Orbital Piloted Assembly and Experiment Complex

Orbital Piloted Assembly and Experiment Complex

CG rendering of OPSEK
Station statistics
Crew	2 or more
Launch	2010s-20s
Launch pad	Baikonur Cosmodrome
Mass	over 100,000 kg when complete
Atmospheric pressure	1 atm
Periapsis altitude	370 to 450 km (planned)
Apoapsis altitude	370 to 450 km (planned)
Orbital inclination	70 degrees (planned)
Typical orbit altitude	370 to 450 km (planned)
Orbital speed	approx 28,000 km/h
Orbital period	approx 90 minutes
Orbits per day	approx 15
Days in orbit	0
Days occupied	0
No. of orbits	0

The Orbital Piloted Assembly and Experiment Complex (Template:Lang-ru, Orbitalnyj Pilotiruiemyj Ekspierimientalnyj Komplieks) (OPSEK) is a planned habitable artificial satellite in Low Earth orbit. It would be the 12th Russian space station launched. It is a third generation modular space station. The first ISS module that is planned to become part of OPSEK was launched in 2010. The space station would initially consist of modules taken from the Russian Orbital Segment of the International space station (ISS), which would be separated prior to the end of the ISS program. It is part of a deep-space network of space stations supporting manned exploration of the Solar system. Components of manned interplanetary ships are planned to be sent to the station for assembly before departing to Mars, the Moon, and possibly Saturn. Returning crew from these missions would recover on the station before returning to Earth.

Overview

Before the predicted decommissioning of the International Space Station in the late 2010s to 2020s, the Russian Federal Space Agency (Roskosmos) plans to detach some of its modules, such as the Multipurpose Laboratory Module (to be launched to the ISS in 2012), and use them as the basis for a new space station. Two Progress robotic ships will move the station from the ISS orbit at an inclination of 52 degrees to a 70 degrees inclined orbit. The main purpose of OPSEK would be to support eventual manned Mars missions.

On 17 June 2009, Roskosmos officially informed its ISS partner, the United States, about its intention to "build and prepare for operation the first elements of the orbital assembly and experimental piloted space complex by the end of the ISS life cycle."

According to the Russian manned spaceflight contractor RKK Energia, the new station must be able to perform the following tasks:

• Large spacecraft assembly
• Flight tests and launches
• Creating, servicing and completing inter-orbital tugs
• Providing medical and biological conditions required for the rehabilitation of interplanetary expedition crews after their return to Earth orbit.

Structure

OPSEK will follow the Salyut and Almaz series, Cosmos 557, and Mir as the 12th Russian space station launched. OPSEK is a third generation modular space station.

Other examples of modular station projects include the Soviet/Russian MIR, the International space station, Tiangong 3, and the Chinese space station. The first space station, Salyut 1, and other one-piece or "monolithic" first generation space stations, such as Salyut 2,3,4,5, DOS 2, Kosmos 557, Almaz, and NASA's Skylab stations, were not designed for re-supply. Generally, each crew had to depart the station to free the only docking port for the next crew to arrive. Skylab had more than one docking port but was not designed for resupply. Salyut 6 and 7 had more than one docking port and were designed to be resupplied routinely during crewed operation. Modular stations can allow the mission to be changed over time and new modules can be added or removed from the existing structure, allowing greater flexibility.

Separation from the ISS

Annotated image of the International space station's Russian Orbital Segment configuration as of 2011

Space stations require orbital station-keeping capabilities to counter the effects of atmospheric drag. Reboosting the orbit of the ISS, which descends 25 km per year due to friction with the thin atmosphere at 400 km, is done by the Russian orbital segment (ROS) or a Russian or European ship docked to that section, and formerly was also done by the U.S. Space Shuttle. Life support facilities such as atmosphere control, the water supply system, the food supply facilities, the sanitation and hygiene equipment, and fire detection and suppression equipment are required to support a crew. The ROS life support systems are contained in the Service Module Zvezda. Some of these systems are supplemented by equipment in the USOS. The MLM Nauka laboratory has a complete set of life support systems. The separation of the ROS from the ISS would result in the loss of the United states orbital segment.

Modules

Expected Russian Orbital Segment modules around the time of OPSEK separation (2020 or later) arranged by launch dates:

• 2000, Zvezda (DOS-8) - potential part of OPSEK
• 2009, Poisk (MRM-2) - potential part of OPSEK

Poisk (Template:Lang-ru; lit. Search), also known as the Mini-Research Module 2 (MRM 2), [Малый исследовательский модуль 2] Error: {{Lang}}: text has italic markup (help), or МИМ 2. Poisk is a Russian airlock module with two identical hatches. An outward opening hatch on the MIR space station failed after it swung open too fast after unlatching, due to a small amount of air pressure remaining in the airlock. A different entry was used, and the hatch repaired. All EVA hatches on the ISS and OPSEK open inwards and are pressure sealing. Its precedessor, Pirs, is used to store, service, and refurbish Russian Orlan suits. The outermost docking ports on both airlocks allow docking of Soyuz and Progress spacecraft, and the automatic transfer of propellants to and from storage on the station.

Rassvet, left of center with the Russian science airlock temporarily stored on its side

• 2010, Rassvet (MRM-1) - to form part of OPSEK

Rassvet (Template:Lang-ru; lit. "dawn"), also known as the Mini-Research Module 1 (MRM-1) (Template:Lang-ru, МИМ 1) and formerly known as the Docking Cargo Module (DCM), is similar in design 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. Rassvet was launched with the Russian Nauka Laboratory's Experiments airlock temporarily attached to it, and spare parts for the European Robotic Arm. Both will be part of OPSEK.

• 2012, Nauka (FGB-2) - to form part of OPSEK

Nauka (Template:Lang-ru; lit. Science), also known as the Multipurpose Laboratory Module (MLM) or FGB-2, (Russian: Многофункциональный лабораторный модуль, or МЛМ), is the major Russian laboratory module. This module will be separated from the ISS before de-orbit with support modules to become the OPSEK space station. It contains an additional set of life support systems and orientation control. Nauka's mission has changed over time; during the mid 1990s it was intended as a backup for the FGB, and later as a universal docking module (UDM). Its docking ports will be able to support automatic docking of both spacecraft, additional modules and fuel transfer. Prior to the arrival of the MLM, a Progress robotic spacecraft will dock with the ISS PIRS module, depart with that module, and both will be discarded. Nauka will then use its own engines to attach itself to the ROS in 2012. The European Robotic Arm, which will service the Russian Orbital Segment, will be launched alongside the MLM in 2012.

Computer generated image of the ROS after Nauka docking.

• 2013, Node Module - to form part of OPSEK

Node Module (UM)/(NM) This 4-ton ball shaped module will support the docking of two scientific and power modules during the final stage of the station assembly and provide the Russian segment additional docking ports to receive Soyuz TMA (transportation modified anthropometric) and Progress M spacecraft. NM is to be incorporated into the ISS in 2012. It will be integrated with a special version of the Progress cargo ship and launched by a standard Soyuz rocket. The Progress would use its own propulsion and flight control system to deliver and dock the Node Module to the nadir (Earth-facing) docking port of the Nauka MLM/FGB-2 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. More importantly, the node module was conceived to serve as the only permanent element of OPSEK. Equipped with six docking ports, the Node Module would serve as a single permanent core of the future station with all other modules coming and going as their life span and mission required. This would be a progression beyond the ISS and Russia's modular MIR space station, which are in turn more advanced than early monolithic first generation stations such as Skylab and early Salyut and Almaz stations.

• 2014, Science-Power Module-1 - to form part of OPSEK
• 2015, Science-Power Module-2 - to form part of OPSEK

Safety

Orbital debris

Main article: space debris

OPSEK will be operated in Low Earth Orbit, 400 kilometers above the Earth at an orbital inclination of 70 degrees, in the center of the Earth's Thermosphere. At this altitude there is a variety of space debris, consisting of many different objects including entire spent rocket stages, dead satellites, explosion fragments (including materials from anti-satellite weapon tests), paint flakes, slag from solid rocket motors, coolant released by RORSAT nuclear powered satellites, and some of the 750,000,000 small needles from the American military Project West Ford. These objects, in addition to natural micrometeoroids, are a significant threat. Large objects could destroy the station, but are less of a threat as their orbits can be predicted. Objects too small to be detected by optical and radar instruments, from approximately 1 cm down to microscopic size, number in the trillions. Despite their small size, some of these objects are still a threat because of their kinetic energy and direction in relation to the station. Spacesuits of spacewalking crew could puncture, causing exposure to vacuum.

Space debris objects are tracked remotely from the ground, and the station crew can be notified. This allows for a Debris Avoidance Manoeuvre (DAM) to be conducted, which uses thrusters on station to change orbital velocity and altitude, avoiding the debris. DAMs will take place if computational models show that the debris will approach within a certain threat distance. Usually the orbit will be raised, saving fuel, as the station's orbit must be boosted periodically to counter the effects of atmospheric drag. If a threat from orbital debris is identified too late for a DAM to be safely conducted, the station crew closes all the hatches aboard the station and retreat into their Soyuz spacecraft, so that they would be able to evacuate in the event of damage from the debris. Micrometeorite shielding is incorporated into the station to protect pressurised sections and critical systems. The type and thickness of these panels varies depending upon their predicted exposure to damage.

Radiation

Main articles: Coronal mass ejection and Aurora (astronomy)

Stations in low earth orbit are partially protected from the space environment by the Earth's magnetic field. From an average distance of about 70,000 km, depending on Solar activity, the magnetosphere begins to deflect solar wind around the Earth and space stations in orbit. However, solar flares are still a hazard to the crew, who may receive only a few minutes warning. The crew of the ISS took shelter as a precaution in 2005 in a more heavily shielded part of that station designed for this purpose during the initial 'proton storm' of an X-3 class solar flare. Without the limited protection of the Earth's magnetosphere, deep space missions such as China's planned manned mission to Mars are especially at risk.

Video of the Aurora Australis taken by the crew of the ISS on an ascending pass from south of Madagascar to just north of Australia over the Indian Ocean.

Subatomic charged particles, primarily protons from cosmic rays and solar wind, are normally absorbed by the Earth's atmosphere. When they interact in sufficient quantity their effect becomes visible to the naked eye in a phenomenon called an aurora. Without the protection of the Earth's atmosphere, which absorbs this radiation, station crews are exposed to about 1 millisievert each day, which is about the same as someone would get in a year on Earth, from natural sources. This results in a higher risk of crew members developing cancer. Radiation can penetrate living tissue and damage DNA, in particular the chromosomes of lymphocytes. These cells are central to the immune system, and so any damage to them could contribute to the lowered immunity experienced by crew. Radiation has also been linked to a higher incidence of cataracts in astronauts. Protective shielding and protective drugs may lower the risks to an acceptable level.

The radiation levels experienced on the ISS are about 5 times greater than those experienced by airline passengers and crew. The Earth's electromagnetic field provides almost the same level of protection against solar and other radiation in low Earth orbit as in the stratosphere. Airline passengers, however, experience this level of radiation for no more than 15 hours for the longest intercontinental flights. For example, on a 12 hour flight an airline passenger would experience 0.1 millisievert of radiation, or a rate of 0.2 millisieverts per day, only 1/5 the rate experienced by an astronaut in LEO.

External links

• OPSEK information page
• Presentation, by Head of Russian Federal Space Agency, June 17, 2009

Live viewing

See List of satellite trackers

• Heavens-above Position on globe and simple instructions to see the ISS/OPSEK with no equipment.
• n2yo Position on scalable map with optional footprint.
• Calsky for astronomers and astrophotographers. Prediction for aurora, ISS/OPSEK passes, occultations and transits.

Youtube

• Feature Film First Orbit the story of the first man in space.
• ISS: Video (01:02): Earth (Time-Lapse)
• ISS: Video (00:27): Earth and Auroras (Time-Lapse)
• Russian space agency youtube channel

Image galleries

• Thierry Legault's website Astrophotograper
• Lana Sator's unescorted tour of the space station engine factory, Energomash.
• Commons
• RSC Energia: Science Research on ISS Russian Segment

Space Agency websites

 Europe,  Russia (Energia),  Russia (Federal),