On the ISS, a module or compartment that permits movement of astronauts or equipment between the Space Station and open space. When the internal hatch is closed, the airlock is isolated from the rest of the Station; the atmosphere is pumped out or vented and then the external hatch can be opened. There are four airlocks on the ISS: one for equipment alone, two for EVAs in Russian spacesuits, and one for EVAs in American spacesuits. (The latter is indicated in this book as Airlock with a capital letter.)
APFR (Articulating Portable Foot Restraint)
A portable device for securing an astronaut’s feet during an EVA so that the hands are left free to work. It can be fixed to the robotic arm of the ISS or to designated interfaces along the Station. It has three independent joints that allow the user to find the optimal orientation.
ARED (Advanced Resistive Exercise Device)
A machine for resistance training on the ISS, which allows users to perform the most common weight-lifting exercises in weightlessness.
The orientation in space of a vehicle, astronaut or object.
ATV (Automated Transfer Vehicle)
An ISS cargo spacecraft with automatic docking capability, developed by ESA. ATV carried out five cargo missions between 2008 and 2015.
Reserve crew for a space mission. They receive the same training as the prime crew and substitute for them if one or all members of the prime crew are unable to carry out the mission.
Refers to a vehicle’s non-guided, passive movement through the air under the effect of gravity and aerodynamic forces. The Soyuz spacecraft is capable of making a ballistic re-entry in an emergency.
A unit for measuring pressure. The atmospheric pressure at sea level is approximately 1 bar.
BDC (Baseline Data Collection)
Sample collection and baseline biomedical measurements taken by researchers on astronauts before and after a mission. The BDC allows researchers to evaluate the results of a scientific experiment by comparing in-flight data with data obtained pre- and post-flight.
A small supply of food chosen by each ISS astronaut in line with their personal preferences and set regulations.
Usually refers to auxiliary engines that increase the thrust of a rocket during the first phase of its ascent.
A semi-rigid tool used during an EVA to anchor the astronaut to the workplace and for attaching objects to the suit for transport. It’s an adjustable arm consisting of a series of metal spheres on a guide. By varying the tension, the arm can be tightened or loosened. One end is fixed to the mini-workstation on the suit, and the other is free and can be attached to handrails or objects as needed for carrying.
The name for the NASA Mission Control Center position in Houston responsible for speaking to the astronauts on Space-to-Ground radio.
CAVES (Cooperative Adventure for Valuing and Exercising Human Behaviour and Performance Skills)
ESA training course for astronauts conducted in a space-analogue cave environment over several days, training them to carry out exploration activities and allowing them to develop and exercise efficiency, cooperation and risk management as part of international crews.
CEVIS (Cycle Ergometer with Vibration Isolation and Stabilization)
Stationary bicycle for cardiovascular training on the ISS.
Training technique borrowed from the aeronautics world, where it is generally used by pilots preparing to execute in-flight procedures and operations. It consists of mentally executing a planned sequence of actions and checks.
Class name for the group of American, Japanese and Canadian astronauts who took basic training together in Houston starting in 2009. The name suggests ‘goofballs’, and was jokingly given to them in a play on words when they suggested ‘Chimps’ instead.
Psychological support package sent to astronauts on mission in consultation with their families. It can contain food, clothes, gifts, letters, photos, books, personal effects or other objects that contribute to maintaining close ties and overall emotional well-being.
ISS cargo spacecraft developed by the American company Northrop Grumman Innovation Systems (originally Orbital ATK). It has been flying cargo on behalf of NASA since 2013 within the scope of a programme for supplying commercial transport services to the ISS.
DCM (Display and Control Module)
Control panel attached to the chest of the EMU suit which allows the astronaut to monitor the telemetry and send commands.
A procedure for lowering the orbit of the ISS through engine ignition on the Station or on a docked vehicle. The reboost – a procedure for raising the orbit – is more commonly effected.
The part of the Soyuz spacecraft in which the astronauts travel during the launch, the re-entry and other critical phases of the flight. Bell-shaped and equipped with a heat shield, it is the only part that returns to Earth with the crew.
Aerial combat, usually at close quarters.
An EMU suit support that allows astronauts, during their training in the pool, to put the suit on without supporting its weight. It is attached to a platform which is lifted by crane while the astronaut is in the suit and lowered in the pool. The two analogous structures in the ISS Airlock have the same name.
DPC (Daily Planning Conference)
Meeting held via radio between ISS astronauts and mission control centres. Each workday there are two DPCs, one at the beginning and one at the end of activities.
ISS cargo spacecraft developed by the American firm SpaceX. It has carried cargo on behalf of NASA since 2012 within the scope of a programme for supplying commercial transport services to the ISS.
EMU (Extravehicular Mobility Unit)
A NASA pressure suit for extravehicular activities from the American Airlock.
Portion of space in which an astronaut in a pressure suit can work efficiently with the hands (work envelope); or the portion of space in which it’s possible for the robotic arm to activate its capture mechanism to capture a cargo vehicle (capture envelope).
A robotic arm for the ISS, developed by ESA and installed on the outside of the MLM module.
Name for the position at the Columbus Control Centre, or Col-CC, responsible for speaking with the astronauts on Space-to-Ground radio, usually about activities in the ESA Columbus module.
Extra Vehicular Activity or spacewalk: activity executed outside a space vehicle by a crew member wearing a pressurized spacesuit. On the ISS the activity is usually concerned with installation or maintenance.
A trench or large hole located under the launchpad to guide the rocket exhaust away from the pad at lift-off.
A redistribution of bodily fluids commonly caused by weightlessness.
Component of the EMU pressure suit which ensures the circulation of air and water for cooling and removes condensate.
Flight mode in which a spacecraft does not actively control its own attitude and position, and therefore does not react to external forces changing those.
Here it refers to a unit of measurement for the perceived weight felt in the centrifuge or inside an accelerating spacecraft. 1 G corresponds to a person’s or object’s weight on the Earth’s surface.
Cloth headgear with integrated audio (earphones and microphone) for radio communication. It’s worn by astronauts under the helmet of the Sokol suit.
G-LOC (G-force Induced Loss of Consciousness)
Temporary loss of consciousness caused by the flow of blood away from the brain and induced by intense acceleration in the head-to-foot direction typical of aerobatic manoeuvring or aerial combat.
Pre-breathe protocol adopted for use in the NASA Airlock on the ISS in preparation for an EVA.
Describes the role of an astronaut who manages the operations preceding and following an EVA in the EMU suit, such as suit donning/doffing, pre-breathe and depressurization/repressurization of the Airlock.
Name for the position at the Control Centre of the Japanese Space Agency responsible for speaking with the astronauts on Space-to-Ground radio, usually about activities in the Japanese module JEM.
Propulsive system worn on the back and usually powered by cold gas thrusters; for example, the SAFER on the EMU suit for EVAs.
Navigation system for approach and automatic docking of the Soyuz and Progress spacecraft on the Russian segment of the ISS.
LCVG (Liquid Cooling and Ventilation Garment)
Garment worn by astronauts under the EMU suit for EVAs. Contains integrated ventilation tubes and around 80 metres of smaller tubes to circulate cooling water.
A check carried out on a spacesuit or a module whose pressure is different from the surrounding pressure in order to verify that any air or gas leaks are within acceptable limits.
An imaginary line that joins a space vehicle in orbit with the centre of the Earth, assuming for simplicity’s sake that the Earth is a perfect homogeneous sphere.
MCOP (Multilateral Crew Operations Panel)
Panel composed of representatives of the ISS partner Agencies and concerned with crew matters such as selection criteria, certification, training and mission assignment.
Condition of weightlessness induced by free fall. The term highlights the existence of small residual accelerations due to the finite extension of the concerned system and other disturbances.
Unit of pressure measurement commonly used on the Soyuz and the ISS. The atmospheric pressure at sea level is around 760 millimetres of mercury.
Tool support fixed to the EMU pressure suit for EVAs. It is a metallic structure secured to the front part of the suit at chest level.
MLM (Multifunctional Laboratory Module)
Russian laboratory module on the ISS which will be used to conduct scientific experiments, provide crew services and host the external European Robotic Arm (ERA).
NBL (Neutral Buoyancy Laboratory)
NASA training facility with a large pool in which astronauts wearing the EMU suit train for EVAs. Contains a real-size model of the non-Russian modules of the ISS.
NEEMO (NASA Extreme Environment Mission Operations)
NASA programme that sends groups of astronauts, engineers and scientists to an underwater laboratory for missions of up to three weeks. Experiments, technology tests and simulations of space operations are carried out there.
Mixture of nitrogen and oxygen, containing less nitrogen and more oxygen than normal air. It is used in scuba-diving as well as during EVA training underwater, to reduce the risk of decompression sickness.
Refers to normal behaviour for spacecraft and equipment, or an event that goes according to plan, without breakdowns or emergencies.
A habitable part of the Soyuz spacecraft which includes the docking system and the hatch that provides access to the ISS. It is jettisoned shortly before re-entry into the atmosphere.
Pressure suit for EVAs from the Russian airlocks SO-1 and MIM-2.
Can be intuitively understood as a description of how much of a particular gas is present in a gas mixture. More precisely, it is the pressure that each of the gases in a mixture would exert if it occupied the entire volume of that gas mixture at the same temperature.
Name for the position at the Payload Operations Centre in Huntsville responsible for speaking with the astronauts on Space-to-Ground radio, usually about NASA experiments.
Here, scientific research activities and technological development conducted on board the ISS.
Battery-operated screwdriver with a pistol grip used by astronauts in their extravehicular activities in the EMU.
During rendezvous, the phase angle is the angle between the position of an approaching Soyuz and that of the ISS measured in the Station’s orbital plane and with the vertex at the Earth’s centre. Assuming that the vehicles are on the same orbit, if the phase angle is close to 0°, the two are close; if it is 180°, then they are diametrically opposed. Intuitively, it is an indication of the distance between vehicles along the orbital arc that joins them.
A hot, ionized gas in which most of the electrons are separated from their respective nuclei.
POGO (Partial Gravity Simulator)
A mechanical and pneumatic suspension system used by NASA to train astronauts for EVAs. It partially balances the weight of the subject, allowing them to rotate and to move vertically and horizontally, thus simulating some aspects of weightlessness.
Process that reduces the amount of nitrogen present in body tissues. It’s carried out in preparation for an EVA in order to diminish the risk of decompression sickness owing to the difference between the pressure in the spacecraft and the operating pressure of the suit.
Training simulation for operations that precede and follow an EVA in the EMU suit, such as suit donning/doffing, pre-breathe and depressurization/repressurization of the Airlock.
In the ISS rotation system, a crew that no longer serves as back-up for a launch preceding their own. They are usually in the final six months of training.
Unit of pressure measurement commonly used in the English-speaking world. The atmospheric pressure at sea level is around 15 psi.
In engineering, the duplication of components or critical system functions to increase reliability through the presence of reserve elements. On a spacecraft, it can also be achieved by allowing the crew to take over manual control in case of automatic system malfunction, or by training more than one crew member to carry out the same duty.
The speed of one vehicle relative to another.
A series of manoeuvres that bring a spacecraft into the vicinity of a second vehicle.
Transportation of a rocket from the assembly building to the launchpad.
SAFER (Simplified Aid For EVA Rescue)
Emergency propulsion system affixed to the EMU suit. Allows an astronaut carrying out an EVA to return to the Space Station in the event of accidental loss of physical contact with the ISS structure.
Non-habitable part of the Soyuz, with the main engine and solar panels. It is different from the Service Module (in this book with capital letters), which is a module of the Russian segment of the ISS.
Radio communication channels used by astronauts to speak from the ISS to the Mission Control Centres.
Cloth headgear with integrated audio (earphones and microphone) for radio communication, worn by astronauts under the EMU suit helmet. So named because it resembles the aviator cap Snoopy wears in the Peanuts cartoons by Charles Schulz.
Pressure suit worn by astronauts flying in the Russian spacecraft Soyuz. An emergency suit, it is designed to sustain an astronaut’s life in the event of atmospheric loss in the cabin and cannot be used in space outside a spacecraft.
Russian spacecraft for crew missions in Earth orbit, with a maximum crew of three persons; or Russian rocket fuelled by kerosene and liquid oxygen which launches the Soyuz and Progress vehicles.
SSRMS (Space Station Remote Manipulator System)
Canadian-made robotic arm on the ISS, also called Canadarm 2. It is used for the construction and maintenance of the Station, to transport equipment along the structure, to support astronauts in EVAs and for the capture of the cargo vehicles HTV, Dragon and Cygnus.
Treadmill on the ISS.
Manoeuvre for approaching and coupling the robotic arm SSRMS to a spacecraft in free flight in order to capture it and attach it to the ISS.
Table summarizing pre-launch trips to the various international training centres for all crews assigned to a mission on the ISS. It is periodically updated by the schedulers in the partner space agencies.
Large lattice structure on the ISS to which non-pressurized components are fixed, such as solar panels, radiators and pumps for the cooling system and storage platforms for spare parts.
Russian Mission Control Centre responsible for Soyuz and Progress operations and for the Russian segment of the ISS.
A bundle of cables and flexible tubes that connect a rocket to the infrastructure of the launchpad and ensure electrical, propellant and gas supplies, data transmission and audio communication. Also, a bundle of cables and hoses that provide breathing gas, cooling water and radio communication to an EVA suit when training underwater.
Universal Time Coordinated: the international standard for indicating time; it corresponds to Greenwich Mean Time.
A room from which air has been extracted to create a vacuum or greatly reduced pressure. During ISS training, it’s used to simulate realistic conditions for the activities in the airlock before and after a spacewalk and for testing the Sokol suit in pressurized conditions.
VOIP (Voice Over Internet Protocol)
A telephony system that uses the internet or similar web technology. Skype is one example.
The process of attaching weights and floaters to an Orlan or an EMU suit to achieve neutral buoyancy and neutral attitude.