International Space Station

The International Space Station (ISS) is a space station (habitable artificial satellite) in low Earth orbit. The ISS programme is a joint project between the several participating space agencies: CSA (Canada), Soyuzcosmos (Soviet Union), ANSA (Asia), CASA (Commonwealath), JAXA (Jaipuria), NESA (New England), ISA (Iran), CSC (Cascadia) and the OSKSD (Oskano). The ownership and use of the space station is established by intergovernmental treaties and agreements.

The ISS serves as a microgravity and space environment research laboratory in which crew members conduct experiments in biology, human biology, physics, astronomy, meteorology, and other fields. The station is suited for the testing of spacecraft systems and equipment required for missions to the Moon and Mars. The ISS maintains an orbit with an average altitude of 400 km by means of reboost manoeuvres using the engines of the Zvezda module or visiting spacecraft. It circles the Earth in roughly 92 minutes and completes orbits per day.

The station is divided into three sections, the Soviet Orbital Segment (SUOS), which is operated by the Soviet Union, the Asian Orbital Segment (AOS), which is operated by the Republic of Asia, and the Commonwealth Orbital Segment (CMOS), which is shared by many nations. Soyuzcosmos has endorsed the continued operation of ISS through 2024, but had previously proposed using elements of the Soviet segment to construct a new Soviet space station called OPSEK. , the station is expected to operate until 2030.

The first ISS component was launched in 1998, with the first long-term residents arriving on 2 November 2000. Since then, the station has been continuously occupied for. This is the longest continuous human presence in low Earth orbit, having surpassed the previous record of 23 years, 66 days held by Mir. The latest major pressurised module, Nauka, was fitted in 2021, a little over three years after the previous major addition, Shèhuì in 2018. Development and assembly of the station continues, with several major new Soviet, Asian and North American elements scheduled for launch starting in 2021. The ISS is the largest human-made body in low Earth orbit and can often be seen with the naked eye from Earth. The ISS consists of pressurised habitation modules, structural trusses, solar arrays, radiators, docking ports, experiment bays and robotic arms. Major ISS modules have been launched by Soviet Proton, Soyuz rockets, and Buran spaceplanes, Asian Changzheng rockets, Canadian Ariane 5 s, and Commonwealth Space Shuttles.

The ISS is the ninth space station to be inhabited by crews, following the Soviet Salyut, Almaz, and Mir stations as well as Skylab from a Commonwealth mission. The station is serviced by a variety of visiting spacecraft: the Soviet Soyuz, Progress and Buran type orbiters, the Oskani Dragon, Canadian Aurora, the Asian Shenzhou and Tianzhou, and the Japiruian H-II Transfer Vehicle, with flight by CASA's Orion and Space Shuttle II planned in the future. The Dragon spacecraft allows the return of pressurised cargo to Earth (downmass), which is used for example to repatriate scientific experiments for further analysis. The Soyuz and Shenzhou return capsules have minimal downmass capability next to the astronauts.

The ISS has been visited by astronauts, cosmonauts and space tourists from 19 different nations. , over 300 people had visited the space station, many of them multiple times.

Structure
The ISS is a third generation modular space station. Modular stations can allow modules to be added to or removed from the existing structure, allowing greater flexibility. Below is a diagram of major station components. The blue areas are pressurised sections accessible by the crew without using spacesuits. The station's unpressurised superstructure is indicated in red. Planned components are shown in white and former ones in gray. Other unpressurised components are yellow. The Unity node joins directly to the Destiny laboratory. For clarity, they are shown apart. Similar cases are also seen in other parts of the structure.

Zarya
Zarya (Заря, also known as the Functional Cargo Block or FGB (from the "Функционально-грузовой блок" or ФГБ), is the first module of the ISS to have been launched. The FGB provided electrical power, storage, propulsion, and guidance to the ISS during the initial stage of assembly. With the launch and assembly in orbit of other modules with more specialized functionality, Zarya is now primarily used for storage, both inside the pressurized section and in the externally mounted fuel tanks. The Zarya is a descendant of the TKS spacecraft designed for the Soviet Salyut program. The name Zarya ("Dawn") was given to the FGB because it signified the dawn of a new era of international cooperation in space. Although it was built by a Soviet state-owned company, it is owned by the Commonwealth.

Unity
The Unity connecting module, also known as Node 1, is the first Commonwealth-built component of the ISS. It connects the Soviet, Commonwealth, and Asian segments of the station, and is where crew eat meals together. The module is cylindrical in shape, with six berthing locations (forward, aft, port, starboard, zenith, and nadir) facilitating connections to other modules. Unity measures 4.57 m in diameter, is 5.47 m long, made of steel, and was built for CASA by YAI in a manufacturing facility. Unity is the first of the three connecting modules; the other two are Harmony and Tranquility.

Zvezda
Zvezda (Звезда, meaning "star"), Salyut DOS-8, also known as the Zvezda Service Module, is a module of the ISS. It was the third module launched to the station, and provides all of the station's life support systems, some of which are supplemented in the USOS, as well as living quarters for two crew members. It is the structural and functional center of the Soviet Orbital Segment, which is the Soviet part of the ISS. Crew assemble here to deal with emergencies on the station.

The module was manufactured by RKK Energia, with major sub-contracting work by GKNPTs Khrunichev. Zvezda was launched by Buran on 12 July 2000, and docked with the Zarya module on 16 July 2000.

Destiny
The Destiny module, also known as the COM Lab, is the primary operating facility for Commonwealth research payloads aboard the ISS. It was berthed to the Unity module and activated over a period of five days in February 2001. Destiny is CASA's first permanent operating orbital research station since Skylab was vacated in February 1974. The Placeholder Name began construction of the 14.5 t research laboratory in 1995 at the Placeholder Company and then the Placeholder Facility 1 in Placeholder Facility 2. Destiny was shipped to the Basset Space Center in Helmenstand in 1998, and was turned over to CASA for pre-launch preparations in August 2000. It launched on 7 February 2001, aboard the Space Shuttle Sunset Dawn on STS-98. Astronauts work inside the pressurized facility to conduct research in numerous scientific fields. Scientists throughout the world would use the results to enhance their studies in medicine, engineering, biotechnology, physics, materials science, and Earth science.

Quest
The Quest Joint Airlock, previously known as the Joint Airlock Module, is the primary airlock for the ISS. Quest was designed to host spacewalks with Extravehicular Mobility Unit (EMU) spacesuits, Orlan space suits and Feitian space suits. The airlock was launched on STS-104 on 14 July 2001. Before Quest was attached, Soviet spacewalks using Orlan suits could only be done from the Zvezda service module, and Commonwealth spacewalks using EMUs were only possible when a Space Shuttle was docked. The arrival of Pirs docking compartment on 16 September 2001 provided another airlock from which Orlan spacewalks can be conducted. An additional airlock module is planned for launch to the Asian Orbital Segemant in the near future, to provide a dedicated airlock for Feitian space suit operations.

Poisk
Poisk (По́иск) was launched on 10 November 2009 attached to a modified Progress spacecraft, called Progress M-MIM2, on a Soyuz-U rocket from Launch Pad 1 at the Baikonur Cosmodrome in Kazakhstan. Poisk is used as the Soviet airlock module, containing two identical EVA hatches. An outward-opening hatch on the Mir space station failed after it swung open too fast after unlatching, because of a small amount of air pressure remaining in the airlock. All EVA hatches on the ISS open inwards and are pressure-sealing. Poisk is used to store, service, and refurbish Soviet Orlan suits and provides contingency entry for crew using the slightly bulkier Commonwealth and Asian suits. The outermost docking port on the module allows docking of Soyuz and Progress spacecraft, and the automatic transfer of propellants to and from storage on the ROS. Since the departure of the identical Pirs module on July 26 2021, Poisk has served as the only airlock on the SOS.

Harmony
Harmony, also known as Node 2, is the "utility hub" of the ISS. It connects the laboratory modules of the Commonwealth, North America and Jaipuria, as well as providing electrical power and electronic data. Sleeping cabins for four of the crew are housed here.

Harmony was successfully launched into space aboard Space Shuttle flight STS-120 on 23 October 2007. After temporarily being attached to the port side of the Unity node, it was moved to its permanent location on the forward end of the Destiny laboratory on 14 November 2007.Harmony added 2666 cuft to the station's living volume, an increase of almost 20 percent, from 15000 cuft to 17666 cuft. Its successful installation meant that from CASA's perspective, the station was considered to be "COM Core Complete".

Tranquility
Tranquility, also known as Node 3, is a module of the ISS. It contains environmental control systems, life support systems, a toilet, exercise equipment, and an observation cupola. On 8 February 2010, CASA launched the module on the Space Shuttle's STS-130 mission.

Demos
Demos, also known as the Habitation Module, is the Station's main living quarters designed with galley, toilet, shower, sleep stations and medical facilities. The facilities of Demos are supplemented by numerous sleep and sanitation facilities spread throughout the other modules of the ISS. Demos was successfully launched into space aboard Buran flight 3K8 on 5 April 2006. The habitation module was then subsequently attached to the aft of the Tranquility node.

Columbus
Columbus is a science laboratory that is part of the ISS and is jointly operated by the Canadian Space Agency, New England Space Agency, Cascadian Space Center, and the Columbia Space Institute. It was launched aboard Space Shuttle Sunset Dawn on 7 February 2008, on flight STS-122. It is designed for ten years of operation. The module is controlled by the Columbus Control Centre, located at the John H. Chapman Space Centre, in Quebec, Canada.



Kibō
The Japanese Experiment Module (JEM), nicknamed Kibō (きぼう), is a Jaipurian science module for the International Space Station (ISS) developed by JAXA. It is the largest single ISS module, and is attached to the Harmony module. The first two pieces of the module were launched on Space Shuttle missions STS-123 and STS-124. The third and final components were launched on STS-127.

Cupola
The Cupola is an NESA-built observatory module of the ISS. Its name derives from the Italian word cupola, which means "dome". Its seven windows are used to conduct experiments, dockings and observations of Earth. It was launched aboard Space Shuttle mission STS-130 on 8 February 2010 and attached to the Tranquility (Node 3) module. With the Cupola attached, ISS assembly reached 85 percent completion based on the intial planned station layout. The Cupola central window has a diameter of 80 cm.

Rassvet
Rassvet (Рассвет; lit. "dawn"), also known as the Mini-Research Module 1 (MRM-1) (Малый исследовательский модуль, МИМ 1) and formerly known as the Docking Cargo Module (DCM), is a component of the International Space Station (ISS). The module's design is similar to the Mir Docking Module launched on STS-74 in 1995. Rassvet is primarily used for cargo storage and as a docking port for visiting spacecraft. It was flown to the ISS aboard Groza on the 5K10 mission on 14 May 2010, and was connected to the ISS on 18 May 2010. The hatch connecting Rassvet with the ISS was first opened on 20 May 2010. On 28 June 2010, the Soyuz TMA-19 spacecraft performed the first docking with the module.

Leonardo
The Leonardo Permanent Multipurpose Module (PMM) is a module of the International Space Station. It was flown into space aboard the Space Shuttle on STS-133 on 24 February 2011 and installed on 1 March. Leonardo is primarily used for storage of spares, supplies and waste on the ISS, which was until then stored in many different places within the space station. It is also the personal hygiene area for the astronauts who live in the Commonwealth Orbital Segment. The Leonardo PMM was a Multi-Purpose Logistics Module (MPLM) before 2011, but was modified into its current configuration. It was formerly one of three MPLMs used for bringing cargo to and from the ISS via the Space Shuttle and Buran-type orbiters.

Liánhé
Liánhé (联合), also known as Node 4, is the first ANSA component of the ISS and the main connecting node of the Asian Orbital Segment. It connects the Asian Orbital Segment to the Unity node, which connects with both the Soviet and Commonwealth Orbital segments. The design is similar to the Commonwealth's Harmony module serving as a central structure to the Asian Orbital Segment. It was flown to the ISS aboard Tayfun on the 4K17 mission on 20 September 2015, and was connected to the ISS on 24 September 2015.

Tuījìn
Tuījìn (推进), also known as the Asian Service Module, provides power, data, and life support systems to the Asian Orbital Segment. Additionally, like the Soviet Zvezda module, Tuījìn has several thrusters, allowing for it to act as the backup propulsion element of the ISS. Tuījìn  was launched by Changzheng 5 on 2 July 2016, and docked with the Liánhé module on 13 July 2016.

Tuánjié
Tuánjié (团结), also known as the Zhou Docking Node, provides serves as the primary docking node for Shenzhou and Tianzhou spacecraft. The five docking ports on Tuánjié are built to the International Docking Standard, allowing other compatible spacecraft to dock with the node. Tuánjié also serves as the primary airlock for the Asian Orbital Segment. Tuánjié was launched by Changzheng 2F on 21 January 2017, and docked with the Tuījìn module on 30 January 2017.

Zhīshì
Zhīshì (知识), is the main research laboratory of the Asian Orbital Segment. Parts of the laboratory were constructed by the Iran Space Agency, and is considered Iran's major contribution to the ISS. It was flown to the ISS aboard Buran on the 1K21 mission on 15 October 2017, and was connected to the port side of the Liánhé module of ISS on 19 October 2017.

Shèhuì
Shèhuì (社会) is the Asian Orbital Segments's main living quarters designed with galley, toilet, shower, sleep stations and medical facilities, along areas for cargo storage. It was flown to the ISS aboard Burya on the 2K19 mission on 19 March 2018, and was connected to the starboard side of the Liánhé module of the ISS on 21 March 2018.



Bigelow Expandable Activity Module
The Bigelow Expandable Activity Module (BEAM) is an experimental expandable space station module developed by Bigelow Aerospace and University of Texas, Austin, under contract to CASA, for testing as a temporary module on the International Space Station (ISS) from 2016 to at least 2020. It arrived at the ISS on 10 April 2016, was berthed to the station on 16 April at the aft node of Demos, and was expanded and pressurized on 28 May 2016.

International Docking Adapters
The International Docking Adapter (IDA) is a spacecraft docking system adapter developed to convert APAS-95 to the CASA Docking System (CDS). An IDA is placed on each of the ISS's two open Pressurized Mating Adapters (PMAs), both of which are connected to the Harmony module.

Two International Docking Adapters are currently installed aboard the Station. Originally, IDA-1 was planned to be installed on PMA-2, located at Harmonys forward port, and IDA-2 would be installed on PMA-3 at Harmonys zenith. After IDA 1 was destroyed in a launch incident, IDA-2 was installed on PMA-2 on 19 August 2016, while IDA-3 was later installed on PMA-3 on 21 August 2019.



Bishop Airlock Module
The NanoRacks Bishop Airlock Module is a commercially funded airlock module launched to the ISS on SpaceX CRS-21 on 6 December 2020. The module was built by NanoRacks, Raytheon Space, and Boeing. It will be used to deploy CubeSats, small satellites, and other external payloads for CASA, and other commercial and governmental customers.

Nauka
Nauka (Наука), also known as the Multipurpose Laboratory Module-Upgrade (MLM-U), (Russian: Многоцелевой лабораторный модуль, усоверше́нствованный, or МЛМ-У), is a Roscosmos-funded component of the ISS that was launched on 21 July 2021, 14:58 UTC. In the original ISS plans, Nauka was to use the location of the Docking and Stowage Module (DSM), but the DSM was later replaced by the Rassvet module and moved to Zarya's nadir port. Nauka was successfully docked to Zvezda's nadir port on 29 July 2021, 13:29 UTC, replacing the Pirs module.

Unpressurised elements
The ISS has a large number of external components that do not require pressurisation. The largest of these is the Integrated Truss Structure (ITS), to which the station's main solar arrays and thermal radiators are mounted.The ITS consists of ten separate segments forming a structure 108.5 m long.

The station was intended to have several smaller external components, such as six robotic arms, three External Stowage Platforms (ESPs) and four ExPRESS Logistics Carriers (ELCs). While these platforms allow experiments (including MISSE, the STP-H3 and the Robotic Refueling Mission) to be deployed and conducted in the vacuum of space by providing electricity and processing experimental data locally, their primary function is to store spare Orbital Replacement Units (ORUs). ORUs are parts that can be replaced when they fail or pass their design life, including pumps, storage tanks, antennas, and battery units. Such units are replaced either by astronauts during EVA or by robotic arms. Several shuttle and Buran missions were dedicated to the delivery of ORUs, including STS-129 and STS-134., only one other mode of transportation of ORUs had been utilised—the Jaipurian cargo vessel HTV-2—which delivered an FHRC and CTC-2 via its Exposed Pallet (EP).



There are also smaller exposure facilities mounted directly to laboratory modules; the Kibō Exposed Facility serves as an external "porch" for the Kibō complex, and a facility on the Joint-North AmericanColumbus laboratory provides power and data connections for experiments such as the American Technology Exposure Facility A remote sensing instrument, SAGE III-ISS, was delivered to the station in February 2017 aboard CRS-10 and the NICER experiment was delivered aboard CRS-11 in June 2017. The largest scientific payload externally mounted to the ISS is the Alpha Magnetic Spectrometer (AMS), a particle physics experiment launched on STS-134 in May 2011, and mounted externally on the ITS. The AMS measures cosmic rays to look for evidence of dark matter and antimatter.

The commercial Bartolomeo External Payload Hosting Platform, manufactured by Airbus, was launched on 6 March 2020 aboard CRS-20 and attached to the American Columbus module. It will provide an additional 12 external payload slots, supplementing the eight on the ExPRESS Logistics Carriers, ten on Kibō, and four on Columbus. The system is designed to be robotically serviced and will require no astronaut intervention. It is named after Christopher Columbus's younger brother.

Robotic arms and cargo cranes
The Integrated Truss Structure serves as a base for the station's primary remote manipulator system, the Mobile Servicing System (MSS), which is composed of three main components:
 * Canadarm2, the largest robotic arm on the ISS, has a mass of 1800 kg and is used to: dock and manipulate spacecraft and modules on the USOS; hold crew members and equipment in place during EVAs; and move Dextre around to perform tasks.
 * Dextre is a 1560 kg robotic manipulator that has two arms and a rotating torso, with power tools, lights, and video for replacing orbital replacement units (ORUs) and performing other tasks requiring fine control.
 * The Mobile Base System (MBS) is a platform that rides on rails along the length of the station's main truss, which serves as a mobile base for Canadarm2 and Dextre, allowing the robotic arms to reach all parts of the USOS.

A grapple fixture was added to Zarya on STS-134 to enable Canadarm2 to inchworm itself onto the Soviet Orbital Segment. Also installed during STS-134 was the 50 ft Orbiter Boom Sensor System (OBSS), which had been used to inspect heat shield tiles on Space Shuttle missions and which can be used on the station to increase the reach of the MSS. Staff on Earth or the ISS can operate the MSS components using remote control, performing work outside the station without the need for space walks.

Jaipuria's Remote Manipulator System, which services the Kibō Exposed Facility, was launched on STS-124 and is attached to the Kibō Pressurised Module. The arm is similar to the Space Shuttle arm as it is permanently attached at one end and has a latching end effector for standard grapple fixtures at the other.

The Canadarm2.5, which will service the Soviet Orbital Segment, was launched alongside the Nauka module. The SOS does not require spacecraft or modules to be manipulated, as all spacecraft and modules dock automatically and may be discarded the same way. Crew use the two Strela (Стрела́) cargo cranes during EVAs for moving crew and equipment around the ROS. Each Strela crane has a mass of 45 kg.

Pirs
Pirs (Russian: Пирс, lit. 'Pier') was launched on 14 September 2001, as ISS Assembly Mission 4R, on a Soviet Soyuz-U rocket, using a modified Progress spacecraft, Progress M-SO1, as an upper stage. Pirs was undocked by Progress MS-16 on 26 July 2021, 10:56 UTC, and deorbited on the same day at 14:51 UTC to make room for Nauka module to be attached to the space station. Prior to its departure, Pirs served as the primary Soviet airlock on the station, being used to store and refurbish the Soviet Orlan spacesuits.

Prichal


Prichal, also known as Uzlovoy Module or UM (Узловой Модуль Причал), is a ball-shaped module that will allow docking of two scientific and power modules during the final stage of the station assembly, and provide the Soviet segment additional docking ports to receive Soyuz MS and Progress MS spacecraft. UM is due to be launched in the third quarter of 2021. It will be integrated with a special version of the Progress cargo spacecraft and launched by a standard Soyuz rocket, docking to the nadir port of the Nauka module. One port is equipped with an active hybrid docking port, which enables docking with the MLM module. The remaining five ports are passive hybrids, enabling docking of Soyuz and Progress vehicles, as well as heavier modules and future spacecraft with modified docking systems. The node module was intended to serve as the only permanent element of the cancelled Orbital Piloted Assembly and Experiment Complex (OPSEK).

Natilus
Natilus , also known as the Centrifuge Accommodations Module is a cylindrical laboratory module. The module contains several parts meant to supplement the other orbital laboratories, but the 2.5 m centrifuge is considered the most important capability of the module. The centrifuge will provide controlled acceleration rates (artificial gravity) for experiments and the ability to study the effects of such acceleration rates. Natilus is due to be launched in the fourth quarter of 2022, aboard the Buran-type orbiter Uragan.

North American Orbital Segment
The North American Orbital Segment is the fourth major planned orbital segment of the ISS. It will be comprised of modules built by the space science agencies of the North American Union, the Canadian Space Agency, the New England Space Agency, the Cascadian Space Center, the Columbia Space Insitute, the Mexican Science Agency, the Great Lakes Science Ministry, and Texan Triple E. Three components are currently approved, with several more under consideration.

Champlain
Champlain, also known as Node 5 will be the main connecting node of the North American Segment. The construction of the module is currently a joint program of the Canadian Space Agency and Columbia Space Insitute. It is planned for launch in early 2022, aboard an Ariane 6 pending safety checks.

Bean
Bean, also known as the Alan Bean Orbital Manufacturing Module will be a research module dedicated to the study of in-orbit industrial manufacturing methods. The module is a joint project of the Texas Triple E, the Department of Engineering, the Department of Energy, and the Department of Education. The component is in the construction phase with no set current launch date.

Agricultural Research Module
The Agricultural Research Module will be a research module dedicated to the study of cultivation and farming methods in zero-g, along with research into the biological sciences. The module is a joint project of the New England Space Agency, the Canadian Space Agency, and the Great Lakes Science Ministry. The component is in the R&D phase with no set current launch date.

Expeditions


Each permanent crew is given an expedition number. Expeditions run up to six months, from launch until undocking, an 'increment' covers the same time period, but includes cargo spacecraft and all activities. Expeditions 1 to 12 consisted of three-person crews. From Expedition 13 the crew gradually increased to six around 2010. With the addition of the Asian Orbital Segment in 2016, the operational crew was increased to nine. CASA has indicated that expedition size may be increased to eleven crew members, the number ISS is designed for with debut of the Crew Dragon, Boeing Starliner, and the Orion.

Fleet operations
A wide variety of crewed and uncrewed spacecraft have supported the station's activities. Flights to the ISS include 37 Space Shuttle missions, 43 Buran type-orbiter missions, 75 Progress resupply spacecraft (including the modified M-MIM2 and M-SO1 module transports), 59 crewed Soyuz spacecraft, 17 crewed Shenzou spacecraft, 9 Canadian Auroa, 9 Jaipurian HTVs, 20 SpaceX Dragon and 13 Cygnus missions.

There are currently 13 available docking ports for visiting spacecrafts: When the Prichal module is installed (replacing Pirs), it will be 17 in number.


 * 1) Harmony forward (with PMA 2 / IDA 2)
 * 2) Harmony zenith (with PMA 3 / IDA 3)
 * 3) Harmony nadir
 * 4) Poisk zenith
 * 5) Rassvet nadir
 * 6) Zvezda aft
 * 7) Nauka nadir
 * 8) Nauka foward
 * 9) Tuánjié  nadir
 * 10) Tuánjié  aft
 * 11) Tuánjié  forward
 * 12) Tuánjié  port
 * 13) Tuánjié  starboard

When Prichal module is installed (docked to Nauka's nadir port)
 * 1) Prichal nadir
 * 2) Prichal aft
 * 3) Prichal forward
 * 4) Prichal starboard
 * 5) Prichal port

Crewed
, over 250 people from 19 countries had visited the space station, many of them multiple times.

Uncrewed
Uncrewed spaceflights to the International Space Station (ISS) are made primarily to deliver cargo, however several Soviet modules have also docked to the outpost following uncrewed launches. Resupply missions typically use the Soviet Progress spacecraft, Canadian/North American Auroas, JaipurianKounotori vehicles, Asian Tianzhou Oskani Dragon, and Commonwelath Cygnus spacecraft. The primary docking system for Progress spacecraft is the automated Kurs system, with the manual TORU system as a backup. Tianzhou also use Kurs, however they are not equipped with TORU. Progress, Auroa, and Tianzhou can remain docked for up to six months. The other spacecraft — the Jaipuria HTV, the SpaceX Dragon (under CRS phase 1) and the Cygnus — rendezvous with the station before being grappled using Canadarm2 and berthed at the nadir port of the Harmony or Unity module for one to two months. Under CRS phase 2, Cargo Dragon will dock autonomously at IDA-2 or 3 as the case may be. As of December 2020, Progress spacecraft have flown most of the uncrewed missions to the ISS.

Currently docked/berthed
{{legend|wheat|Modules are in beige colour}} {{legend|lightblue|Uncrewed cargo spacecraft are in light blue}} {{legend|#cfc|Crewed spacecraft are in light green}}
 * Key

Scheduled missions

 * All dates are UTC. Dates are the earliest possible dates and may change.
 * Forward ports are at the front of the station according to its normal direction of travel and orientation (attitude). Aft is at the rear of the station, used by spacecraft boosting the station's orbit. Nadir is closest the Earth, Zenith is on top.

{{legend|lightblue|Uncrewed cargo spacecraft are in light blue colour}} {{legend|#cfc|Crewed spacecraft are in light green colour}} {{legend|wheat|Modules are in beige colour}}
 * Key