Antares (rocket)

Antares

Launch of an Antares 230
Function	Medium expendable launch system
Manufacturer	Northrop Grumman (main) Pivdenmash (sub)[1] NPO Energomash (engines)
Country of origin	United States
Project cost	US$472 million until 2012[2]
Cost per launch	US$80−85 million[3]
Size
Height	110/120: 40.5 m (133 ft)[4][5] 130: 41.9 m (137 ft) 230/230+: 42.5 m (139 ft)[6]
Diameter	3.9 m (13 ft)[7][6]
Mass	110/120/130: 282,000–296,000 kg (622,000–653,000 lb)[5] 230/230+: 298,000 kg (657,000 lb)[6]
Stages	2 to 3[7]
Capacity
Payload to LEO
Mass	8,000 kg (18,000 lb)[8]
Associated rockets
Comparable	Delta II, Atlas III
Launch history
Status	110: retired 120: retired 130: retired 230: retired 230+: retired 300: planned
Launch sites	MARS, LP-0A
Total launches	18 (110: 2, 120: 2, 130: 1, 230: 5, 230+: 8)
Success(es)	17 (110: 2, 120: 2, 130: 0, 230: 5, 230+: 8)
Failure(s)	1 (130: 1)
First flight	110: April 21, 2013 120: January 9, 2014 130: October 28, 2014 230: October 17, 2016 230+: November 2, 2019 300: June 2025 (planned)
Last flight	110: September 18, 2013 120: July 13, 2014 130: October 28, 2014 230: April 17, 2019 230+: August 2, 2023
Type of passengers/cargo	Cygnus
First stage (Antares 100-series)
Empty mass	18,700 kg (41,200 lb)[5]
Gross mass	260,700 kg (574,700 lb)[5]
Powered by	2 × NK-33[9]
Maximum thrust	3,265 kN (734,000 lbf)[9]
Specific impulse	Sea level: 297 s (2.91 km/s) Vacuum: 331 s (3.25 km/s)[5]
Burn time	235 seconds[5]
Propellant	RP-1/LOX[9]
First stage (Antares 200-series)
Empty mass	20,600 kg (45,400 lb)[6]
Gross mass	262,600 kg (578,900 lb)[6]
Powered by	2 × RD-181[6]
Maximum thrust	3,844 kN (864,000 lbf)[6]
Specific impulse	Sea level: 311.9 s (3.059 km/s) Vacuum: 339.2 s (3.326 km/s)[6]
Burn time	215 seconds[6]
Propellant	RP-1/LOX
First stage (Antares 300-series)
Powered by	7 × Firefly Aerospace Miranda[10]
Propellant	RP-1/LOX
Second stage – Castor 30A/B/XL
Gross mass	30A: 14,035 kg (30,942 lb) 30B: 13,970 kg (30,800 lb) 30XL: 26,300 kg (58,000 lb)[5]
Propellant mass	30A: 12,815 kg (28,252 lb) 30B: 12,887 kg (28,411 lb)[5] 30XL: 24,200 kg (53,400 lb)[6]
Maximum thrust	30A: 259 kN (58,200 lbf) 30B: 293.4 kN (65,960 lbf)[9][5] 30XL: 474 kN (107,000 lbf)[11]
Burn time	30A: 136 seconds 30B: 127 seconds 30XL: 156 seconds[5][6]
Propellant	TP-H8299/aluminium[12]
[edit on Wikidata]

Antares (/ænˈtɑːriːz/), known during early development as Taurus II, is an expendable launch system developed by Orbital Sciences Corporation (later part of Northrop Grumman) and the Pivdenne Design Bureau to launch the Cygnus spacecraft to the International Space Station as part of NASA's COTS and CRS programs. Able to launch payloads heavier than 8,000 kg (18,000 lb) into low Earth orbit, Antares is the largest rocket operated by Northrop Grumman. Antares launches from the Mid-Atlantic Regional Spaceport and made its inaugural flight on April 21, 2013.^[13] Antares 100 was retired in 2014 and series 200 was retired in 2023 due to component unavailability. As of January 2024^[update] Antares 300 is under development.

NASA awarded Orbital a Commercial Orbital Transportation Services (COTS) Space Act Agreement (SAA) in 2008 to demonstrate delivery of cargo to the International Space Station. Orbital (and later Northrop Grumman) used Antares to launch its Cygnus spacecraft for these missions. As of August 2023^[update] it has only been used for Cygnus launches to the ISS, despite it being intended for commercial launches. Originally designated the Taurus II, Orbital Sciences renamed the vehicle Antares, after the star of the same name,^[14] on December 12, 2011.

Out of 18 total launches, Antares has suffered one failure. During the fifth launch on October 28, 2014, the rocket failed catastrophically, and the vehicle and payload were destroyed.^[15] The rocket's first-stage engines were identified as the cause for the failure. A different engine was chosen for subsequent launches, and the rocket had a successful return to flight on October 17, 2016.

The Antares has flown two major design iterations, the 100 series and 200 series. Both series have used a Castor 30XL as an upper stage but have differed on the first stage.^[16] The 100 series used two Kerolox powered AJ26 engines in the first stage and launched successfully four times. The 100 series was retired following a launch failure in 2014.^[17] The 200 series which first flew in 2016 also featured a Kerolox first stage but instead used two RD-181 engines along with other minor upgrades. The 200 series future became uncertain following the Russian invasion of Ukraine. Due to the first stage being produced in Ukraine and the engines in Russia, future production of the rocket was unable to be continued.^[16] As a result Northrop Grumman entered into an agreement with Firefly Aerospace to build the first stage of the Antares 300 series. Northrop also contracted with SpaceX for 3 Falcon 9 launches.^[18]