 | |
| Module statistics | |
|---|---|
| COSPAR ID | 1998-067A |
| Part of | International Space Station |
| Launch date | 20 November 1998, 06:40 UTC |
| Launch vehicle | Proton-K |
| Mass | 19,323 kg (42,600 lb)[a] |
| Length | 12.56 m (41.2 ft) |
| Diameter | 4.11 m (13.5 ft) |
| Pressurisedvolume | 71.5 m3 (2,520 cu ft)[2] |
| Configuration | |
_module.svg) Parts ofZarya, click for a closer look with captions | |
Zarya (Russian:Заря,lit. 'Sunrise'),[b] also known as theFunctional Cargo Block (Russian:Функционально-грузовой блок), is the first module of theInternational Space Station (ISS). Launched on 20 November 1998 atop aProton-K rocket, the module would serve as the ISS's primary source of power, propulsion, and guidance during its early years. As the ISS expanded, Zarya's role shifted primarily to storage, both internally and in its external fuel tanks.[4] A descendant of theTKS spacecraft used in theSalyut programme,Zarya was built in Russia but financed by the United States. Its name, meaning "sunrise," symbolizes the beginning of a new era of international space cooperation.[5]
The design ofZarya traces its heritage to theTKS spacecraft developed for theSalyut programme. The TKS consisted of two parts: theVA spacecraft, acapsule that housed cosmonauts during launch and re-entry, and theFunctional Cargo Block (FGB), which contained a large pressurized cargo compartment. This arrangement allowed the VA capsule to return to Earth while leaving the FGB attached as a station module.[6] FGB modules were added toSalyut 6 andSalyut 7, and five ofMir's modules were also based on the FGB design. An FGB also served as the upper stage of thePolyus spacecraft, that failed to reach orbit on the firstEnergia launch in 1987.[7]
Zarya itself was built between December 1994 and January 1998 at theKhrunichev State Research and Production Space Center in Moscow, funded by aUS$220 million (equivalent to US$470 million in 2024) NASA contract,[8] significantly less than the alternative "Bus-1" design proposed byLockheed Martin (US$450 million in 1994, equivalent to US$950 million in 2024).
Commentators in the West noted that Zarya was completed and launched more quickly and cheaply than expected in the post-Soviet era. Some suggested that its FGB structure, like that of most Mir modules, was largely assembled frommothballed hardware originally built for the Soviet-eraSkif laser weapon program, which was canceled after the loss of the first Polyus spacecraft. Under this interpretation, NASA's funding ofZarya effectively underwrote the cost of theZvezda service module, Russia's primary early contribution to the ISS.
As part of the NASA contract, Khrunichev also assembled much of a contingency flight spare, FGB-2, which was likewise believed to incorporate unused hardware. Roscosmos later funded its completion asNauka, which launched to the ISS in 2021.[9]
Zarya has a mass of 19,323 kilograms (42,600 lb), is 12.56 meters (41.2 ft) long, and 4.11 meters (13.5 ft) wide at its widest point.
The module has threedocking ports: one at the aft end (the rear of the station in its usual orientation and direction of travel) and two on a "docking sphere" at the opposite forward end, one facing forward and the othernadir (Earth-facing). A planned zenith (space-facing) port in the docking sphere was sealed with a spherical cover after a design change.[10] The forward port is attached toPressurized Mating Adapter-1 (PMA-1), which connects to theUnity module, with PMA-1 serving as the link between theRussian Orbital Segment (ROS) and theUS Orbital Segment (USOS). The aft port is connected to theZvezda service module. The nadir port was used by a couple of visitingProgress cargo spacecraft until 2010, when theRassvet module was docked; since then, visiting spacecraft have used Rassvet's nadir port instead.[11]
For power,Zarya is equipped with twosolar arrays measuring 10.67 by 3.35 meters (35 by 11 ft) and sixnickel-cadmium batteries, providing an average of 3 kilowatts of power. The solar arrays have been partially retracted[12] to allow deployment of the P1/S1 radiators on theIntegrated Truss Structure. While they still generate power, they no longer produce the full 3 kilowatts (4.0 hp) that was available when fully unfurled.[13]
For propulsion,Zarya has 16 external fuel tanks capable of storing up to 6.1 tonnes (13,000 lb) of propellant. This capability was mandated by NASA in 1997 to ensure that the FGB could independently store and transfer propellant, even if theZvezda Service Module was delayed.[14]Zarya is equipped with 24 large steering jets, 12 small steering jets, and two large engines previously used for reboost and major orbital maneuvers. With the docking ofZvezda, these engines were permanently disabled. The propellant tanks that once fueled Zarya’s engines are now used to store additional fuel forZvezda.
Zarya was launched on 20 November 1998 atop a RussianProton-K rocket fromBaikonur Cosmodrome Site 81 in Kazakhstan, into a 400-kilometer (250 mi) orbit, with a planned operational lifetime of at least 15 years.
The first U.S. contribution to the ISS, theUnity module, followed on 4 December 1998 aboardSTS-88. During the mission, CommanderRobert Cabana maneuvered theSpace Shuttle Endeavour to within 10 meters (33 ft) ofZarya, enabling Mission SpecialistNancy Currie to capture the module with theShuttle's robotic arm and attach its forward port toPressurized Mating Adapter-1, which was already mounted on the aft end ofUnity. AstronautsJerry Ross andJames Newman then conducted two spacewalks to connect electrical and data cables between the two modules. On 10 December 1998, Cabana and Russian cosmonautSergei Krikalev ceremonially entered the new orbital outpost for the first time.
The crew of STS-88 departed on 13 December 1998, leavingZarya to autonomously manage the station’s power, propulsion, and guidance, a role it was originally intended to perform for only six to eight months. However, the station would remain unoccupied for nearly two years due to delays with the Russian service module,Zvezda. Before the arrival ofZvezda, the station was visited twice by theSpace Shuttle for short-duration outfitting andreboost missions:STS-96 in May 1999 andSTS-101 in May 2000.Zvezda was launched on 12 July 2000 and, on 26 July, automatically docked its forward port to the aft port ofZarya.
| Spacecraft | Launch (UTC) | Carrier rocket | Launch pad | Docking | Undocking | Deorbit | Remarks |
|---|---|---|---|---|---|---|---|
| Progress M1-4 | 16 November 2000 01:32:36 | Soyuz‑U | Site 1/5 | 18 November 2000 03:48 | 1 December 2000 16:23 | 8 February 13:50 | ISS-2P.[15] The automaticKurs docking system failed, and the manual backup,TORU, was used for the docking. Following undocking, Progress M1-4 spent 25 days in free flight, prior to redocking with the same port.[16] |
| 26 December 2000 10:54 | 8 February 2001 11:26 | ||||||
| Progress M-64 | 14 May 2008 20:22:56 | Soyuz‑U | Site 1/5 | 16 May 2008 21:39 | 1 September 2008 19:46 | 8 September 2008 21:33 | ISS-29P |
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.svg) | TKS spacecraft test missions |
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| VA spacecraft test flights | |||
| Functional Cargo Block (FGB) derived hardware | |||
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