240 days in space: Is Sunita Williams aboard the Boeing Starliner setting a new record?

NASA astronaut Sunita Williams (Photo Credit - NASA)

Astronauts  Sunita Williams and Butch Wilmore will remain on the International Space Station (ISS) until at least February 2025, NASA announced on Saturday, August 24. This extends their mission by more than eight months beyond the original schedule. Initially signed up for an eight-day journey, the duo now faces an extended adventure in the cosmos.

The decision to delay their return stems from unresolved issues with the Boeing Starliner spacecraft, which carried them to the ISS. Instead, their journey back to Earth will be aboard a SpaceX vehicle, though a precise date for the return remains uncertain. Should everything proceed smoothly, the earliest possible return would be in early February, marking at least 240 consecutive days in space. A later departure, perhaps in March, could extend their stay to nearly 270 days.

Record-Holding Space Sojourns

The record for the longest consecutive days in space by an American astronaut is held by Frank Rubio, who spent 371 days aboard the ISS between September 2022 and September 2023. Rubio’s stay was extended well beyond its planned end date in March 2023 due to a mishap when a meteoroid or piece of space debris struck the Russian Soyuz spacecraft meant to bring him home. This left Rubio, alongside Russian cosmonauts Sergey Prokopyev and Dmitri Petelin, waiting an additional six months for a replacement spacecraft. Although Prokopyev and Petelin also endured 371 consecutive days in space, they fell short of breaking any Russian records. That honour belongs to cosmonaut Valeri Polyakov, who spent 437 consecutive days aboard Russia’s Mir space station from January 1994 to March 1995, which is a record for the longest continuous space mission by any human. Polyakov’s mission was a voluntary effort to study the effects of long-term spaceflight on human health.

Other notable long-duration space missions include Christina Koch’s 328 days aboard the ISS from March 2019 to February 2020, which set the record for the longest single spaceflight by a woman, and Scott Kelly’s 340 days in space from March 2015 to March 2016.

Space’s Toll on the Human Body

Extended stays in space are not without significant challenges. Scott Kelly’s near-year-long mission was part of NASA’s pioneering twins study, which compared the health of Kelly, who was in space, with his identical twin brother, Mark Kelly, who remained on Earth. This research revealed various changes astronauts undergo during prolonged space missions, including alterations in gene expression, body weight, and the gut microbiome. These findings contribute to a growing body of research indicating that long-term exposure to microgravity can lead to temporary health impacts such as muscle and bone loss, vision issues, reduced immunity, increased risk of blood clots, inflammation, and DNA damage. Thankfully, most of these changes tend to reverse after six months back on Earth. However, the full impact of long-duration space travel on human health is still being studied.

As Wilmore and Williams continue their extended mission, they may experience some of these physical changes, alongside potential mental health effects related to isolation and monotony. Yet, despite the challenges, their prolonged stay aboard the ISS is a safer alternative than returning on a spacecraft with unresolved technical issues.

The Starliner’s Troubles

On its journey to the ISS in June, the Boeing Starliner encountered multiple hydrogen leaks and issues with some of its smaller thrusters. While the craft managed to dock safely, subsequent tests have not resolved the problems satisfactorily. As a result, NASA officials announced on 24th August that the Starliner would undock from the ISS without its crew in early September, returning to Earth empty. Meanwhile, Wilmore and Williams will await their return trip aboard a more reliable SpaceX vehicle, slated for 2025.

This extension may be unplanned, but it adds another chapter to the storied history of human space exploration, demonstrating both the resilience of astronauts and the ever-present challenges of venturing beyond our planet.