Retirement of the International Space Station
Image of the ISS taken in orbit. Credits: ESA
The International Space Station (ISS) is one of two science laboratories currently in orbit around Earth (the other one being the Chinese Tiangong space station). Travelling at 28,000 km/h (17,500 mph) at an average altitude of 400 km (240 miles), the ISS is a collaboration between NASA, Roscomsos, ESA, JAXA and CSA, and serves as a tool for learning how to live in space and the prolonged effects of the space environment on the human body.
Since its completion in 2009, a total of 251 individuals from 19 countries have visited the ISS, and since November 2020, it has been continuously inhabited.
The ISS serves many purposes, possibly the most important one being scientific research. Many experiments are conducted onboard the station in a wide range of fields such as astronomy, astrobiology, human research and meteorology. The ISS is a particularly interesting place to conduct research as it is the only laboratory that offers continuous microgravity and exposure to the space environment.
Comet Lovejoy photographed by astronaut Dan Burbank onboard the ISS. Credits: NASA
As there are routinely scheduled launches planned to resupply the station, astronauts are regularly sent hardware or tools relative to the experiments they are conducting.
Another important role the ISS has played over the years is being a platform for student research investigations and educational outreach. In 2020, CASIS released a report where it explains how beneficial it has been to allow STEM (Science, Technology, Engineering and Mathematics) students of various ages to be involved in the experimentation conducted in orbit. They have also stated that:
"Over the past 20 years, 2.6 million U.S. K-12 students have participated in experiments using the ISS."
And it is true that there is something mesmerising about space that catches the attention of everyone, even those who are not involved in sciences.
The retirement plan
NASA released in this International 2021 Space Station Transitional Report that the de-orbiting of the ISS is scheduled to take place in January 2031 in the South Pacific. This portion of the ocean was chosen as it is large and inhabited. Moreover, it has served as a spacecraft graveyard for over 273 cargo crafts, space stations and transfer vehicles since the early 1970s.
The image below shows the area in which spacecrafts have de-orbited along with point Nemo: the point on Earth which is farthest from land. This point is so remote that the closest humans are actually the astronauts onboard the ISS.
Space graveyard. Image credit: Leo Delauncey / Mallonline
In 2001, Russia de-orbited its Mir space station, which at the time was the largest spacecraft in orbit. As the station re-entered the atmosphere, the pressure and temperature were high enough to completely disintegrate most of its parts. Some of the station's largest components, however, managed to crash into the ocean, leaving behind a trail as long as 2900 km.
Plans for the future
According to the Outer-Space Treaty, each country is legally responsible for de-orbiting its segments of the ISS. Therefore, each agency has a different plan of its own.
In the same report released by NASA, the agency detailed its plans for the ISS within the next decade. Specifically, it details that privately-owned space stations would replace the ISS for scientific research and in-orbit destinations.
“The private sector is technically and financially capable of developing and operating commercial low-Earth orbit destinations, with NASA’s assistance. 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” said Phil McAlister, director of commercial space at NASA Headquarters in a statement.
It has been clear for some time now that NASA has redirected its focus toward the Moon, with there being plans to send humans to the lunar South-Pole by 2025 with the Artemis program. Moreover, by 2028, they plan for humans to have a continuous presence on the moon.
If this sparks your interest, feel free to check out this video of NASA going over the program.
Russia's Roscosmos on the other hand has plans to build a new Russian Orbital Service Station (ROSS). Although it was originally planned that Roscosmos would reuse some parts of the ISS to build its own station, this original idea was later scrapped and instead they opted to build ROSS from scratch. Look out in the near future for any news, as the first launch is scheduled to take place in 2025, and the first crewed mission in 2026.
The second stage of the ROSS deployment (after 2030). Credits: ru:N+1
Although the end of the ISS is soon and inevitable, it is unclear if we will see another NASA/ESA/JA