The 40-year-old Michigan native is already aboard the International Space Station, having arrived there March 14, and will remain in orbit until February 2020. That will give her a 328-day stint aboard the ISS.
"It feels awesome," Koch said of her extended mission in a video shot aboard the ISS and posted by NASA on Wednesday. "I have known that this was a possibility for a long time, and it's truly a dream come true."
If Koch remains on the ISS as planned, she will break the record for the single longest spaceflight by a woman of 288 days set by retired astronaut Peggy Whitson in 2017. She'll fall short of the all-time record for a single spaceflightof 340 days set by former astronaut Scott Kelly in 2016.
The announcement comes weeks after Koch was in the news as a result of NASA's controversial decision to cancel its first all-female spacewalk. Koch had been scheduled to venture outside the space station with fellow astronaut Anne McClain on March 29, but the space agency changed the spacewalk assignments because only a single medium-size spacesuit was available.
Koch wound up doing the spacewalk with astronaut Nick Hague. McClain's spacewalk was rescheduled for a later date.
As it prepares to send astronauts back into deep space, NASA is looking to learn more about the effects of long-duration spaceflight on the human body.
"NASA is looking to build on what we have learned with additional astronauts in space for more than 250 days," Jennifer Fogarty, chief scientist of the Human Research Program at NASA's Johnson Space Center in Houston, said in a written statement. "Christina's extended mission will provide additional data for NASA's Human Research Program and continue to support future missions to the moon and Mars."
Koch certainly seems eager to help. "One month down. Ten to go," she said in a tweet. "Privileged to contribute my best every single day of it."
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