Three Chinese astronauts have embarked on a six-month mission to complete construction of the nation's <a href="https://www.thenationalnews.com/world/asia/2022/04/16/chinese-astronauts-return-to-earth-after-record-space-mission/" target="_blank">Tiangong space station</a>. Astronauts Chen Dong, Liu Yang and Cai Xuhe entered the <a href="https://www.thenationalnews.com/uae/2022/02/02/chinese-astronauts-celebrate-lunar-new-year-in-space/" target="_blank">Tianhe core module</a> on Sunday in a key phase in China's efforts to expand its presence in space. The Shenzou-14 mission is the third crewed journey to the station. Earlier, three astronauts also spent six months there, including Wang Yaping, the first Chinese woman to perform a spacewalk. The latest crew will complete the assembly and construction of Tiangong, expanding it from a single-module structure to a three-module national space laboratory. This will comprise the Tianhe core module and two laboratory modules, Wentian and Mengtian. "We have already entered the core module, and the Wentian and Mengtian laboratory modules will arrive soon,” Ms Yang told Chinese news agency CCTV+. “By then, we will have completed the construction of our own space station, our home in space." Two cargo spacecrafts, <i>Tianzhou-3</i> and <i>Tianzhou-4</i>, were launched earlier on and docked with the station. During the crew’s first week on Tiangong, their job will be to enter the cargo spacecraft and transfer the supplies. Liu Weibo, research associate at the China Astronaut Research and Training Centre, said they will create a “normal working environment” after their arrival. “They will have to take out daily necessities from the cargo ship, including food and water, as well as other consumables necessary to ensure a normal working environment, such as ventilation equipment and air filters,” he told CCTV+. “These will need to be taken out of the cargo spacecraft and installed in their corresponding positions in the Tianhe core module, so that, the cargo spacecraft, Tianhe core module and Shenzhou spacecraft will be fully connected, forming a complex under comprehensive control." The crew will be carrying out 24 science experiments during their stay on Tiangong, including ones that will study the impact of weightlessness on the human body. Li Yinghui, deputy chief designer of the astronaut system, said the experiments will also focus on space medicinal science. "We've also added in-orbit collection of body fluids, including blood, urine and saliva, which is important to space medicinal science,” he said. “The non-invasive optical measurement of muscle could be an important way to evaluate muscular atrophy. “We can use the analysis of metabolites in urine directly in the evaluation of astronauts' health. These analytical techniques and methods can serve our health care.” China has ambitions to become a leading space power, with a thriving sector that includes human flights to its new space station in low-Earth orbit, planetary, lunar and deep-space exploration, a satellite navigation system and the continued development of its space transport system. China’s space agency released white papers earlier this year that revealed the country’s space ambitions and progress made so far. From 2016 to December 2021, the country completed 207 launch missions, including 183 by the Long March carrier rocket series. China has already landed a spacecraft on the Moon and Mars. In the next five years, China will integrate space science, technology and applications while pursuing the new development philosophy, building a new development model and meeting the requirements for high-quality development,” it said in the papers. “It will start a new journey towards a space power. “The space industry will contribute more to China's growth as a whole, to global consensus and common effort with regard to outer space exploration and utilisation, and to human progress.”