Four astronauts aboard a SpaceX Crew Dragon capsule are scheduled to touch down early Thursday in the Pacific Ocean, ending a weeklong effort to bring an unnamed crew member home for evaluation of a medical issue.
The crew departed the International Space Station at 5:20 p.m. EDT on Wednesday aboard the spacecraft. They are on a 10-hour flight, gradually decreasing in altitude and preparing to reenter Earth’s atmosphere.
The Crew Dragon capsule separated from the International Space Station on Wednesday. -NASA
The astronauts, part of a mission called Crew-11, are scheduled to land at about 3:40 a.m. ET on Thursday off the coast of California.
NASA made the decision to bring the crew home last week after announcing that it had canceled a scheduled spacewalk due to a medical issue.
“This is not an injury that occurred during follow-up operations,” Dr. James Polk, chief health and medical officer at NASA Headquarters, said during a Jan. 8 news conference.
Rather, the problem is related to the presence of “a medical problem in difficult areas.” MicrogravityPolk added, noting that NASA wanted to bring the astronaut home to utilize diagnostic tools, and while the International Space Station has an array of medical equipment, it does not have all the tools that a typical emergency room would have.
The canceled spacewalk was performed by NASA’s Mike Finke and Zena Cardman, both members of Crew-11. The duo returns home alongside colleagues Kimiya Yui from the Japan Aerospace Exploration Agency (JAXA) and Russian cosmonaut Oleg Platonov from Roscosmos.
NASA has not identified any crew member with the medical problem, and the agency has not released details about the nature of the crewmate’s condition other than to say the person is in stable condition and will not need special arrangements for the return flight. Medical information is usually kept confidential to ensure the astronaut’s privacy.
Back to earth
The journey home can take a toll on astronauts’ bodies; The gravitational forces experienced as the Crew Dragon capsule returns toward Earth can reach more than five times the force of Earth’s gravity.
The final stretch of the mission is also among the most dangerous as the Crew Dragon capsule reenters the atmosphere at more than 22 times the speed of sound. This process can heat the exterior of the reentry spacecraft to more than 3,500 degrees Fahrenheit (1,926 degrees Celsius), leading to plasma buildup and causing a communications blackout.
After the capsule falls into the Pacific Ocean, rescue ships will wait nearby to pull it out of the water. Once aboard, crew members will likely exit their capsule on medical stretchers — a common practice for transporting astronauts when they return to Earth and begin readjusting to gravity. The use of a stretcher is not an indicator of whether an astronaut has a serious medical condition.
But NASA said that the injured astronaut will undergo a medical examination upon his return to Earth.
Who stayed on board the space station?
Crew-11 was originally scheduled to leave the space station in mid-February, only after a replacement team — the Crew-12 astronauts — arrived to take over operations.
The early departure of the Crew-11 astronauts leaves the football field-sized space station with three employees: two Russian cosmonauts, Sergei Kud-Sverchkov and Sergei Mikayev, as well as NASA astronaut Chris Williams, who traveled to the orbiting laboratory as part of a ride-sharing agreement with Russia.
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