Russian cosmonauts Sergey Ryzhikov and Sergey Kud-Sverchkov and NASA astronaut Kate Rubins will complete their 185-day mission to the space station on Friday.
Their departure in the Soyuz MS-17 spacecraft is broadcast live on NASA’s TV channel and website. The hatch closed on their spacecraft on Friday night after the crew bid farewell to the others on the station, and they pulled away from the station’s Poisk port at 9:34 p.m. AND.
The trio will land at 12:56 am Saturday on the Kazakhstan steppe.
The cosmonauts will return to their training base in Star City, Russia, and Rubins will return home to Houston.
Together, the time the crew spent on the station encompassed 2,960 Earth orbits and 78.4 million miles after their arrival in October.
Lots of time aboard the space station
It was the second flight for Rubins, meaning she has now spent 300 days in space, and the second flight for Ryzhikov helped her reach 358 cumulative days. Kud-Sverchkov experienced his first space flight.
This second spaceflight experiment for Rubins included hundreds of hours of working on space station experiments. She has also served as a science ambassador on calls to the space station with the National Science Foundation, the National Institutes of Health, and the United States Centers for Disease Control and Prevention, among others.
She was the first person to sequence DNA in space in 2016 and continued this work with more sequencing during her second stay on the space station. This ability could allow astronauts to diagnose illnesses in space or even identify microbes that thrive on the space station to determine if they pose any risk.
She collected samples from different locations on the space station to understand the space station’s microbiome. (The microbiome is the genetic material of bacteria, viruses, and other microbes that live inside the space station, including inside its residents.)
This unique environment has welcomed the comings and goings of hundreds of astronauts for 20 years while remaining separate from Earth.
Rubins has also worked on cardiac research to study the effects of gravity on cardiovascular cells and has grown and harvested radishes to create a better understanding of plant growth in the absence of gravity.
Seven crew members remain
The departure of Rubins, Ryzhikov and Kud-Sverchkov leaves the space station with seven crew members.
This includes new NASA astronaut Mark Vande Hei and Russian cosmonauts Oleg Novitskiy and Piotr Dubrovnik, as well as the crew of NASA’s historic SpaceX Crew-1 mission that arrived in November. They are NASA astronauts Victor Glover Jr., Michael Hopkins and Shannon Walker, and JAXA (Japan Aerospace Exploration Agency) astronaut Soichi Noguchi.
April is a busy time on the space station, and it feels a bit like a revolving door when crews arrive and depart.
On April 22, the space station’s occupancy rate is expected to rise to 11 when members of NASA’s SpaceX Crew-2, including NASA astronauts Shane Kimbrough and Megan McArthur, JAXA astronaut Akihiko Hoshide and European Space Agency astronaut Thomas Pesquet will arrive.
Space station astronauts prepared for the new crew by installing additional sleep stations and freeing up ports for the arrival of new spacecraft.
Next, Crew 1 is scheduled to return to Earth on April 28, again leaving the space station with seven crew members.