sciences Corporation. No one on the ground was hurt. The U.S. space agency, NASA, said the International Space Station crew "is in no danger of running out of food or other critical supplies."

Following an engine failure and subsequent explosion during the Antares launch in October 2014, the company halted all launches, struggling to find a replacement. The reliability of the RD-181 and similar engines made it the best choice. Russia’s design bureau NPO Energomash is to deliver 60 RD 181 engines for the Antares rocket first stage to American space technology manufacturer Orbital Sciences Corporation. The total cost of the deal is about $1 billion.

“We are committed to deliver 60 engines. Three options have been signed, each for 20 engines,” Vladimir Solntsev, executive director of Energomash, told the Izvestia newspaper 16 January 2015. “There is a firm contract for 20 engines, which we have started fulfilling, as we are due to supply the first two engines next June.”

NPO Energomash (RSC Energia is the managing organization of the enterprise) is planning to supply 60 new RD-181 rocket engines to the Orbital Sciences Corporation in the US. A firm contract for 20 engines was signed in January 2015. The 60 Russian engines will cost the customer about $1 billion, which includes a whole range of services – flight training, rocket engine installation and testing.

The first launch of the U.S.-made Antares rocket with Russian RD-181 engines was scheduled for March 1, 2016. Previously, these boosters were equipped with AJ-26 engines, based on the Soviet NK-33.

Russia supplied the first two RD-181 rocket engines for the Antares rocket to the US under the previously signed contract, the press center of the RSC Energia told the TASS news agency 04 August 2015. “On July 15, the first two RD-181 engines were shipped from Russia and delivered to the USA on 16 July,” the corporation said. Before shipment to the United States the engines underwent technological and hot fire tests. Originally, it was planned that the engines would be delivered to the customer in June. In 2015, Russia plans to supply a total of four RD-181 to the U.S., with four more to be shipped in 2016.

The agreement includes restrictions on the use of RD-181 units in military programs – rockets equipped with Russian engines should not be used for the launch of military spacecraft. The Delta IV launch vehicle has a domestically produced propulsion system that is capable of lifting all national security payloads.

On 31 May 2016 Orbital ATK conducted a full-power "hot fire" test of the upgraded first stage propulsion system of its Antares medium-class rocket using new RD-181 main engines. The 30-second test took place at 5:30 p.m. (EDT) on May 31, 2016 at Virginia Space’s Mid-Atlantic Regional Spaceport (MARS) Pad 0A. Initial indications are that the test was fully successful. Orbital ATK later purged and cleaned the engines of residual propellants and returned the first stage used in this test to the Horizontal Integration Facility for full reconditioning prior to its use on the OA-7 mission slated for later in 2016. The Orbital ATK team prepared the Antares rocket that will launch the OA-5 mission, which was in the final stages of integration, systems testing and check-out in preparation for launch in summer 2016.

The mission, known as OA-5, began on October 17, 2016 when Cygnus launched aboard an upgraded Antares rocket from NASA Wallops Flight Facility, marking Orbital ATK s return to flight operations in eastern Virginia. Upon arrival at the station, Cygnus delivered 5,300 pounds (2,400 kilograms) of cargo and science experiments to the astronauts. The Expedition 50 crew members loaded the cargo module with approximately 2,469 pounds (1,120 kilograms) of items for disposal prior to Cygnus departure. Orbiting on its own, free of the ISS, the S.S. Alan Poindexter Cygnus conducted two secondary mission objectives as part of its flight program: the Saffire-II payload experiment and the deployment of CubeSats to enhance weather forecasting capabilities. This is the second time Orbital ATK will use a Cygnus spacecraft as a platform for conducting science experiments in space.

On 11 November 2020 Northrop Grumman wad awarded two additional missions by NASA under the Commercial Resupply Services contract-2 (CRS-2) with launches occurring in 2023. Northrop Grumman will deliver a combined total of approximately 16,500 lbs. of cargo to the International Space Station during these missions. For the additional missions, Northrop Grumman’s Cygnus spacecraft will be carried into orbit by the company’s Antares launch vehicle from the Mid-Atlantic Regional Spaceport at NASA’s Wallops Flight Facility in eastern Virginia.

On Feb. 19, 2021 Northrop Grumman launched the company’s 15th resupply mission (NG-15) to the International Space Station under NASA’s Commercial Resupply Service-2 contract. The NG-15 mission’s Cygnus spacecraft launched aboard the company’s Antares rocket with nearly 8,000 pounds of scientific research, supplies and hardware for the crew aboard the station. Northrop Grumman names each Cygnus spacecraft in honor of individuals who have made substantial contributions to the United States’ commercial space program and human space flight. The NG-15 mission commemorates Katherine Johnson, a NASA mathematician and Black woman who not only broke through barriers of gender and race, but delivered calculations that were critical to the success of numerous human spaceflight missions. The “S.S. Katherine Johnson” will remain attached to the space station for approximately three months before departing with up to 8,200 pounds (approximately 3,720 kilograms) of disposal cargo.