China plans to launch the Shenzhou XIII manned spacecraft early on Saturday morning, carrying three astronauts who will stay inside the country's Tiangong space station for six months, one of the lead officials in the country's manned space program said.
Lin Xiqiang, deputy director of the China Manned Space Agency, said at a news conference on Thursday afternoon at the Jiuquan Satellite Launch Center in northwestern China that the mission will also feature the first spacewalk by a Chinese woman.
It is expected to become the longest space journey by Chinese astronauts, doubling the time of their peers in the Shenzhou XII mission.
The Shenzhou XIII spacecraft is scheduled to be launched at 12:23 am Saturday by a Long March 2F carrier rocket at the Jiuquan center, Lin said. It will transport Major General Zhai Zhigang, the mission commander, Senior Colonel Wang Yaping and Senior Colonel Ye Guangfu to Tiangong's core module Tianhe, or Harmony of Heavens.
Wang is China's second female astronaut to participate in a spaceflight and was a member of the Shenzhou X mission in June 2013. She will become the first Chinese woman to enter the Tiangong space station and conduct a spacewalk, Lin said.
Zhai is the country's first astronaut to take a spacewalk, having done so when he was mission commander during the Shenzhou VII mission in September 2008. Ye will be making his first journey to space on Saturday.
Lin said the Shenzhou XIII crew is tasked with a wide range of tasks, including performing two to three spacewalks to install a small robotic arm onto a larger one; verifying key procedures and technologies such as the manual control of the robotic arms and the robotic arm-assisted movement of station modules; checking the performance and capability of devices inside the station; and testing support instruments for astronauts' lives and work during long-term flights.
He added that they will conduct scientific experiments and technology demonstrations in space medicine, microgravity physics and other fields.
Liquid propellants have started to be injected into the rocket that will carry the astronauts to space, according to Lin.
Shenzhou XIII will be the fourth spacecraft to visit China's permanent space station — named Tiangong, or Heavenly Palace — and the second crewed ship to transport astronauts to the orbiting outpost.
The first astronauts inside Tiangong — Major General Nie Haisheng, Major General Liu Boming and Senior Colonel Tang Hongbo — finished their 92-day Shenzhou XII mission in mid-September.
They flew 90 days with Tiangong and made two spacewalks to use a large robotic arm and other equipment to install and adjust devices outside the station. They also performed a number of scientific experiments and technological tests and made video calls with President Xi Jinping and hundreds of researchers, teachers and students in Hong Kong.
One of China's most challenging and sophisticated space endeavors, Tiangong will consist of three main components — a core module attached to two space labs, with a combined weight of nearly 70 metric tons. The entire station is expected to operate for about 15 years in a low-Earth orbit, about 400 kilometers above the planet.
The station's core module Tianhe was lifted by a Long March 5B heavy-lift rocket at the Wenchang Space Launch Center in Hainan province in late April.
The craft is now connected with the Tianzhou 2 unmanned cargo ship that was launched from the Wenchang facility in late May, and the Tianzhou 3, another unmanned cargo ship that was lifted from Wenchang last month.
The biggest and heaviest spacecraft China has ever constructed, Tianhe is 16.6 meters long and has a diameter of 4.2 meters. The craft's weight, at 22.5 tons, is equal to the combined weight of 15 standard-size automobiles. It has three parts: a connecting section, a life-support and control section, and a resources section.
In 2022, two large space labs will be launched to connect with the core module. Moreover, two manned missions and two robotic cargo flights will be made that year to continue construction of the Tiangong station, which is scheduled to become complete and start formal operation around the end of 2022.
Upon its completion, Tiangong will be manned regularly by groups of three astronauts in periods lasting several months. During handovers to new three-astronaut groups, the station will accommodate up to six astronauts.