What Happens When the ISS Is Defunded: Controlled Descent or Relocation?

The International Space Station (ISS) currently plays a vital role in space research and international cooperation. However, questions arise about its future if it is defunded. Would the ISS be relocated to a long-term stable orbit, or would it undergo a controlled descent? This article explores these options and the practicalities behind them.

Why a Long-Term Stable Orbit Is Not Feasible

The International Space Station, weighing over 400,000 kilograms, is far too massive to be relocated to a stable orbit. According to NASA, the only viable option is a controlled re-entry to ensure safety and economic efficiency.

Current Depopulation and Descent Plan

The ISS will continue operation until around 2024, after which a series of re-entry engine burns will be conducted to bring the station to a remote part of the world's ocean. This method ensures a safe and controlled demise of the station without causing harm to inhabited areas.

Why Controlled Descent Is Preferred

Similar to Skylab, a controlled descent into the atmosphere is the preferred option for the ISS. The reasons are both safety and technical feasibility.

Uncontrolled Descent Risks

Leaving the ISS in its current orbit would expose it to residual atmospheric drag, which could lead to an uncontrolled re-entry. This would be risky not only for the station but also for any potential damage it might cause on re-entry. For this reason, a controlled descent is necessary.

Loss of Control and Reassembly Difficulty

Attempting to alter the ISS's orbit would be extremely challenging and potentially catastrophic. The ISS is a complex structure, consisting of multiple modules with various critical systems and external payloads. Adding rockets and attempting to propel such a massive structure would risk tearing it apart or causing it to spin out of control.

The Practicality of Relocation

The technical difficulties of moving the ISS outweigh the benefits. Dismantling the station, moving each part, and reassembling it in a higher orbit would be an astonishingly challenging task. The complexity and potential risks involved make this a non-viable option.

The Economic and Political Context

The ISS is a significant investment, costing approximately $50.4 billion as of 2016—equivalent to about $7.5 million per crew member per day. The political climate also plays a role, as the U.S. sanctions have reduced the support from Russia for transportation services to and from the ISS.

Implications of Reduced Support

Due to the ongoing conflict in Crimea, Russia has announced plans to reduce its support for ISS operations. This reduction in support further complicates the relocation or long-term maintenance of the ISS.

Future Steps and Contingencies

Given the technical and economic constraints, the controlled descent of the ISS is the most practical and safest option. The plan is to deorbit the ISS in 2024 and ensure it impacts a remote part of the ocean, complying with the guidelines set by the United Nations Outer Space Treaty.

Scientific Legacy and Public Awareness

Despite the end of the ISS's operational life, its legacy and contributions to science and international cooperation will be remembered. Efforts will continue to educate the public and the scientific community about the achievements of the ISS.

In conclusion, while the idea of keeping the ISS in a stable orbit is tempting, the technical and economic realities make a controlled descent the only feasible option. The ISS will be given a dignified end through a controlled re-entry, ensuring the safety of both the station and the environment.