The end of the International Space Station is finally approaching, with NASA declaring the retirement of the orbital outpost in 2030 and a dramatic deorbiting early in the following year.
Nothing lasts forever, not even the International Space Station. The writing’s been on the wall for some time now, but NASA made it official earlier this week, announcing that ISS operations will last until 2030 but no further. Upon retirement, the space station will perform a controlled re-entry and crash onto a remote part of the Pacific ocean known as Point Nemo. It’s all part of NASA’s plan to hand over space station responsibilities to the private sector and save a whole lotta cash in the process.
“The private sector is technically and financially capable of developing and operating commercial low-Earth orbit destinations, with NASA’s assistance,” Phil McAlister, director of commercial space at NASA, said in the statement. “We look forward to sharing our lessons learned and operations experience with the private sector to help them develop safe, reliable, and cost-effective destinations in space.”
In a detailed transition report sent to Congress, NASA said it expects to save $US1.3 ($1.8) billion the year after ISS is gone and $US1.8 ($2.5) billion per year by 2033. The space agency plans to spend these estimated savings on deep space exploration projects, allowing it to “explore further and faster into deep space,” according to the report. But by extending the mission to 2030, NASA will “continue another productive decade of research advancement and enable a seamless transition of capabilities in low-Earth orbit to one or more commercially owned and operated destinations in the late 2020s.”
In an email, Jonathan McDowell, an astronomer from the Harvard-Smithsonian Centre for Astrophysics, cautioned that the new report didn’t include claims that other ISS partners, such as Russia, will agree to sustain ISS until 2030, “so it could be sooner,” he explained. Fair point. Russia, it would appear, has already checked out, as evidenced by threats of leaving and the deteriorating state of its ISS assets.
ISS has been in orbit since 2000, hosting a continuous succession of astronauts throughout its 22-year history. It’s the largest orbital outpost ever built — a stunning collaboration involving 15 different countries. Late last year, the Biden administration quietly extended the station’s lifetime from 2024 to 2030, but as the new report points out, this mission extension represents the last.
In its plan, NASA describes the decommissioning process, including a potential strategy to detach some modules and attach them to other space stations. At some point in 2030, the final crew will have to depart the ISS, in what will be undoubtedly an emotional and historic moment.
In early 2031, and with no one onboard, controllers will use thrusters to lower the station’s altitude to just above Earth’s atmosphere. The ISS will then make its fatal plunge through the atmosphere, followed by bits of debris splashing down onto the South Pacific Oceanic Uninhabited Area (SPOUA) in the vicinity of Point Nemo. This spot carries the nickname “spacecraft cemetery,” as it’s where space agencies have plopped hundreds of space pieces, including Russia’s Mir space station, for the past 50 years. Point Nemo is nowhere near inhabited areas, the closest being 2,690 km away.
Sounds simple, but the required degree of precision will require some extra work. The challenge is that ISS isn’t equipped with a big enough engine to allow direct travel from its current position to its required final low orbit in a single burn, as McDowell explained. ISS operators will have to “lower its orbit in stages before the final burn,” he said. “But you can’t lower it too far or the drag (winds) will make you lose attitude control and the station will start to tumble because of the forces.” The station will have to be lowered far enough before making the final burn, requiring the use of two Russian Progress spacecraft to lower the orbit and “then a third one to dump it,” McDowell said.
Indeed, and as NASA explains in its report, the station will “accomplish the de-orbit manoeuvres by using the propulsion capabilities of the ISS and its visiting vehicles,” namely Progress and possibly Cygnus spacecraft. Then, “after performing manoeuvres to line up the final target ground track and debris footprint” above SPOUA, ISS operators “will perform the ISS re-entry burn, providing the final push to lower ISS as much as possible and ensure safe atmospheric entry,” according to the report.
With the end of the ISS firmly in sight, NASA will be turning to the private sector to maintain a continuous human presence in space. To that end, NASA has already allocated $US415.6 ($582) million as part of its Commercial Low Earth Destinations program, with the funds being distributed to Blue Origin, Nanoracks, and Northrop Grumman. There is concern, however, that space stations built by these firms won’t be ready in time and that a gap will exist by the time ISS is retired a mere eight years from now.
This situation could get worse if, as McDowell warned, other ISS partners won’t commit to the 2030 extension. Russia, like China, has plans to build its own space station in the coming years. It seems we’re at the end of an era. Fair to say, an international collaboration like this won’t happen any time soon.