All good things must come to an end. That is also true for the International Space Station, which has served as an outstation for humanity in low-Earth orbit for nearly a quarter of a century. Now, NASA is developing a plan to deorbit the space station as it comes to the end of its life.
Currently, the ISS is scheduled to end its lifetime in 2030. NASA, the Canadian Space Agency, and the European Space Agency have committed to operating the space station till 2030. Russian space agency Roscosmos, meanwhile, has committed to the space station only till 2028.
The 109-metre-wide space station is a little too big to get completely vapourised in the Earth’s atmosphere during reentry. This is why NASA plans to send a spacecraft to tug the space station and deorbit it in such a manner that it reenters over the South Pacific Ocean. The space agency plans to spend up to $1 billion on this tug, reported SpaceNews in March this year.
NASA in September requested ideas from the US aerospace industry to build the “US Deorbit Vehicle” (USDV). “The USDV is focused on the final deorbit activity. It will be a new spacecraft design or modification to an existing spacecraft that must function on its first flight and have sufficient redundancy and anomaly recovery capability to continue the critical deorbit burn. As with any development effort of this size, the USDV will take years to develop, test, and certify,” said a statement from the agency.
While the space agency’s life is only set to end in 2030, it is already a delicate matter for aerospace engineering and international diplomacy, according to Scientific American. Even though it is supported by Canada, Japan and Europe, ISS is mainly a creation of the United States and Russia. Crucially, it is also one of the very few areas where the two countries continued to cooperate through periods of poor relations.
Till recently, NASA said that it might take many Russian Progress spacecraft working together to deorbit the space station. But that plan has always been a bit ambitious because of the difficulty of coordinating multiple spacecraft for the deorbiting manoeuvre. That would have been a challenge even when things were going well.
But following Russia’s invasion of Ukrainethings are not going well. The former’s relationship with the United States is arguably at its worst since the Cold War. This is also straining their collaboration on the International Space Station.
To make things trickier, a spate of recent incidents has called Russia’s capabilities in space into question. There have been many incidents caused by Russian-built hardware on the space station. This includes multiple leaks on the International Space Station. The Roscosmos-led Soyuz MS-10 mission carrying astronauts to ISS in 2018 had to be aborted shortly after launch. Much more recently, Luna-25, the country’s first lunar mission in nearly half a century, crashed on the Moon.
All of these factors together give NASA enough reasons to develop an American deorbiting vehicle. While the space tug is expected to cost $1 billion in total, the space agency requested $180 million for the fiscal year 2024 to start developing the technology, according to SpaceRef. The White House also requested initial funding for the space tug to meet “critical domestic needs.”
“The funding will help ensure continued US leadership in space, especially as we plan for the safe transition of our operations in low Earth orbit to commercial-owned and operated platforms that continue access and presence in space for research, technology development and international collaboration,” said NASA administrator Bill Nelson in an email to SpacePolicyOnline.
Technically, the deorbiting of the International Space Station may be the joint responsibility of five entities. But it seems like once again, the United States is set to take leadership on a space mission.