China's Shenzhou XIII mission crew is scheduled to carry out their second extravehicular activity, or spacewalk, on Sunday, according to the China Manned Space Agency.

Major General Zhai Zhigang, the mission commander, and Senior Colonel Ye Guangfu will conduct the spacewalk while Senior Colonel Wang Yaping will stay inside the Tiangong space station to support the extravehicular operations, the agency said in a brief statement on Saturday afternoon.

The Shenzhou XIII mission was launched on Oct 16 by a Long March 2F carrier rocket that blasted off from the Jiuquan Satellite Launch Center in northwestern China's Gobi Desert, with the crew soon entering the Tiangong space station. They are scheduled to spend six months working in the station, making it China's longest space mission.

By now, the astronauts have traveled in the space for 71 days. They are in good condition and are ready to perform the spacewalk, the agency said.

The mission crew completed its first spacewalk on Nov 8, with Wang, 41, becoming China's first female spacewalker.

During the 6.5-hour operation, Zhai and Wang mounted new components on the station's robotic arm and used the arm to practice extravehicular maneuvers. They verified the arm's capabilities and its compatibility with the needs of astronauts, examined the safety and performance of support devices and also tested the functions of a new type of extravehicular suit.

Shenzhou XIII is the fourth spacecraft to visit the Tiangong station, and also the second crewed ship to transport astronauts to the orbiting outpost.

One of China's most challenging and sophisticated space endeavors, Tiangong, or Heavenly Palace, will eventually consist of three main components-the Tianhe core module attached to two large space labs-with a combined weight of nearly 70 metric tons. The entire station is set to work for about 15 years in a low-Earth orbit about 400 kilometers above the planet.

The first astronauts inside Tiangong-Major General Nie Haisheng, Major General Liu Boming and Senior Colonel Tang Hongbo-finished their 92-day mission in mid-September. They performed two spacewalks.