The Shenzhou XI manned spacecraft was scheduled to dock with the Tiangong II space lab in the early hours of Wednesday morning as astronauts start their busy, monthlong schedule, the space authority said.

After nearly two days of spaceflight, the Shenzhou XI will conduct a computer-controlled docking with the space lab. Then the two astronauts－49-year-old Jing Haipeng and 37-year-old Chen Dong－will enter the lab and start the longest space stay by Chinese astronauts, according to the China Manned Space Agency.

During their 30-day mission in Tiangong II, the astronauts will carry out scientific experiments and research, including medical ultrasound examinations, weightlessness effects on cardiovascular functions and cultivation of plants as well as in-orbit repair, said Wu Ping, deputy director and spokeswoman for the agency.