The International Space Station (ISS), a collaborative effort between NASA and international partners, has been continuously occupied for nearly 25 years. As the station ages, NASA faces increasing risks and challenges in maintaining safe operations through 2030 and beyond. A recent audit by NASA’s Office of Inspector General examined the agency’s management of these risks, focusing on operations, maintenance, safety, and plans for the station’s eventual deorbit.
Structural Integrity and Aging Concerns
The ISS was designed and constructed nearly 30 years ago, with its structure having a finite lifespan. NASA continuously monitors the station’s ability to operate safely, incorporating a risk-based management approach. The U.S. segment of the ISS is currently certified through 2028, with efforts underway to extend certification to the end of the station’s life.
A significant concern is the ongoing issue of cracks and air leaks in the Russian Service Module Transfer Tunnel. While not an immediate risk to the station’s structural integrity, NASA and Roscosmos continue to investigate and mitigate these issues. In April 2024, NASA identified an increase in the leak rate to its highest level to date, elevating this risk to the highest level in its risk management system.
Maintenance and Supply Chain Challenges
As the ISS ages, maintaining and repairing its systems becomes increasingly complex. NASA spends approximately $1 billion annually on system operations and maintenance. The agency faces challenges in acquiring key replacement parts as suppliers decrease or cease production in anticipation of the station’s projected end of life in 2030.
NASA and its contractor, Boeing, conduct annual analyses to develop strategies for future operational needs, including anticipated parts replacement. While current strategies effectively meet operational needs, the ISS Program faces challenges with future parts availability through 2030 and potentially beyond.
Transportation Capabilities and Risks
Sustaining ISS operations relies heavily on reliable transportation capabilities for both cargo and crew. Currently, NASA primarily depends on SpaceX for cargo and crew transportation, with Northrop Grumman providing additional cargo services. The lack of redundancy and limited capabilities increase the risk to NASA’s ability to maintain safe operations and full utilization of the ISS.
Delays in certifying additional commercial transportation options, such as Sierra Space Corporation’s Dream Chaser and Boeing’s Starliner, further complicate the situation. The reliance on a single launch provider for both cargo and crew transportation poses a significant risk should that provider face grounding or failure.
Orbital Debris and Safety Concerns
The threat of micrometeoroids and orbital debris (MMOD) remains a top risk to crew safety and ISS operations. NASA mitigates this risk primarily through shielding and tracking. However, the agency has accepted some risk from MMOD and does not plan to add further protective exteriors due to high costs and technical challenges.
Transition and Deorbit Plans
NASA plans to transition operations to at least one commercial low Earth orbit destination prior to deorbiting the ISS in 2031. However, uncertainties surrounding the readiness of commercial destinations, limited budget availability, and potential delays in the U.S. deorbit vehicle development add challenges to this timeline.
The agency is working with international partners to update the deorbit plan, which currently relies on Russian propulsion capabilities. However, Russia has not yet committed to ISS operations through 2030, creating uncertainty around the ability to conduct a controlled deorbit.
Summary
As the International Space Station approaches the end of its operational life, NASA faces numerous challenges in maintaining safe operations through 2030. These include structural integrity concerns, maintenance and supply chain issues, transportation risks, and uncertainties surrounding the transition to commercial destinations and eventual deorbit. Addressing these challenges will require continued collaboration with international partners, strategic planning, and potentially significant funding to ensure the ISS can safely complete its mission and pave the way for future endeavors in low Earth orbit.
