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Feb. 8, 2018

ISS Transition

The NASA Authorization Act of 2017 provided for an International Space Station (ISS)

Transition Plan under section 303:

The Administrator, in coordination with the ISS management entity (as defined in section 2 of 

the National Aeronautics and Space Administration Transition Authorization Act of 2017), 

ISS partners, the scientific user community, and the commercial space sector, shall develop a 

plan to transition in a step-wise approach from the current regime that relies heavily on 

NASA sponsorship to a regime where NASA could be one of many customers of a low-Earth 

orbit non-governmental human space flight enterprise.

This document highlights the top-level policy elements of NASA’s ISS and low-Earth orbit 

(LEO) transition activities required to be included in the Congressionally authorized ISS 

Transition Report. NASA is currently developing the report, which is expected to be released 

this spring. 

Uses of a LEO Space Platform

Preparing for Human Deep Space Missions

In order to prepare for human expeditions into deep space, the Agency must first conduct 

breakthrough research and test the advanced technology necessary to keep crews safe and 

productive on long-duration space exploration missions. An on-orbit platform like the ISS is 

necessary to mitigate 22 of the 33 human health risks in the portfolio identified by NASA’s 

Human Research Program. NASA is also currently using the ISS as a testbed to fill critical gaps 

in technologies that will be needed for long-duration deep space missions. For example, 

elements of the ISS life support and other habitation systems will be evolved into the systems 

that will be used for deep space exploration missions and undergo long-duration testing. It is 

NASA’s plan to first develop and demonstrate many critical technology capabilities using the 

ISS as a permanently-crewed testbed prior to deploying these capabilities beyond LEO. This 

approach is much more cost-effective and faster than conducting this research in cislunar space 

because of the risks inherent in operating so far from the Earth.

Global Leadership in human spaceflight

The strength of the international partnership created through the ISS Program is a testament to 

U.S. leadership in space and to the aerospace expertise of all the nations involved. It serves as an

example of how many countries can work together to design, build, operate, and maintain large, 

complex human space assets. As we consider the future of ISS and potential successors and

prepare for human missions of exploration into deep space, it is important to consider how to

build on and improve these relationships as NASA proceeds into cislunar space. The ISS partner 

agencies are looking for leadership in human spaceflight and LEO from the U.S. Informally, all 
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of the partner agencies have indicated that they expect to continue cooperative activities with 

NASA.

Enabling LEO Commercialization

Through public-private partnerships centered around the ISS platform, NASA is enabling the 

development of a commercial space economy in LEO where NASA could be one of many 

customers. 

Under the Commercial Resupply Services (CRS) contracts, NASA’s two commercial cargo 

partners, Space Exploration Technologies (SpaceX) and Orbital ATK, have demonstrated not 

only the ability to provide cargo deliveries to ISS, but also the flexibility to recover effectively 

from mishaps. The addition of a third commercial service provider, Sierra Nevada Corporation,

will add significant on-orbit and return capability. Both Orbital ATK and Sierra Nevada 

Corporation have begun to investigate options to perform significant on-orbit operations after 

their primary cargo mission is completed. These two providers are able to provide an on-orbit 

research capability independent of ISS. NASA’s commercial crew partners, SpaceX and the 

Boeing Company, are developing the Crew Dragon and CST-100 Starliner spacecraft, 

respectively. These companies have made significant progress toward returning crew launches 

to the U.S., and NASA anticipates having these capabilities in place by 2019 to regularly fly 

astronauts safely to and from ISS. The crew and cargo vehicles, as well as the launch vehicles 

developed by these providers, have the potential to support future commercial enterprises as well

as ISS.

The Center for the Advancement of Science In Space (CASIS) manages the activities of the ISS 

National Laboratory to increase the utilization of the ISS by other Federal entities and the private 

sector. CASIS works to ensure that the Station’s unique capabilities are available to the broadest 

possible cross-section of U.S. scientific, technological, and industrial communities. The ISS 

National Laboratory is helping to establish and demonstrate the market for research, technology 

demonstration, and other activities in LEO beyond the requirements of NASA. 

Benefitting Humanity

Across a range of disciplines and applications, research on a crewed space platform ultimately 

benefits people on Earth. In the physical and biological sciences arena, a LEO space platform

can allow researchers to use microgravity conditions to understand the effect of the microgravity 

environment on microbial systems, fluid physics, combustion science, and materials processing, 

as well as environmental control and fire safety technologies. Technologies developed for use in 

space, such as water purification technologies, can have applications on Earth. Crewed 

platforms can also be the site of sensors that provide data used to support activities such as 

disaster relief.

Options for the Future

The NASA Transition Authorization Act of 2017 directed NASA to develop a plan to transition 

ISS from the current regime that relies heavily on NASA sponsorship to a regime where NASA 
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could be one of many customers of a LEO non-governmental human space flight enterprise. 

NASA has assessed options that support this vision for the future of human spaceflight in LEO. 

These options included: 

 Extending ISS beyond 2024 as-is;

 Revising the current ISS operating model to shift to a public-private partnership operating 

model where NASA could be one of many customers;

 Maintaining and transitioning elements and components of the ISS to a private platform;

and 

 De-orbiting portions of the ISS or the entire spacecraft.

Some of the key considerations in assessing these options are: 

 Whether alternative platforms for conducting necessary research and technology 

development are becoming available; 

 The cost of continuing ISS vs. the cost of enabling the development of new capabilities

that could meet NASA’s long-term LEO needs and the needs of others; 

 The interest among NASA’s International Partners to extend, change, or terminate the 

existing ISS arrangements; 

 NASA’s strategic human spaceflight leadership;

 The potential for different management approaches for the ISS to reduce its operating 

costs;

 Changes to the current assessment of the technical feasibility of extending the platform 

beyond 2024; 

 The demand outside of NASA in private industry and other Government agencies for 

LEO research capabilities;

 The amount of time required for ISS maintenance vs. research time; and

 The ability to add additional international participants thereby distributing costs. 

Beyond these considerations are broader national policy questions concerning the importance of 

an ongoing U.S. human presence in LEO, the foreign policy value of international collaboration 

on space exploration, and the role of the U.S. Government in that ongoing presence. 

NASA engages regularly with its International Partners, not only on the technical feasibility of 

extending the ISS, but on the policy considerations, alternative interests, and the importance of 

ensuring support for both LEO and future exploration activities. While each Partner is at a 

different stage in terms of considering the future of the ISS beyond 2024, NASA will continue to 

consult with the partnership regarding ISS transition in order to ensure consensus and the 

effective implementation of the ISS Program. 

The Path Forward

The Administration has evaluated the options and considerations described above, and is 

proposing several policy considerations. First, the benefits to U.S. foreign policy from 

international collaboration on space exploration can be continued and enhanced by learning from 
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the ISS partnership as we turn our focus to deep space exploration. The Administration is 

willing to deepen its collaboration with its allies while working with a broader range of partners 

of all levels of capability. 

Second, U.S. scientific and technical interests in LEO, which have been ably supported by the 

ISS, can also be supported by a diverse range of commercial LEO capabilities and operations. In 

support of enabling a timely development and transition of commercial capabilities in LEO 

where NASA could be one of many customers in the mid-2020s, the Administration is proposing 

to end direct Federal support for the ISS in 2025 under the current NASA-directed operating 

model, and is requesting $150 million in FY 2019 (with increasing investments in subsequent 

years) to enable the development and maturation of commercial entities and capabilities which 

will ensure that commercial successors to the ISS – potentially including elements of the ISS –

are operational when they are needed. It is the intent of NASA and the Administration to 

maintain seamless access to a human platform in LEO that meets NASA’s and the Nation’s 

goals.

Third, the Administration sees LEO and deep space exploration efforts as part of a cohesive U.S. 

exploration strategy. Regular access to a platform in LEO is essential for providing a stable 

space transportation infrastructure that benefits all exploration efforts; it is essential for 

developing, testing, and troubleshooting technologies needed for exploration before they are 

used in locations where failures pose a greater risk to mission success and human life; and it is 

essential to maintaining a robust scientific enterprise that continues to answer fundamental 

questions about the effects of microgravity on the human body and on the technology with which 

we surround ourselves.

The decision to end direct federal support for the ISS in 2025 does not imply that the platform 

itself will be deorbited at that time – it is possible that industry could continue to operate certain 

elements or capabilities of the ISS as part of a future commercial platform. NASA will expand 

international and commercial partnerships over the next seven years in order to ensure continued 

human access to and presence in LEO. 

Lastly the Administration strongly supports obtaining commercial industry’s ideas on ISS 

transition and the commercialization of LEO, and will offer a broad range of capabilities and 

approaches to seamlessly transition LEO activities to the private sector. The Administration will 

request market analysis and business plans from the commercial sector and solicit plans from 

commercial industry.

In the upcoming ISS Transition Report, NASA will further elaborate on encouraging the 

emergence of an environment in LEO where NASA is one of many customers of a nongovernmental human space flight managed and operated enterprise, while providing a smooth 

and uninterrupted transition.