Astronaut Christina Koch ends record-setting mission

Returns to earth from the intl. space station on Thursday

(FOX News)- NASA astronaut Christina Koch is returning to earth from the international space station and she's making history.

It was the longest single spaceflight by a woman.

It's also the second-longest single spaceflight by any U.S. astronaut.

She arrived at the station on March 14, 2019.

She's scheduled to return Thursday after 329 days, breaking Peggy Whitson's record of 288 consecutive days in space.

During her mission, Koch orbited the earth more than 52-hundred times, did six spacewalks and spent a total of 42 hours and 15 minutes outside the station.

The mission will help NASA prepare to go to mars.

NASA says it gives researchers a chance to observe the effects of long-duration spaceflight on a woman.