JIUQUAN, May 23 (Xinhua) -- An astronaut from the Shenzhou-23 crew to be launched to space Sunday is set to carry out a one-year-long in-orbit stay experiment, the China Manned Space Agency (CMSA) said on Saturday.

Photo: CMG

Chinese astronauts Zhu Yangzhu, Zhang Zhiyuan and Li Jiaying, or Lai Ka-ying in Cantonese, will carry out the Shenzhou-23 crewed spaceflight mission. The astronaut selected for the year-long stay will be determined based on how the mission unfolds in orbit, CMSA spokesperson Zhang Jingbo said at a press conference.

During the year-long residency, China will implement its first space-based human body research program to collect crucial data on astronaut exposed to long-duration spaceflight environments, Zhang noted.

"Assigning an astronaut to a one-year in-orbit stay is not simply doubling the duration of two six-month missions," said Zhang.

The extended mission will test health support capabilities for astronauts on long-duration missions, while upgrading in-orbit medical and protection systems, according to Zhang.

It will also provide opportunities for long-term continuous research on scientific projects and related technology verification, said Zhang.

The Shenzhou-21 crew, now up for rotation, has already spent 203 days in orbit and is poised to set a record for the longest single mission duration by a Chinese astronaut crew so far.