The nation’s first astronaut, Yi Soyeon, attended a welcoming event for her and her fellow Soyuz astronauts who returned from a trip to space last month.

Yi said that she is in good health at the event held at the Star City training center outside Moscow on Friday.

She added that she has a slight backache and needs some more medical treatment. But Yi believed that she will be feeling better soon.

U.S. astronaut Peggy Whitson and Russian cosmonaut Yuri Malenchenko also attended the event.

A Russian spaceship expert said that an investigation is under way to find what the technical glitch was that caused the rough landing of Russia's Soyuz TMA-Eleven capsule carrying Yi last month.