Three ISS Crew Return to Earth, Record-Breaking NASA Astronaut Peggy Whitson Takes Command of Space Station

The International Space Station's (ISS) former Expedition 50 commander Shane Kimbrough returned to Earth today, April 10. This homecoming left the space station under the command of NASA astronaut Peggy Whitson.

Three crewmembers left the ISS after spending 173 days in space. Their capsule landed in Kazakhstan at 7:20 a.m. Kimbrough traveled back to Earth with Roscosmos astronauts Sergey Ryzhikov and Andrey Borisenko. The three astronauts were joined by tons of experiments on their trip back home.

One of their most popular experiments is the microgravity expanded stem cell investigation, which observed cell growth in microgravity. This is vital because it might eventually lead to treatment for space diseases and injuries, which are important for longer deep space flights such as the journey to Mars.

Commander Shane Kimbrough spent 189 days in space, while Borisenko clocked in 337 days and Ryzhikov with 173 days.

With Kimbrough back home, the leadership was transferred to female astronaut Peggy Whitson. Oleg Novitsky of Roscosmos and Thomas Pesquet of the European Space Agency (ESA) support Whitson while waiting for two more crewmembers to arrive at the ISS.

NASA astronaut Jack Fischer and Fyodor Yurchikhin of Roscosmos are scheduled to launch for the ISS this coming April 20. With Whitson manning the space station, she broke another world record being the first female astronaut to lead the ISS twice, according to a report.

"Moments ago @AstroPeggy broke yet another record when she became the first woman to command the space station twice!," a NASA official said in a Tweet.

The remarkable Peggy Whitson has other records under her belt. She is expected to break the record for the longest cumulative days spent in space -- a total of 534 days. A record currently held by a male counterpart, Jeff Williams. Whitson is expected to break the record on April 24.

NASA and Roscosmos agreed to extend Whitson's duty aboard the ISS. The female astronaut will remain in space until September.