Three ISS astronauts return safely to Earth after spending 168 days in orbit and completing hundreds of experiments

Three members of the International Space Station Expedition 55 crew returned safely to Earth on 3 June after nearly half a year-long stint in space.

File image of International Space Station. Reuters

American astronaut Scott Tingle, Japanese astronaut Norishige Kanai and Russian cosmonaut Anton Shkaplerov had lived and worked in a low-Earth orbit for 168 days.

"Touchdown! @Anton_Astrey, @Astro_Kanai and @Astro_Maker are back on Earth after parachuting to a landing in Kazakhstan today at 8:39am ET (6:39pm Kazakh time)," International Space Station said in a tweet.

Expedition 55 Flight Engineers Tingle, Kanai and Shkaplerov undocked from the International Space Station at 5:16 a.m. EDT to begin their trip home, NASA said in a blogpost.

This mission was the first for Tingle and Kanai, and Shkaplerov now has logged 532 days in space on three flights.

The crew completed hundreds of experiments, including materials testing, a study of the effect of microgravity on the bone marrow and research into plant growth in space.

Tingle and Kanai ventured outside the station on separate spacewalks to perform work on parts of the Canadarm2 robotic arm.

They also participated in dozens of educational events as part of NASA's Year of Education on Station.

Shkaplerov conducted a record-setting spacewalk in February with fellow cosmonaut Alexander Misurkin to replace an electronics box for a communications antenna on the Zvezda service module.

The spacewalk timed out at 8 hours and 13 minutes — the longest in Russian space program history.

The Expedition 56 crew -- Commander Drew Feustel and Ricky Arnold of NASA, and Oleg Artemyev of Roscosmos -- will operate the station and prepare for the arrival of three new crew members on June 8.