Technology Demonstration

A Researcher’s Guide to:

National Aeronautics and Space Administration
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This International Space Station (ISS) Researcher’s Guide is published by the 

NASA ISS Research Integration Office.

Authors:

Ousmane Diallo, Ph.D. Brandon Redell, Ph.D.

Lakita Lowe Thilini Schlesinger

Ken Neiss Jennifer Scott Williams

Henry Orosco

Executive Editor: Bryan Dansberry, Ed.D.

Technical Editor: Carrie Gilder

Designer: Cory Duke

Cover art: Chris Getteau

Published: June 2013

Revised: July 2022

Cover and back cover:

a. Over a background of Earth cloud masks, photos are from left to right, top to bottom: 

• ESA (European Space Agency) Astronaut Alexander Gerst participates in the Grip study in the 

Columbus Module. Grip is an ESA-sponsored experiment researching adaptation of the nervous 

system to microgravity.

• View of Space Test Program - Houston #7 (STP-H7) taken by External High Definition Camera 3 

(EHDC3) during Expedition 66. The STP-H platform hosts multiple external payloads from various 

institutions.

• (Two panes) NASA spacewalker Shane Kimbrough carries the second roll out solar array toward 

the International Space Station’s Port-6 truss structure for installation. 

• NASA astronaut and Expedition 59 Flight Engineer Christina Koch wears a virtual reality headset 

during Virtual Reality Training (VRT) on orbit for refamiliarization training prior to an EVA.

• The Kibo laboratory module from the Japan Aerospace Exploration Agency, comprised of a 

pressurized module and exposed facility, a logistics module, a remote manipulator system and 

an inter-orbit communication system unit, is pictured as the ISS orbits over the southern Pacific 

Ocean east of New Zealand.

• View of an External High Definition Camera (EHDC) newly installed at Camera Port 9 (CP9) on the 

P1 Truss during Extravehicular Activity 37.

• Deployment of the AQT-D CubeSat from the JEM Small Satellite Orbital Deployer aboard the 

ISS. AQua Thruster-Demonstrator (AQT-D) is a 3U CubeSat demonstration of a water resistojet 

propulsion system developed by The University of Tokyo.

Back cover:

b. NASA and Made in Space are collaborating to better understand the behavior of 3D printing in 

zero gravity and recently launched a polymer recycler to the ISS. Astronauts test the processing of 

raw plastic materials and convert plastic packaging and trash into usable 3D printing feedstock for 

3D-printed parts and tools.

c. Several tiny satellites are featured in this image photographed by an Expedition 33 crew member 

on the ISS. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital 

Deployer attached to the Japanese module’s robotic arm. A portion of the station’s solar array panels 

and a blue and white part of Earth provide the backdrop for the scene.
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The mission of the International Space Station (ISS) Program is to advance 

science and technology research, expand human knowledge, inspire and 

educate the next generation, foster the commercial development of space 

and demonstrate capabilities to enable future exploration missions beyond 

low Earth orbit (LEO).

To execute this mission — specifically, technology advancements — the 

ISS Program is using the space station as a test bed to demonstrate 

operational techniques and capabilities, and demonstrate technologies and 

advanced systems that benefit space science capabilities and human and 

robotic exploration beyond LEO. Working with the international exploration 

community, the Global Exploration Roadmap was developed to provide an 

internationally, phased approach defining capabilities that will be needed 

for future exploration. Demonstration of these advanced capabilities is a 

primary objective of the ISS Program mission.

This booklet has been developed to provide prospective technology and 

advanced system developers the information that will aid in the formulation 

of demonstration concepts and as an introduction of station capabilities, 

characteristics and processes.

The following pages begin 

by describing the technology 

development areas of greatest 

interest to the National 

Aeronautics and Space 

Administration (NASA) followed 

by descriptions of ISS interfaces 

and the manifesting process. 

Finally, points of contact are 

identified before a description of 

the processes and capabilities 

that are available to selected and 

manifested payloads.

The Lab is Open

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The Microbial Aerosol Tethering on Innovative Surfaces in the 

International Space Station (MATISS) experiment investigates 

the antibacterial properties of materials in space to see if future 

spacecraft could be made easier to clean. The experiment 

aims to understand the mechanisms of attachment of biofilms 

in microgravity conditions.
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The Lab is Open 3

ISS Technology Demonstration Program 6

Overview 6

Technology Readiness Level Advancement 6

Propulsion Systems 7

Flight Computing and Avionics 7

Space Power and Energy Storage 8

Robotics Systems 8

Communication and Navigation 9

Human Health, Life Support, and Habitation Systems 9

Exploration Destination Systems 10

Sensors and Instruments 10

Entry, Descent, and Landing Systems 10

Autonomous Systems 11

Materials, Structures, Mechanical Systems, and Manufacturing 11

Thermal Management Systems 12

Guidance, Navigation, and Control (GN&C) 12

ISS Accommodations 13

Internal 13

Expedite the Processing of Experiments for Space Station (EXPRESS) Racks 13

Station-to-Internal-Facility Rack Resources 15

Aisle Deployed Payloads 15

Nanoracks Nanode and Nanolabs 16

ISS Cold Stowage 17

Other Internal Tools 20

Airlocks 20

Japanese Experiment Module (JEM) Airlock 20

Bishop Airlock 21

Accommodations for Hosted Payloads 23

Accommodations for Microgravity Research 24

External 25

EXPRESS Logistics Carrier (ELC) 25

ISS Attach Sites 26

Columbus Exposed Facility (EF) 27

Japanese Experiment Module - Exposed Facility (JEM-EF) 27

NanoRacks External Platform (NREP) 28

Table of Contents
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Robotic capabilities 29

Mobile Servicing System 29

Japanese Experiment Module Robotic Manipulator System 30

Access to the External Environment 30

Robotic Interfaces 30

Special Considerations 31

Deployable Small Satellites 31

Software and Avionics, ISS Command and Data Handling 33

Health and Status Data 33

Broadcast Ancillary Data 33

Unique Ancillary Data 33

ISS Data Interfaces 34

Data Downlink Availability Downlink and Storage 35

Command/Data Latency 36

Payload Software and Displays 37

Telescience Resource Kit – Payload Operations Interface 37

ISS Characteristics 38

Internal Atmosphere 38

Orbit Characteristics 38

Guidance, Navigation, and Control Characteristics 39

Microgravity Environment 40

External Contamination 40

Transportation to ISS 41

ISS Cargo Vehicles 41

Funding, Developing, and Launching Research to ISS 43

ISS U.S. National Lab 43

Other Government Agencies 44

International Funding Sources 44

ISS Commercial 45

Working with NASA 46

Acronyms 47
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Overview

The ISS Program provides an infrastructure capable of demonstrating prototypes 

and systems that may advance spaceflight technology readiness. The space station, 

the in-orbit crew, the launch and return vehicles, and the operation control centers 

are all supporting the demonstration of advanced systems and operational concepts 

that will be needed for future exploration missions.

The ISS is the only long-duration platform available in the relevant space 

environment with an integrated space systems architecture that can be used to 

demonstrate advanced technologies and operations concepts. Working in close 

cooperation with the exploration community, the ISS Program enables technology 

and systems investigations in support of future exploration endeavors. 

The ISS Program aims to demonstrate many types of technologies on the space 

station where they can be evaluated without significant risk to crew or vehicle in 

order to accelerate development and reduce risks for future exploration missions.

Technology Readiness Level Advancement

The ISS Laboratory is available to conduct research and/or engineering 

investigations to advance Technology Readiness Levels (TRL) by demonstrating 

system performance in the unique space environment offered by station or its 

visiting vehicles. Additionally, station-based demonstrations support proofing 

concepts of operations, training, crew interfaces, and logistics as well as the 

ISS Technology 

Demonstration Program
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maintainability and reliability of payloads. Performing these demonstrations on the 

space station provides an opportunity to obtain operational knowledge in a relevant 

environment without the added costs and risk associated with integrating a new 

technology or advanced system into an operational system.

In 2020, NASA identified 17 exploration technology areas of interest to enable 

future space missions and support commercial air travel. Of these 17, ISS can 

serve as a Technical Demonstation test bed for the following 13 technology areas. 

Details of exploration and technology needs are documented in the document 

2020 NASA Technology Taxonomy.

Propulsion Systems

Systems for in-space propulsion can benefit 

from in-space demonstration by gaining 

operational run time in the microgravity, 

vacuum and thermal environments of 

space while gaining experience in fuel 

flow management and performance. 

Demonstrations providing integrated system 

operations or subsystem investigations 

demonstrating supporting elements of a 

system can be performed.

If scaled to not adversely impact ISS, in-space 

propulsion systems can be demonstrated 

on the space station, potentially on visiting 

vehicles or deployed free fliers.

Flight Computing and Avionics

Flight computing and Avionics is a broad area that covers unique electronics 

and computing hardware when applied to flight systems. On-board ISS, flight 

computing and avionics systems can be exposed to the harsh environment of 

ESA Astronaut Thomas Pesquet closes out the Fluidics study. 

ESA’s fluid physics investigation may lead to the development of 

better fuel systems for satellites and provide for longer satellite 

lifetime by better managing use of fuel for maneuvering.
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space to assess the effects of such factors 

as extreme heat and cold, high-energy 

radiation, extreme vacuum, and space debris 

impact. The knowledge gained through 

technology demonstrations can inform the 

development of future computing systems 

for deep space exploration. 

Avionics systems and subsystems are the 

building blocks for vehicles and spacecraft 

that implement key functionality for 

Command and Data Handling, Data 

Acquisitions, and other essential functions 

for NASA missions.

Space Power and Energy Storage

Solar array and solar cell demonstra-tions 

in space are important because they allow 

developers to test device performance 

without the solar filtering and diffusion 

caused by the atmosphere. At the same 

time, they provide the appropriate thermal 

and dynamic loading conditions for an 

implemented system.

Fuel cells and other systems that operate 

with fluids, especially two-phased fluids, 

benefit from demonstrating performance in 

the microgravity environment.

Robotics Systems

Robotic systems operating in and around a spacecraft, 

with or without crew-robot interaction, demonstrate 

performance and operational concepts of robotic systems 

in the crewed and uncrewed spacecraft environments.

Deployment of the NanoRacks-Remove Debris 

Satellite from the International Space Station (ISS) 

using the NanoRacks Kaber MicroSat Deployer. 

NanoRacks-Remove Debris aims to demonstrate key 

technologies for Active Debris Removal to reduce the 

risks presented by space debris.

The Roll-Out Solar Array (ROSA) is a new type of solar 

panel that rolls open in space like a party favor and is 

more compact than current rigid panel designs. 

NASA astronaut Megan McArthur poses with the Astrobee robotic free-flyers in 

support of the Kibo Robot Programming Challenge (Robo-Pro Challenge). The 

Kibo-RPC allows students to create programs to control Astrobee, a free-flying 

robot aboard the ISS.
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Communication and Navigation

Communication systems can use the space 

station infrastructure to demonstrate 

delay tolerance and eliminate space 

communication architecture bottlenecks, 

thus increasing throughput of the 

integrated systems.

Navigation systems can be demonstrated on 

ISS, comparing system performance to the 

spacecraft’s known position. Advanced or 

automated rendezvous and docking systems 

can be demonstrated with ISS and visiting vehicles or dedicated free fliers. (See also 

Guidance, Navigation, and Control)

Human Health, Life Support, and Habitation Systems

The job of maintaining a habitable 

environment for the crew over the duration 

of a human spaceflight mission is performed 

by Environmental Control & Life Support 

Systems (ECLSS). Living in space for long 

durations with little or no resupply from 

Earth is a fundamental capability that 

is being matured through day-to-day 

operations on the only platform capable 

of that task – ISS. For long-duration 

exploration beyond LEO, spacecraft systems 

must provide a stable, self-contained microenvironment around the clock by revitalizing 

the air, collectingand processing wastewater 

streams to recover and provide safe drinking 

and hygiene water for the crew, and managing solid wastes (metabolic and trash). 

ISS presents the opportunity to perform limited upgrades to the current systems to 

increase operational availability and reduce system mass, consumables and power 

needs beyond the current capability. At the same time, ISS provides a directly relevant 

operating environment to perform demonstrations of technologies and prototype 

systems to reach capabilities necessary to enable an exploration-class mission. 

SCAN Testbed installed on ELC 4 nadir side of the ISS.

The Capillary Structures for Exploration Life Support 

investigation studies water recycling and carbon 

dioxide removal using structures of specific shapes 

to manage fluid and gas mixtures, benefiting future 

efforts to design lightweight, more reliable life support 

systems for future space missions.
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Operational demonstrations aboard ISS will ensure that the ECLSS needed for 

exploration beyond LEO has been verified properly to keep the crew alive and safe 

for more than a year away from Earth.

Exploration Destination Systems

Human Exploration Systems are exploration-specific capabilities that do not 

clearly fall into other technology categories. As such, the technologies in this area 

are diverse and expansive. Many of these technologies are related to extravehicular 

activity (EVA), or spacewalks, and general habitation. These systems can benefit 

from the microgravity environment and utilization within the operation of the 

station-habitable environment.

Sensors and Instruments

As advances in scientific technology enable more 

capable science and sensor systems, prototype 

systems can be demonstrated on ISS to evaluate 

performance in the space environment and in 

relevant conditions. On ISS, these systems can 

be evaluated by the in-orbit crew or within 

the existing station commanding and data 

infrastructure, such that confidence can be gained 

and risks reduced in the system before it is used 

on a dedicated science mission. Additionally, 

science system demonstrations can be used to 

evaluate and assist in choosing among systems that 

are under consideration.

Entry, Descent, and Landing Systems 

ISS visiting vehicles re-enter Earth’s 

atmosphere following station-docked missions. 

There are several methods to deploy small 

The Biomolecule Sequencer for the BEST 

experiment demonstrated the feasibility of 

DNA sequencing in an orbiting spacecraft. 

A space-based DNA sequencer can identify 

microbes, diagnose diseases, understand 

crew member health, and potentially help 

detect DNA-based life elsewhere in the 

solar system.

The Cygnus NG (Northrop Grumman) cargo spacecraft is pictured in 

the grips of the Canadarm2 robotic arm. Cygnus would be released 

moments later as the ISS orbited over the Pacific Ocean. Visible in 

Cygnus’ Common Berthing Mechanism is the Slingshot small satellite 

deployer designed to deploy CubeSats from the cargo ship once it 

reaches a safe distance from the station.
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satellites from the space station that will re-enter the atmosphere. These 

opportunities can be used to demonstrate capabilities and techniques and 

increase knowledge of atmospheric re-entry.

Autonomous Systems

The definition of Autonomous 

Systems varies widely depending on 

the discipline. In the context of this 

booklet, it is defined as stated in the 

2020 NASA Technology Taxonomy: 

An autonomous system (in the 

context of robotics, spacecraft, or 

aircraft) is a cross-domain capability 

that enables the system to operate in 

a dynamic environment independent 

of external control. 

In general, ISS serves as a test ground for technology demonstrations that aim 

to reduce the crew’s dependence on ground-based mission control and support. 

Under microgravity conditions, NASA’s sponsors and partners can test autonomous 

concepts such as systems anomaly detection, precursor detection, issue detection 

and isolation, augmented reality (AR), autonomous medical skill and & decision 

support systems, in-flight autonomous logistics, fault diagnosis and prognosis, 

among many others.

Materials, Structures, Mechanical Systems, and Manufacturing

Long-duration exploration missions 

experience the ultraviolet, thermal and 

energized particle radiation environment 

of space requiring the use of materials 

on spacecraft that can survive these 

harsh conditions. ISS offers longduration space exposure for materials 

evaluation. Space station return 

vehicles can also be used to expose 

sample materials being considered for 

the return environment.

Seeker, an automated extravehicular free-flying inspector 

CubeSat, and its communication link, Kenobi. The primary 

objective of the Seeker mission is to demonstrate a 

path toward an inspection capability for future crewed 

space missions. 

View of Materials on ISS Experiment - 8 (MISSE-8) installed 

on the starboard truss. Photo taken by Expedition 28 Flight 

Engineer (FE) Ron Garan during a session of Extravehicular 

Activity (EVA).
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Thermal Management Systems

Besides re-entry thermal protection, 

spacecraft thermal technologies are 

needed to maintain cryogenic systems and 

thermal control of a spacecraft’s systems 

and internal environment.

Cryogenic systems contain fluids in 

two-phased regimes. Thermal insulation 

and recapture, fluid flow, and level 

measurement of these fluids are uniquely 

affected by the space and microgravity 

environment. Demonstrating system 

capabilities in the relevant environment 

of ISS would demonstrate needed 

exploration capabilities.

Heat rejection technology should operate efficiently and reliably across a wide 

range of thermal environments. Future spacecraft will benefit from advanced 

technologies and systems that can efficiently maintain heat loads in both the hot 

and cold environments of space.

Guidance, Navigation, and Control (GN&C)

Guidance, Navigation, and Control (GN&C) is a vast area important to 

all forms of aerospace systems. Onboard ISS, some facilities are provided 

specifically to test and demonstrate GN&C capabilities systems such as free 

flyers and CubeSats. Ultimately, the ISS serves as a microgravity laboratory for 

technology demonstration of systems that need GN&C testing to complete 

their design objectives.

The STP-H5-Electro-Hydro Dynamics (STP-H5 EHD) 

investigation demonstrated the long-term operation of a 

thermal control system on ISS.
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ISS provides investigators with a variety of accommodations and resources. 

Accommodations include internal or pressurized habitable volume, external 

exposure to the space environment, transportation to and from the space station, 

and deployable options.

A few of the accommodations more commonly utilized by technology 

demonstration payloads are highlighted here. For a more comprehensive 

description of the facilities and accommodations on ISS, the reader is referred 

to the International Space Station Facilities Book.

Internal

Internal to ISS, the technology and system demonstrations will be exposed to the 

nominal habitable station environment.

Expedite the Processing of Experiments for Space Station (EXPRESS) Racks

Internal to the space station habitable volume, technology demonstrations 

can be installed in the EXPRESS racks. EXPRESS racks support multi-discipline 

investigations and provide several resources that can be utilized in the 

technology demonstration.

ISS Accommodations

 System ISS Locker Locations ISIS Drawer Locations Rack-Level Accommodations

Structural Volume: 2 cubic feet 

Internal Dimensions:

20.32 x 17.34 x 9.97 inches

Volume: 1.26 cubic feet 

Internal Dimensions:

23.25 x 16.62 x 6.0 inches

8 ISS Lockers

2 ISIS Drawers (4 Panel Unit)

Power 28 Vdc, 0 - 500 W 28 Vdc, 0 - 500 W 2000 Watts 28 Vdc power

Air Cooling < 200 Watts < 100 Watts 1200 Watts

Thermal Control System 

Water Cooling

500 Watts (2 positions per rack) 500 Watts (2 positions per rack) 2 positions per rack

Command & Data Handling RS422 Analog Ethernet 5 Vdc 

Discrete

Ethernet 802.3*

WiFi Ethernet 802.11b/g* 

RS422 Analog Ethernet 5 Vdc 

Discrete

Ethernet 802.3*

WiFi Ethernet 802.11b/g*

RS422 Analog Ethernet 5 Vdc 

Discrete

Ethernet 802.3*

WiFi Ethernet 802.11b/g*

Video NTSC/RS170A

SDI or HDI via JSL-based 

encoder*

NTSC/RS170A

SDI or HDI via JSL-based 

encoder*

NTSC/RS170A

SDI or HDI via JSL-based 

encoder*

Vacuum Exhaust System 1 payload interface per rack 1 payload interface per rack 1 payload interface per rack

Nitrogen 1 payload interface per rack 1 payload interface per rack 1 payload interface per rack

Table Notes: * These interfaces may require unique hardware and software to enable their use.

EXPRESS Rack Resources
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EXPRESS Rack Subrack-size payload capability with 

standard utilities such as power, data, 

cooling and gases 

EXPRESS 8/2 Configuration 

8/2 Payload Configuration 

(8 ISS Lockers, 

2 Powered ISIS Drawers) 

International

Standard 

Payload Rack 

 Secondary 

Structure & 

Subsystems 

ISS Locker International Sub rack Interface

Standard Drawer 

Features 

4 rear captive fastener Features attachments 4 PU (Panel Unit) Friction hinge Blind Connectors Dual door locks Locking Handles Installation tool Weight – 27 lbs guides on 4 corners 

Weight – 12 lbs Rated to at least 37 lbs 
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Station-to-Internal-Facility Rack Resources 

The resources listed below are available in various rack locations on ISS. 

Aisle-Deployed Payloads

In some cases, small technology 

demonstrations can be installed 

or demonstrated outside of 

racks in a manner that does not 

interfere with crew passage or 

operations. In these instances, 

power and data resources can 

be provided to a payload from 

an EXPRESS Rack.

POWER 3, 6 or 12kw, 114.5-126 voltage, direct current (VDC)

DATA Low Rate MIL-STD-1553 bus 10 Kpbs

High Rate 100 Mbps

Ethernet 10/100*/1000* Mbps

Video NTSC, SDI or HDI via JSL-based encoder*

GASES Nitrogen Flow = 0.1 kg/min minimum;

517-827 kPa nominal; 

1379 kPa, maximum

Argon, carbon dioxide, helium 517-768 kPa nominal; 

1379 kPa, maximum

COOLING LOOPS Moderate Temperature 16.1oC – 18.3oC

Flow Rate 0 – 45.36 kg/h

Low Temperature 3.3oC – 5.6oC

Flow Rate 233 kg/h

VACUUM Venting 10-3 torr in less than 2h for single payload 

of 100 L

Vacuum Resource 10-3 torr (to maintain vacuum only, not for 

venting)

Table Notes: * These interfaces may require unique hardware and software to enable their use.

This cube containing Space Tango - 

Cubelab Satellite Demonstrator was part 

of TangoLab Mission-25.
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Nanoracks Nanode and Nanolabs

The Nanoracks Nanode is a 

commercial facility that interfaces 

between individual Nanolab Modules 

and the ISS, providing mechanical 

mounting points and electrical 

connections for power, data, and 

communication capabilities. Each 

Nanode platform is installed in its own 

EXPRESS rack locker. The Nanoracks 

Nanode Assembly with Nanolabs 

(payloads) installed is shown in the 

figure to the left.

Nanolabs are payloads that can be 

developed in varying sizes to meet 

science needs. The Nanode payload 

interface is designed to accommodate 

up to 12 standard Nanolab Modules. 

Nanolab modules longer than 2U (20 

cm) and up to 4U (40 cm) in length 

can be accommodated by laying 

horizontally in a retention slot and 

covering multiple connector positions. 

Other possible non-standard payload 

sizes can be assessed/considered for 

Nanode if they do not exceed the 

overall size of the payload volume. 

Any non-standard size will require 

additional evaluation and approval 

by Nanoracks. 

NanoRacks Nanode (Mainframe) Payload Accommodations

The Quest Institute-NanoLab Unit 3 contains 15 Nanolab experiments from students in the United States and Singapore.
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ISS Cold Stowage

NASA’s vision for humans pursuing deep space flight involves the collection of 

science in low earth orbit aboard the International Space Station (ISS). As a service 

to the science community, Johnson Space Center (JSC) has developed hardware and 

processes to preserve collected science on the ISS and transfer it safely back to the 

Principle Technologists. Cold Stowage consists of hardware, both active and passive, 

that transports science to/from the International Space Station (ISS).

Example Nanolabs
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ISS Passive Cold Stowage Accommodations

Double Coldbags (DCBs) have highly insulated 

walls and are designed to carry payload science 

at controlled temperatures by using Phase 

Change Material (PCM) to maintain specific 

temperatures for a prolonged period of time. 

The DCB is rectangular and fits in a single ISS 

locker. It is commonly used to transport science 

to and from the ISS on visiting vehicles.

Mini Coldbags (MCBs) are similar to DCBs 

but are significantly smaller. This coldbag has 

been optimized for return on a Soyuz vehicle. 

The MCB can also be used within a Glovebox as 

a means to immediately begin cooling samples 

after collection.

Ice Bricks are designed to provide cooling or 

incubation to scientific specimens requiring 

specific temperature ranges during transport to/

from the ISS. They are designed to work with 

other insulated transporters (e.g. DCB, MCB) 

to maintain specific temperatures between 

-32°C and +37°C. Ice Bricks are reconditioned 

using active hardware (MELFI, Glacier, 

Polar, MERLIN).

The Cold Stowage team is part of the International Space Station (ISS) program. 

JSC manages the operation, support and integration tasks provided by Jacobs 

Technology and the University of Alabama Birmingham (UAB). Cold Stowage 

provides controlled environments to meet temperature requirements during 

ascent, on-orbit operations, and return, in relation to International Space Station 

Payload Science.
19

ISS Cold Stowage Active Hardware

The Minus Eighty degree Laboratory Freezer for the 

International Space Station (MELFI) is a refrigerator/

freezer used to preserve science samples on the ISS. 

MELFI has four insulated dewars which can be set 

independently to +2°C, -35°, or -95°C.

MERLIN is a single ISS locker-sized incubator/

fridge/freezer. The primary functions of MERLIN 

are to provide temperature-specific environments 

for samples aboard ISS and thermal control in 

visiting vehicles. MERLIN is designed to support 

experiments requiring temperatures between 

+4°C and +40°C for launch/return, and -20°C to 

+48°C on ISS.

The Glovebox Freezer and Cryo Chiller provide the 

capability to rapidly freeze science samples at rates 

approaching those of Liquid Nitrogen on the ground. 

Samples are frozen via a conduction interface at 

-185°C. A “sample cartridge” provides the conduction 

interface for science samples when inserted into either 

the Glovebox Freezer or Cryo Chiller.

The Cryo-Chiller is a single ISS locker-sized 

freezer that supports experiments at -160°C for 

launch and return in addition to on orbit rapid 

freeze operations.

The Glacier is a double ISS locker-sized cryogenic 

freezer. The primary function of Glacier is to provide 

cryogenic preservation of science samples aboard the 

ISS and thermal control in visiting vehicles. Glacier 

is designed to support experiments that require 

temperatures between -95°C and +4°C for launch/

return and –160°C to +4°C on ISS.
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Other Internal Tools

Nanoracks has optical and reflective 

microscopes available for commercial 

use with digital image retrieval for 

ISS experiments. A Nanoracks Plate 

Reader is also available to monitor 

samples in microtiter plates with 96 

wells with controls for temperature 

and stirring. 

The Nanoracks Microscopes facility 

includes three commercial off-the-shelf 

optical and reflective microscopes. 

They use plug-and-play USB 

technology and allow crew members 

to analyze and digitally transfer 

images of ISS in-orbit samples. 

Airlock Options

Japanese Experiment Module (JEM) Airlock

The JEM has an equipment airlock that 

allows the transfer of payloads between 

the internal pressurized cabin and space. 

Payloads attach to a slide table that 

extends into the cabin for crew access or 

extends out the JEM Exposed Facility 

for access by either the JEM robotic arm 

or the Mobile Servicing System (MSS). 

NanoRacks Microscope-3 is an off-the-shelf Universal Serial 

Bus (USB) microscope. Image courtesy of NanoRacks LLC.
21

The JEM arm or MSS moves the payload between the JEM airlock and external ISS 

locations. The JEM airlock can accommodate a payload up to 300 kg in mass that 

fits within the dimensions of the airlock. The general dimensions and form of the 

airlock volume are shown above and are 32 inches in width. JEM airlock usage is 

negotiated on an as-needed basis.

Bishop Airlock

The Nanoracks Bishop Airlock is a commercial airlock that offers an array of 

different capabilities. From microsatellite deployment to externally hosted payloads 

to microgravity experiments, the Bishop Airlock can accommodate a variety of large 

or small payloads with unique pointing possibilities. The Bishop Airlock is attached 

to the Node 3 Port berthing ring. 

Bishop Airlock Satellite Deployment Nominal Payload Envelope

• Maximum payload size 44.2” x 44.2” x 50” and 709 lbs

• Must fit through Node 3 Hatch

– 46” if CPAs are rotated and kick-plate installed (nominal)

– 50” if CPAs are removed (premier)

• Maximum 144U per Airlock sortie

• Various satellite sizes can be hosted during one sortie. Can combine CubeSat 

deployer with multiple MicroSats.

Deployment commands are operated by the Nanoracks Operations Team.
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The Bishop Airlock can accommodate multiple options for deploying various 

payload sizes. Examples are shown below.

Nanoracks “HayBale” Deployable 

Cubesat Dispenser (144U capability 

in configuration shown)

Representative MicroSat (~65kg). 

This is the max size that can go 

through JEM Airlock. Bishop can fit 

up to four of these satellites in 

at one time.

HayBale is deployed from Bishop 

in similar fashion to ESPA/Kaberclass satellites, using Nanoracks 

Separation System or Lightband. As 

“HayBale” is separated from ISS, the 

orbiting “HayBale” deploys pairs of 

cubesats over time until deployments are complete. Empty “HayBale” orbit degrades and “HayBale” 

is destroyed upon re-entry.

Two Small Satellites

Haybale CubeSat 

Deployer

Pressurized or unpressurized launch opportunities are available. Oceaneering 

GOLD 2 connector provides electrical, mechanical and robotic interface. Infinite 

pointing options are available while on the SSRMS (CanadaArm) – including Ram, 

Wake, Zenith, and Nadir. 
23

Accommodations for Hosted Payloads

The Bishop Airlock has six external payload sites to provide long duration research 

external to the ISS. 

Nominal Payload Envelope:

• 500 lbs (227 kg)

• Exceedances may be considered on a case-by-case basis

Power: 120 VDC; 350 watts (nominal)

• Maximum 700 watts but must coordinated with Nanoracks: total Airlock 

payload power available is 2.6 kW berthed and 1.8kW un-berthed, Payload 

usage of this shared resource is managed by Nanoracks.

Data: Ethernet protocol (nominal)

• 100 Mb/sec to Airlock avionics

• Data rate from Airlock to ISS: 100 Mb/sec berthed (hardwired to Node 3); 

10 Mb/sec un-berthed (WIFI)

• Data rate to ground to be negotiated with NASA

• Data storage capability within Airlock avionics

Redundant power and data interfaces

• Redundant fiber optics and coaxial connections also available and terminated 

inside of Airlock pressure shell

NADIR

External

Payload Sites

Conceptual payload 

volumes shown for 

visual purposes only
24

Accommodations for Microgravity Research 

In addition to the externally hosted and satellite deployments, the Bishop Airlock 

also has the capability to accommodate pressurized microgravity research within the 

Bishop Airlock while attached to Node 3 Port location.

Nominal Payload Envelope 

• Maximum payload size 44.2” x 44.2” x 50” and 709 lbs

• Must fit through Node 3 Hatch 

– 46” if CPAs rotated and kick-plate installed (nominal) 

– 50” if CPA’s removed (premier)

Power: 120 VDC; 350 watts (nominal)

• Maximum 700 watts but must coordinated with Nanoracks as total Airlock 

payload power available is 2.6 kW berthed and 1.8kW un-berthed – This is a 

shared resource so payload usage will be managed by Nanoracks.

Data: Ethernet protocol (nominal)

• 100 Mb/sec to Airlock avionics

• Data rate from Airlock to ISS: 100 Mb/sec berthed (hardwired to Node 3); 

10 Mb/sec un-berthed (WIFI)

• Data rate to ground to be negotiated with NASA

• Data storage capability within Airlock avionics

Operations conducted by in the Nanoracks “Bridge” in coordination with NASA, 

crew, and customer.

Representative ISS 

locker type payloads
25

External

ISS provides a variety of external sites and services to conduct payload 

investigations.

EXPRESS Logistics Carrier (ELC)

Technology demonstrations performed externally on ISS can be attached to one of 

the ELCs. The ELC locations offer viewing options ranging from nadir to zenith 

and points in between. Payload demonstrations attaching to the ELC will require 

the use of a Flight Releasable Attachment Mechanism (FRAM). The FRAM 

provides mechanical, electrical, thermal, data, EVA, and robotic interfaces to ISS.

The medium rate data interface will be updated at each ELC location to 100 Mbps 

two-way wireless LAN.

Mass capacity 227 kg (500 lb)

Volume 1 m3

Power 750 W, 113 – 126 Vdc;

500 W at 28Vdc per adapter

Thermal Active heating, passive cooling

Low-rate data 10 Kbps (MIL-STD-1553)

Medium-rate data 6 Mbps (shared)

Wi-Fi Ethernet* 100 Mbps (shared)

Sites available per ELC 2 Sites

Total ELC sites available 8 Sites

Table Notes: *These interfaces may require unique hardware and software to enable their use.

ELC External Research Accommodations
26

Pre-Decisional, Internal Use Only | HUMAN SPACE FLIGHT TECHNICAL INTEGRATION CONTRACT (HSFTIC) | 1 Classified as EAR99 – Refer to Title Page Classified as EAR99 – Refer to Title Page

OBSS OSE

ELC3

(ULF6)

P3 Upper

Outboard

[U1]

ELC1

(ULF3)

P3 Lower

Outboard

[U2]

ELC4

(ULF5)

S3 Lower

Inboard

[P4]

ESP3

(13A.1)

S3 Lower

Outboard

[P3]

AMS

(ULF6)

S3 Upper

Inboard

[P2]

ELC2

(ULF3)

S3 Upper

Outboard

[P1]

ESP2

(LF1)

Airlock

ESP1

(5A.1)

Lab

JEM EF

(2J/A)

Columbus EPF

(1E)

1 2 3

[P#] = PAS[U#] = UCCAS

# = MT Worksite

4 5 6 7 8

Bartolomeo

(SpX-20)

Nanoracks Airlock

(SpX-21)

Node 3

ISS Attach Sites
27

JEM Exposed Facility (JEM-EF)

On the port side of ISS, the JEM provides accommodations for attaching external 

payloads. The JEM-EF is a multipurpose experiment platform where various 

investigations/demonstrations can be performed. The JEM-EF has 12 attachment 

ports for external payload and can accommodate up to ten payloads simultaneously. 

Columbus Exposed Facility (EF)

Located on the starboard side of space station, the ESA (European Space Agency) 

Columbus module also provides an external facility to accommodate external 

technology demonstrators. Similar to the FRAMs, the technology demonstration 

payload will be provided a Columbus External Payload Adapter (CEPA) to interface 

to the space station services.

 Location Viewing Payload Size Power Data

SOZ Zenith 226kg +CEPA 1.25 kW at 120VDC

2.5 kW max

1553 -1 Mbs

SOX Ram ethernet - up to 10 Mbs

SDX Ram

SDN Nadir

Columbus EF Resources
28

NanoRacks External Platform (NREP) 

NanoRacks External Platform is the first commercial research capability for testing 

science investigations, sensors, and electronic technologies in space. The NREP 

is located on the JEM-EF, and payloads are deployed by the Japanese Experiment 

Module Remote Manipulator System (JEMRMS). 

The attachment port on the JEM-EF provides mechanical, thermal and electrical 

interfaces to the attached payloads. This interface mechanism is called Experimental 

Exchange Unit (EEU).

Mass Capacity 550 kg (1150 lb) at standard site

2250 kg (5550 lb) at large site

Volume 1.5 m3

Power 3 – 6 kW, 113 – 126 Vdc;

Thermal 3 – 6 kW cooling

Low-rate data 10 Mbps (MIL-STD-1553)

High-rate data 43 Mbps (shared)

Wi-Fi Ethernet* 100 Mbps (shared)

Sites available to NASA 5 Sites

Table Notes: *These interfaces may require unique hardware and software to enable their use.

JEM External Resources

The Japanese Experiment Module Remote Manipulator System (JEMRMS) moves to install the NanoRacks External 

Platform (NREP) on the JEM (Japanese Experiment Module) Exposed Facility (JEF).
29

External Platform Hosting Features

Location: JEM External Facility (ISS)

Form Factor (Active): Five 4U locations

Form Factor (Passive): Four 3U locations

Payload Volume: 32U total

Pointing: Nadir

Mission Lifetime: 15 weeks (nominal), extension optional

Maximum Capacity: 35 kg (1 kg/U mass allocation)

Power: 28 VDC (30W nominal, 50W max per payload)

USB Power: 5 VDC, 500mA

Nominal Turnover: L-3 Months

Non-standard services and accommodations:

• Extended mission duration

• Additional power

• Additional data services

• Non-standard form factors

Robotic Capabilities

EVAs (spacewalks) at ISS are reserved to address critical maintenance activities. 

With limited spacewalk opportunities, external technology demonstration 

payloads must be robotically manipulated and installed. Currently, there are two 

robotic manipulator systems aboard ISS. These robotic systems were responsible for 

much of the construction of the space station and are now available for 

payload utilization.

Mobile Servicing System (MSS)

The MSS is part of the Canadian Space Agency’s contribution to ISS. It consists 

of the Space Station Remote Manipulator System, the Special Purpose Dexterous 

Manipulator, and the Mobile Base System. These, along with two robotics 

workstations, to operate the robotic systems from inside the space station, and the 

Mobile Transporter, which is used to transfer hardware along the length of the truss, 

are now assisting with payload utilization.
30

JEM Robotic Manipulator System (RMS)

The JAXA-provided RMS resides on the JEM-EF. This manipulator can be used 

to remove payloads from the JEM airlock for placement on the EF and can also be 

used with ISS small satellite deploying systems to launch deployable payloads.

Access to the External Environment

Payloads can gain access to the external environment in one of two ways. For 

large payloads that are destined for one of the payload accommodation sites, they 

can be launched to ISS inside the SpaceX Dragon Trunk. Once the Dragon has 

been captured and berthed to the space station, the MSS can be used to remove 

the payload and install it at its destination. Smaller payloads can be launched to 

ISS in the pressurized environment in one of the many launch vehicles and then 

transferred to the space environment through JAXA’s JEM airlock.

Robotic Interfaces

FRAMs and CEPAs are provided to technology payload developers as 

Government Furnished Equipment. Robotic interfaces are pre-integrated 

with the FRAMs and CEPAs.

In this image, the Canadian-built Dextre, also known as the Special Purpose Dextrous Manipulator (SPDM), is at top left. 

The station’s Canadarm2 is also featured.
31

Special Considerations

Special consideration should be given to externally-attached demonstration 

payloads in the following areas:

Contact Loads - Payloads that are maneuvered with a robotic manipulator are 

generally moved into and out of areas of tight clearance with station hardware. 

While every effort is made to prevent collision, there are some unpredictable failure 

cases where contact may occur. Ideally, payloads should be designed to withstand 

the energy imparted from this inadvertent contact.

Thermal Environment - In an effort to preserve as much in-orbit crew time 

as possible, a majority of in-orbit robotic operations are performed by ground 

controllers from the Mission Control Center (MCC). Applied constraints on 

the ground-controlled robotic motion can result in a long-duration transit to the 

payload’s destination. Given the thermal extremes that can be experienced during 

this timeframe, a payload developer should consider this when designing a payload’s 

thermal control system.

Deployable Small Satellites

ISS has limited capability to deploy small satellites from the space station for free 

flight and ultimate re-entry to Earth’s atmosphere. 

Platform Size, Approximate

mm (Inches)

Mass (Max, of Deployed 

satellite)

Location of Deployment

J-SODD 1U - 100 x 100 x 113.5 mm

(3.9 x 3.9 x 4.7 inches)

2U - 100 x 100 x 227.0 mm

(3.9 x 3.9 x 8.9 inches)

3U - 100 x 100 x 340.5 mm

(3.9 x 3.9 x 13.4 inches)

1.33 Kg/1U Deployed from ISS (JEM EF)

CYCLOPS 1117.6 x 762 x 279.4-533.4 mm 

(44L x 30W x 11-21H inches)

100 kg Deployed from ISS (JEM EF)

Space X 1U - 100 x 100 x 100 mm

(3.9 x 3.9 x 3.9 inches)

2U - 100 x 100 x 200 mm

(3.9 x 3.9 x 6.8 inches)

3U - 100 x 100 x 300 mm

(3.9 x 3.9 x 10.7 inches)

1.33 kg/1U Deployed from Space X prior to 

ISS docking
32

 Platform Size, Approximate Mass (Max, of Deployed Location of Deployment

 mm (Inches) satellite)

SEOPS Slingshot 1U – 119 x 119 x 100 mm

2U – 119 x 119 x 227 mm

3U – 119 x 199 x 366 mm

6U – 119 x 245 x 366 mm

12U – 245 x 245 x 366 mm

Optional tuna can is 88 mm 

max diameter, 46 mm long

1U – 2.0 kg 

2U – 4.0 Kg

3U – 6.0 kg

6U – 12.0 kg

12U – 24.0 kg

Deployed from Cyngus, post 

unberth from ISS

Note: Slingshot is compatible with 

both rail / tab formats.

Nanoracks CubeSat 

Deployer (NRCSD)

1U - 100 x 100 x 113.5 mm

(3.9 x 3.9 x 4.7 inches)

2U - 100 x 100 x 227.0 mm

(3.9 x 3.9 x 8.9 inches)

3U - 100 x 100 x 340.5 mm

(3.9 x 3.9 x 13.4 inches)

4U – 100 x 100 x 454.0 mm 

(3.9 x 3.9 x 17.8 inches)

5U - 100 x 100 x 567.5 mm 

(3.9 x 3.9 x 22.3 inches)

6U-100 x 100 x 681-740 mm 

(3.9 x 26.8 - 29.1 inches)

1U – 2.40 kg

2U – 3.60 kg

3U – 4.80 kg 

4U – 6.00 kg

5U – 7.20 kg

6U – 8.40 kg

Deployed from ISS (JEM EF)

Nanoracks DoubleWide 

Deployer (NRDD), Tabs

6U–116.2 x 239.2 x 366 mm 

(4.5 x 9.4 x 14.4 inches)

12U–116.2 x 239.2 x 732 mm 

(4.5 x 9.4 x 28.8 inches)

6U – 12.0 kg

12U – 18.0 kg

Deployed from ISS (JEM EF)

Nanoracks DoubleWide 

Deployer (NRDD), Rails

6U – 100 x 226.3 x 366 mm 

(3.9 x 8.9 x 14.4 inches)

12U - 100 x 226.3 x 732 mm 

(3.9 x 8.9 x 28.8 inches)

6U – 12.0 kg

12U – 18.0 kg

Deployed from ISS (JEM EF)

Nanoracks CubeSat 

Deployer – External 

(NRCSD-E)

1U - 100 x 100 x 113.5 mm

(3.9 x 3.9 x 4.7 inches)

2U - 100 x 100 x 227.0 mm

(3.9 x 3.9 x 8.9 inches)

3U - 100 x 100 x 340.5 mm

(3.9 x 3.9 x 13.4 inches)

4U - 100 x 100 x 454.0 mm 

(3.9 x 3.9 x 17.8 inches)

5U - 100 x 100 x 567.5 mm 

(3.9 x 3.9 x 22.3 inches)

6U (1Ux6U) - 100 x 100 x 

681.0 - 740.0 mm

(3.9 x 3.9 x 26.8 - 29.1 inches)

6U (2Ux3U) - 100 x 226.3 x 

366 mm (3.9 x 8.9 x 14.4 

inches)

12U (2Ux2Ux3U) - 226.3 x 

226.3 x 366 mm (8.9 x 8.9 x 

28.8 inches)

1U – 2.40 kg

2U – 3.60 kg

3U – 4.80 kg 

4U – 6.00 kg

5U – 7.20 kg

6U (1Ux6U)– 8.40 kg

6U (2Ux3U)– 12.0 kg

12U (2Ux2Ux3U) – 18.0 kg

Deployed from Cygnus post 

ISS un-berthing
33

 Platform Size, Approximate Mass (Max, of Deployed Location of Deployment

 mm (Inches) satellite)

Nanoracks Kaber 

Microsatellite Deployer

640 x 830 x 1079 mm 

(25.2 x 32.6 x 42.4 inches) 

87.8 Kg Deployed from ISS (JEM EF)

Nanoracks Bishop Airlock 1122 x 1122 x 1270 mm 

(44.2 x 44.2 x 50 inches) 

321.6 kg Deployed from ISS (NRAL)

Software and Avionics, ISS Command and Data Handling

Health and Status Data 

Health and status data include all of the parameters needed by the Crew on-orbit 

and Payload Operations on the ground to ensure that the payload is operating safely 

and correctly responding to commands. Some payloads, like those that control 

hazards, use the caution and warning system or are highly sophisticated, will be 

required to have health and status implemented with the payload.

Broadcast Ancillary Data (BAD) 

MIL-STD-1553 System distributes ISS BAD to all payloads Remote Terminals 

(RTs). BAD data contains most of ISS vehicle information that experiments may 

need like station location, position and pointing vector information. In addition, 

the ISS BAD data contains information about the current pressure, temperature 

and other environmental information data about the space station modules where 

payloads are located. If there is data a payload needs that is available and not 

currently in BAD, it is possible to have it added to BAD if the request is made early.

Unique Ancillary Data

Data available from within the Payload Multiplexer De-Multiplexer (PL MDM) 

that is not present in BAD can be transmitted to the payload via the definition 

of a unique ancillary data service. When initialized in the PL MDM, this data is 

transmitted to the payload via the 1553 bus or the Ethernet.
34

ISS Data Interfaces

The ISS downlink operates at a data rate up to 517 Mbps. The payload users share 

this bandwidth with ISS system operations (USOS, RS, and visiting vehicles). 

There are eight real-time downlink video channels and four two-way real-time audio 

channels. Typically, four video and two audio channels are dedicated to vehicle 

operations. Live video, two-way audio, and data bandwidth usage is scheduled via 

coordination with the POIC.

Data Interface Format Data Rate (1) Comments

Low Rate Data Link

(LRDL)

MIL-STD-1553 10kbps Nominally used for payload commanding 

and to gather health and status. Limited 

telemetry downlink is also available. 

Medium Rate Data Link

(MRDL)

Ethernet 802.3 10/100Mbps Ethernet input and output (downlink) available at most internal locations. Downlink via 

UDP available at most external sites. Not 

available at external truss sites. 

Joint Station LAN (JSL) Ethernet 802.3 10/100/1000Mbps Ethernet input and output (downlink) 

available at most internal locations.

High Rate Data Link

(HRDL)

TAXI Fiber-optic 100Mbps HRDL input and output is available at 

most internal sites. HRDL available at most 

external sites.

Video (2) NTSC 12.5Mbps Only available at internal International 

Standard Payload Rack ISPR sites. 

Video SDI or HDI via JSL-based 

encoder

Configurable (typically 

8-12 Mbps)

Available via MRDL or JSL interfaces.

Wireless Data Link WiFi Ethernet 802.11b/g 100Mbps Available to internal and external sites that 

are within range of the access point.

ISS Payload Data Links

Table Notes: (1) All station data links are shared resources. The data rate listed is the maximum data rate the link can 

support. (2) Because of the high demand for video downlink and high bandwidth use, it is recommended that the 

experiments encode and downlink video via MRDL when possible.
35

Payload Interfaces to the Communication Links

Data Downlink Availability: Downlink and Storage 

Space Network’s Tracking and Data Relay Satellite (TDRS) S-Band and Ku-Band 

coverage varies based on ISS attitude, location, and beta angle. Typically, coverage 

ranges from 90-95% on S-band and 80-90% on Ku-band. Payloads should plan to 

internally store and retain any data essential for the success of the experiment until 

the principle investigator has verified receipt of the data. Downlinked data is stored 

by payload operations and can be transmitted to the payload user if they are unable 

to receive the data when it is downlinked. During loss of signal (LOS) periods 

between the ISS and TDRS, the Ku-band Integrated Communications Unit (ICU) 

(1.6 Tbits total storage capability) records payload data that has been designated 

by POIC for LOS auto-record. The ICU is capable of storing all downlink data 

for up to a 90-minute LOS period. Upon Acquisition of Signal (AOS), the ICU 

automatically downlinks ICU-stored data. 

Payloads

Space

Network

Tracking

and Data

Relay

Satellite

(TDRS)

Note:

Available

interfaces are

dependent on

the payload

locations.

Not all 

interfaces are at all

locations.

Mil-Std-1553

Vehicle

Systems

Crew

Member

Ethernet Data Non-Critical Commanding & Telemetry

Data Non-Critical Commanding & Telemetry

Includes up to

6 channels of

real-time

digital video

Includes up to

8 channels of

real-time video

Two Audio Channels

(dedicated to vehicle operations)

Two Audio Channels

(payload operations &

private communications)

Control & Telemetry

Conversion Function

(in Express Rack or

Express Carrier)

192 Kbps Return

72 Kbps Forward

517 Mbps Return

21 Mbps Forward

Ethernet

Wi-Fi

TAXI FIber

Data

Up to 6 channels

Analog & Discrete Signals

NTSC

TAXI Fiber

Vehicle

Systems

Crew

Member

Audio System

Low Rate Data Link

(LRDL)

High Rate Data Link

(HRDL)

Video System

Medium Rate Data

Link (MRDL)

Joint Station

Local Area

Network

(JSL)

S-band

Communication

Link

Ku-band

Communication

Link

Audio System

Payload Operations

Integration Center

(NASA-MSFC)

Mission Control

Center

(NASA-JSC)

HRDL Gateway
36

Command/Data Latency

During periods of TDRS coverage, the following command uplink and data 

downlink latencies can be achieved if automatic enabling of payload commanding 

during Ku-band coverage has been worked out ahead of time with NASA Marshall 

Space Flight Center Payload Operations Integration Facility:

• Data Downlink Latency, station payload-to-payload developer remote site: 5 sec

• Command Uplink Latency, payload developer remote site to station payload: 

10 sec with payload command confirmation, up to 15 sec total.

Commands and data sent to ISS via S-Band is encrypted at MCC – Houston prior 

to transmission for security reasons. The ISS does not perform any data encryption 

on either the Ku-band or S-band downlinks. The payload is responsible for 

protecting crew health or medically sensitive data or any proprietary data prior to 

sending it to the ISS data and communication systems for downlink.

TDRSS

Commands, Uplinks,

Voice

Vehicle Telemetry,

Voice, Video

Payload/Ku-band &

Vehicle Telemetry

Commands, Uplinks

US Payload Commands, Uplinks

Internet Payload/Ku-band & Ancillary Telemetry

Planning Products, Voice, Ops Mgmt

MCCH to

International

Partner

Services

Planning Products, Voice, Ops Mgmt, Other

Mission

Control Center

Houston

International

Partner

Facilities

NASA

Telescience

Support

Centers

Payload

User Sites

TReK

Payload Ops

Control Center

Huntsville

Russia

Europe

Japan

Italy

Canada

GRC

ARC

JSC

MSFC

White Sands Complex, New Mexico

ISS

Data Security and Encryption
37

Payload Software and Displays 

A unique payload software Interface Control Document (ICD) is developed for 

each payload to document the software and data interfaces. Payloads are required 

to contain and control all of their hazards internally and are not permitted to use 

any station C&DH interface or data as a required control of a hazard. Software and 

firmware used in support of an experiment on ISS must be configuration managed 

and quality controlled. Software that will need to be uplinked to ISS during the 

mission must successfully complete NASA’s software update and verification 

process and be virus scanned prior to uplink. At times, software updates must also 

successfully repeat a vulnerability and penetration set of IT security scans prior to 

uplink. ISS provides the use of a single fleet of laptops on-orbit. These ISS laptops 

will be refreshed every few years to stay current with advances in technology. 

Displays that are to be used by the crew on-orbit in support of an experiment 

must be delivered to NASA and will be checked for adherence to crew standards 

and training well in advance of being used on-orbit. The payload software and 

display implementation plan will be established with the ISSP Program based on 

the payload type, operational and flight data dependencies, as well as the assigned 

operational Increment. 

Telescience Resource Kit – Payload Operations Interface

The Telescience Resource Kit (TREK) is a suite of PC-based software applications 

provided to payload developers by the ISS Program that is used by scientists and 

engineers to monitor and control payloads aboard the space station.

The PC running the TReK software can be located anywhere in the world. 

This provides a way to monitor and control experiments located on the ISS in 

the USOS module from their offices and laboratories at home.

TREK can be used to receive payload data from ISS, distributed by the Payload 

Operations and Integration Center and to perform local data functions such 

as processing the data, storing it in local files and forwarding it to other 

computer systems.

Users can extend TREK capabilities by using the TREK Application Programming 

Interface, together with commercial software products, to utilize local telemetry and 

command functions.
38

Internal Atmosphere

The nominal station atmosphere is shown in the table below:

Orbit Characteristics

Over the course of 72 hours and terrestrial weather conditions permitting, all 

geographic locations between 51.6 north and south latitude can be observed. ISS 

provides coverage of 85 percent of the Earth’s surface and 95 percent of the world’s 

populated landmass every 1 to 3 days.

The station altitude generally varies with the solar cycle, with the altitude 

maintained higher during solar maximum. Eccentricity of the station’s orbit is 

maintained at <0.003. In support of visiting vehicles, the altitude is adjusted to 

accommodate the visiting vehicles’ performance parameters. In general, the space 

station altitude will remain within 395-417 km (245-259 miles).

ISS Characteristics

 Atmospheric Conditions on ISS Nominal Value

Pressure 14.7 PSI

Dew point 4.4 to 15.6°C (40 to 60°F)

Carbon dioxide partial pressure 5.3 mm Hg

Peak exposure 7.6 mm Hg 

Oxygen partial pressure 3.1 PSI ppO2

Cabin air temperature 17 to 28°C (63 to 82°F)
39

Guidance, Navigation, and Control Characteristics

ISS Attitude Torque Equilibrium Attitude (TEA) & Wobble Oscillation 

Description – for stage configurations in the foreseeable future (i.e., no orbiter or 

orbiter-sized vehicles docked on the space station), the predicted TEA ranges are: 

Roll: -1.0~+3.0 deg.

Pitch: -7.0~+2.0 deg. 

Yaw: -15~+15 deg.

ISS coverage in 24 hrs for a 70°-swath optical payload. (Courtesy of ESA)

Peak to Peak Attitude

Oscillations Per Orbit

Peak Attitude Variation from Steady 

State Orbit Average Attitude Performance Descriptions Roll (X)

(deg)

Pitch (Y)

(deg)

Yaw (Z)

(deg)

Roll (X)

(deg)

Pitch (Y)

(deg)

Yaw (Z)

(deg)

Non-Micro-Gravity (Assembly Stages) Non-Propulsive (Momentum 

Manager) Attitude Control Performance Requirement 10.0 10.0 10.0 +/- 5 +/- 5 +/- 5 

Micro-Gravity (Assembly Complete) Non-Propulsive (Momentum 

Manager) Attitude Control Performance Requirement 7.0 7.0 7.0 +/- 3.5 +/- 3.5 +/- 3.5 

Typical Steady-State Performance of Minimum CMG momentum 

oscillation Momentum Manager Controller 1.6 1.6 2.0 +/- 0.8 +/- 0.8 +/- 1 

Typical Steady-State Performance of Minimum Attitude oscillation 

Momentum Manager Controller 1.6 0.4 0.2 +/- 0.8 +/- 0.2 +/- 0.1

Typical Steady-State Performance of Minimum CMG momentum 

& Attitude oscillation Blended Momentum Manager Controller 1.6 0.7 1.2 +/- 0.8 +/- 0.35 +/- 0.6
40

Microgravity Environment

The following illustration indicates typical observed microgravity characteristics. 

External Contamination

ISS provides an exceptionally clean environment to external payloads and science assets. 

External contamination control requirements limit contaminant deposition to 130Å/

year on external payloads and station sensitive surfaces.

Specified levels are lower than any previous space station (Mir, Skylab, Salyut) by 

several orders of magnitude. Measurements of contaminant deposition on ISS-returned 

hardware have demonstrated that requirements are met at station payload sites.

SDMS S3 Max 1/3 Octave Band - GMT 076, 085, and 086 2 10

101

Microg RMS

0 10

-1 10 -2 -1 0 1 10 10 10 10

Freq

 Experiment Side Requirement (130Å/year) Measured

MISSE 2 ram 520 Å (4 years) 50 Å

wake 520 Å (4 years) 500 Å

Node 1 nadir 

window cover

nadir 390 Å (3 years) 50 Å

Analysis concluded peak ELC rotations on the order of 0.03 degrees per axis (in the quiescent mode).
41

Transportation to ISS

ISS Cargo Vehicles

Several transport vehicles are available to launch payloads to ISS. When a technology 

demonstrator becomes a station payload, the ISS Program manifests the payload on 

the appropriate vehicle. Payload developers do not manifest directly with the launch 

provider for transport to ISS. Allowable upmass and volume capacities for ISS 

destination locations are provided below.

The SpaceX CRS2 Dragon vehicle has the capability to 

launch and dispose of up to 1712kg of Flight Releasable 

Attachment Mechanism (FRAM), JEM-EF or direct 

mount unpressurized cargo. The dragon trunk can 

accommodate up to three FRAM, two JEM-EF, one 

direct mount or a combination of unpressurized cargo 

types, depending on the mission-specific manifest. 

The unpressurized cargo environments can be found 

in the Cargo Dragon 2 Unpressurized Interface 

Requirement Documents (IRD).

The Sierra Space Dream Chaser Cargo (DCC)

vehicle has the capability to launch and dispose of a 

total unpressurized cargo complement up to 1500kg 

of FRAM, JEM-EF or direct mount unpressurized 

cargo. The DCC Cargo Module (CM) accommodates 

up to three unpressurized cargo items ranging in size 

and mass, depending on the mission-specific manifest. 

The unpressurized cargo environments can be found 

in the CM to Unpressurized IRD.

The JAXA HTV-X vehicle has the capability to launch 

and dispose of a total unpressurized cargo complement 

up to 1750kg of FRAM, JEM-EF or direct mount 

unpressurized cargo. The HTV-X Unpressurized 

Cargo Support System (UPCSS) accommodates up 

to four unpressurized cargo items ranging in size and 

mass, depending on the mission-specific manifest. 

The unpressurized cargo environments can be found 

in the HTV-X Unpressurized Cargo Standard IRD.

SpaceX Dragon Commercial Resupply Vehicle

Sierra Space Dream Chaser Cargo System

JAXA HTV-X Cargo System
42

The Northrup Grumman (NG) Cygnus Spacecraft 

Pressurized Cargo Module (PCM) has the capability 

to dispose of up to 1200kg of FRAM unpressurized 

cargo. The Cygnus PCM accommodates up to two 

Passive Flight Releasable Attachment Mechanism 

(PFRAM) worksites located on the exterior of the 

PCM. The unpressurized cargo environments can be 

found in the Cygnus Vehicle Unpressurized Cargo 

Interface Control Document (Disposal).

Note: Currently, only the SpaceX vehicle is capable of transporting external FRAM or 

CEPA payloads to ISS.

Cygnus NG (Northrup Grumman)

Attach Payload 

Location

Allowable Payload 

Weight (including 

Flight Support 

Equipment)

Accommodation 

Weight (including 

adapter plate)

Total Weight Payload Volume

(W x H x L)

490 lb. 250 lb. 740 lb. 34” x 49” x 46”

ELC (ExPA)

(222 kg) (114 kg) (336 kg) (863mm x 1244mm x 1168mm)

490 lb. 250 lb. 740 lb. 34” x 49” x 46”

Columbus 

(CEPA) (222 kg) (114 kg) (336 kg) (863mm x 1244mm x 1168mm)

979 lb. 121 lb. 1100 lb. 31.5” x 39.4” x 72.8”

JEM-EF

(445 kg) (55 kg) (500 kg) (800mm x 1000mm x 1850mm)

Allowable Up-Mass and Volume Capacity
43

Every experiment on the space station needs to be sponsored and funded to be 

developed, integrated, flown, and operated onboard. Several sources of funding 

are available to scientists for research, payload development, payload processing 

at NASA facilities, on-orbit operation, and more. 

In general, NASA funding for space station use is obtained through NASA 

Research Announcements (NRAs). Funding from other government agencies, 

private, and non-profit entities to use the space station is obtained through 

research opportunities released by ISS U.S. National Laboratory, otherwise known 

as the Center for the Advancement of Science in Space (CASIS). Space Station 

International Partner funding can be obtained through their respective agencies. 

ISS U.S. National Laboratory 

In 2011, NASA finalized a cooperative agreement with CASIS to manage the 

International Space Station U.S. National Laboratory (ISS National Lab). 

The independent, nonprofit research management organization ensures the 

station’s unique capabilities are available to the broadest possible cross section 

of U.S. scientific, technological and industrial communities.

The ISS National Lab develops and manages a varied research and development 

portfolio based on U.S. national needs for basic and applied research. It establishes 

a marketplace to facilitate matching research pathways with qualified funding 

sources and stimulates interest in using the national lab for research and 

technology demonstrations and as a platform for science, technology, engineering 

and mathematics education. The goal is to support, promote and accelerate 

innovations and new discoveries in science, engineering and technology that 

will improve life on Earth.

More information on ISS National Lab, including proposal announcements, 

is available at www.issnationallab.org.

Funding, Developing, and 

Launching Research to ISS
44

Other Government Agencies 

Potential funding for research on the ISS is also available via governmental 

partnerships with ISS U.S. National Laboratory and includes (but is not limited to) 

such government agencies as:

• Department of Energy (DOE)

• Department of Defense (DOD)

• National Science Foundation (NSF)

• National Institutes of Health (NIH)

• U.S. Department of Agriculture (USDA) International Funding Sources

International Funding Sources

Unique and integral to the ISS are the partnerships established between the 

United States, Russia, Japan, Canada and Europe. All partners share in the greatest 

international project of all time, providing various research and experiment 

opportunities for all. These organizations – Japan Aerospace Exploration Agency 

(JAXA), Canadian Space Agency (CSA), ESA (European Space Agency), Russian 

space agency Roscosmos, Centre National d’Etudes Spatiales (CNES), and the 

German Aerospace Center (DLR) – provide potential funding opportunities for 

international scientists from many diverse disciplines.
45

ISS Commercial

An additional method to conduct research and other activity on the ISS is through 

commercial activity. NASA has opened the International Space Station (ISS) for 

business to enable commercial and marketing opportunities on the microgravity 

laboratory. Since then, there has been a growing demand for commercial and 

marketing activities from both traditional aerospace companies and from novel 

industries, demonstrating the benefits of the space station to help catalyze and 

expand space exploration markets and the low-Earth orbit economy.

NASA’s Commercial LEO Development Program supports the development of 

commercially-owned and operated LEO destinations from which NASA, along 

with other customers, can purchase services and stimulate the growth of commercial 

activities in LEO. As commercial LEO destinations (CLDs) become available, 

NASA intends to implement an orderly transition from current International 

Space Station (ISS) operations to these new CLDs. Transition of LEO operations 

to the private sector will yield efficiencies in the long term, enabling NASA to shift 

resources towards other objectives. With the introduction of CLDs, NASA expects 

to realize efficiencies from the use of smaller, more modern and efficient platforms 

and a more commercial approach to meeting the Agency’s needs in LEO. In the 

longer term, the gradual emergence of additional customers for commercial LEO 

destinations will offer the opportunity for additional savings.

The extension of ISS operations to 2030 will continue to return benefits to the 

United States and to humanity as a whole while preparing for a successful transition 

of capabilities to one or more commercially-owned and -operated LEO destinations 

(CLDs). NASA has entered into a contract for commercial modules to be attached 

to a space station docking port and awarded space act agreements for design of 

three free-flying commercial space stations. U.S. industry is developing these 

commercial destinations to begin operations in the late 2020s for both government 

and private-sector customers, concurrent with space station operations, to ensure 

these new capabilities can meet the needs of the United States and its partners.
46

Working with NASA

Once a payload has been selected for development, engineering and operations 

staff in the ISS Program Office are available to work with payload teams through 

the design, test, certification, build, and launch phases prior to beginning mission 

operations on ISS. More detailed information on this process, and information on 

current and planned launch vehicles, is available at https://www.nasa.gov/mission_

pages/station/research/research_information.html. 

Potential proposers to any NASA program announcement should contact the 

relevant Program Scientist to discuss the appropriateness of their concepts for the 

specific solicitation and to determine who to contact within the ISS Program Office 

for discussing expected development costs for their proposal budgets.
47

BAD Broadcast Ancillary Data 

C&DH Command and Data Handling

CEPA Columbus External Payload Adapter

ECLSS Environmental Control & Life Support Systems 

EEU Experimental Exchange Unit

ELC EXPRESS Logistics Carrier

ESA European Space Agency

EVA Extravehicular Activity (spacewalk)

EXPRESS Expedite the Processing of Experiments for Space Station Rack 

FRAM Flight Releasable Attachment Mechanism

ICD Interface Control Document

ICU Integrated Communications Unit

ISS International Space Station

JEM Japanese Experiment Module 

JEM-EF JEM Exposed Facility

LEO Low Earth Orbit

LOS Loss of Signal

MCC Mission Control Center

MISSE Materials on International Space Station Experiment 

MSS Mobile Servicing System

NASA National Aeronautics and Space Administration 

PIM Payload Integration Manager

PL MDM Payload Multiplexer De-Multiplexer 

PRCU Payload Rack Checkout Unit

RIM Research Integration Manager

RMS Robotic Manipulator System

SE Safety Engineer

TDRSS Tracking and Data Relay Satellite System 

TEA Attitude Torque Equilibrium Attitude

TREK Telescience Resource Kit

TRL Technology Readiness Levels

WORF Window Observational Research Facility

Acronyms
48

The Complete ISS Researcher’s 

Guide Series

1. Acceleration Environment

2. Cellular Biology

3. Combustion Science

4. Earth Observations

5. Fluid Physics

6. Fruit Fly Research

7. Fundamental Physics

8. Gene Lab

9. Human Research

10. Macromolecular Crystal Growth

11. Microbial Research

12. Microgravity Materials Research

13. Physical Sciences Informatics Systems

14. Plant Science

15. Rodent Research

16. Space Environmental Effects

17. Technology Demonstration
49

For more information...

Space Station Science 

https://www.nasa.gov/iss-science

Station Research Facilities/Capabilities

https://www.nasa.gov/stationfacilities

Station Research Opportunities 

https://www.nasa.gov/stationopportunities

Station Research Experiments/Results 

https://go.nasa.gov/researchexplorer

Station Research Benefits for Humanity 

https://www.nasa.gov/stationbenefits

ISS Research Client Helpline

JSC-ISS-research-helpline@mail.nasa.gov

281-244-6187
50

National Aeronautics and Space Administration

Johnson Space Center

http://www.nasa.gov/centers/johnson

www.nasa.gov

NP-2022-06-009-JSC