A combination of 11 astronauts and cosmonauts currently make up the largest crew in more than a decade aboard the International Space Station, or ISS, after four NASA, European and Japanese astronauts arrived at the orbiting laboratory on April 24. They joined seven astronauts and cosmonauts who have been living and working on orbit for several months.
The ISS normally can house a crew of seven. This overlap of about a week between arriving and departing crews prompted NASA and Boeing to evaluate the best way to make sure everyone had a safe place to sleep and other resources.
The ISS is as large on the inside as an empty 747 airliner, with plenty of room for the crews to live relatively comfortably while accomplishing scientific research and related tasks.
The seven regular crew members have their own private spaces in the ISS complex, including sleeping quarters recently set up in the Columbus laboratory module. Additional crew members typically sleep inside the spacecraft they arrived in. But before any of them got their zzz’s, Boeing engineers completed several weeks of detailed studies to ensure everyone would be safe.
“It’s something that can’t be taken for granted, because air doesn’t behave in microgravity the way it does on Earth,” said Dr. Chang Son, Boeing’s lead for ISS life support system analysis. “In space, the airflow dynamics are more complicated and ventilation in small enclosures is of particular concern. We have to make sure the airflow velocity is adequate to prevent pockets of carbon dioxide from building up.
“We did these analyses of the Columbus module and other areas on a compressed timeline,” Son continued, “and when they were complete, we could tell NASA that the sleeping areas are safe for the crew.”
Evaluations like this are normal business for the Boeing teams that have worked hand-in-glove with NASA since before the first ISS module was launched in 1998. Along with the recent sleep area studies, Boeing engineers have evaluated everything from the movements of the 55-foot-long (16.7 meters) robotic arm on the ISS to surveys of the station’s structure and systems.
That deep knowledge enables mission engineers and planners to continue operating the ISS for many years to come. It also demonstrates the information and resources that will be needed for future crews as they set out for deep-space destinations such as the Moon and Mars.