Friday, July 19, in China Tiangong-2 The space laboratory ("Celestial Palace") successfully entered the Earth's atmosphere under controlled conditions and burned over the South Pacific Ocean. This marked the successful conclusion of all the tasks of Tiangong-2, which constituted China's second attempt to prove its ability to carry out human investigations and operations in low Earth orbit (LEO).
According to China's manned space agency, Tiangong-2 entered the atmosphere at 9:06 PM in Beijing (06:06 AM PDT; 09:06 AM EDT). While some waste fell into a "predetermined safe marine area in the South Pacific," most of the space laboratory burned during the descent. In total, the station spent more than 1,000 days in orbit, considerably exceeding its useful life of two years and orbiting the Earth 16,209 times.
Tiangong-2 It was launched in orbit on September 15, 2016 and since then it has achieved impressive feats. These include completing four successive couplings with the Shenzhou-11 manned spacecraft and he Tianzhou-1 cargo spacecraft. During its many orbits on Earth, Tiangong-2 He supported teams of two astronauts who would reside and work at the station for a period of 30 days.
The station also allowed for a series of key technological advances and completed a series of extended tests during its service. These successes and those of their predecessor – Tiangong-1 – Establish the bases for the development, construction, deployment and operations on board the third and last orbital laboratory of China, the large modular space station (LMSS).
Astronaut Jing Haipeng said that he spent his 50th anniversary in Tiangong-2 on October 24, 2016:
"As the first to enter Tiangong-2, I am pleased that the space laboratory has successfully completed its tasks, although I also do it because it was our home in the space. My memory of the 30 days Tiangong-2 with Chen Dong is still fresh. We have done many scientific experiments, such as raising silkworms and growing plants in space. China intensifies efforts to prepare for the construction of the station Space. We are sure that a space station belonging to the Chinese people will arrive soon. "
"The 30 days of Tiangong-2 were the happiest and most unforgettable experience of me
Unfortunately, it was time that the second "Celestial Palace" returned to Earth before it stopped working and it became an abandoned space station. Zhu Zongpeng of the Chinese Academy of Space Technology was the chief designer of Tiangong-2. As explained in a recent interview with Xinhua:
"It's hard to say goodbye to Tiangong-2, but keeping in mind the factors related to reliability and security, we have to leave it out of the way. Allowing Tiangong-2" to withdraw "by decision is to guarantee the absolute security of its exit,
This decision was probably reported for the re-entry of the Tiangong-1 space station to April 2018, which took place two years after it had stopped working. In comparison, this event had been somewhat an uncontrolled affair. Initially, the authorities were worried because it was not entirely clear if the Chinese were still in control of the station.
As the descent approached, there were other concerns about the date of the re-entry of the station, where it would fall and what remains could survive, which were subject to some conjectures. However, Tiangong-1 and his successor have now been returned to Earth safely and the lessons learned from these will be useful when the LMSS is operational.
The first module (the Core Cabin) is expected to be placed in orbit next year, while the other two (the Wentian and the Mengtian Laboratory) will be launched in 2021 and 2022, respectively. Along with three coupling ports, an EVA hatch and multiple solar panels, China intends to assemble the entire space station in 2022.
Since the international space station (ISS) will be retired in 2024, this means that China will be the only nation with a space station in orbit at that time. However, the LMSS will be much smaller, measuring approximately the same size as those of the current retirement of Russia Mir Space station. It will also have about a fifth of the mass of the ISS, which weighs around 400 metric tons (441 tons of the United States).
All this serves to highlight the achievements of the Chinese space program, which has followed a "three step development" strategy for the last 20 years. At this time, China has sent 11 manned spacecraft, two space labs and has sent 14 astronauts to the space and has taken them home safely.
In the coming years and decades, China will send many more robotic missions to the space and even wait for missions to the Moon. It is also expected that China will join space agencies such as NASA, Roscosmos, ESA of ISRO for projects such as the International Moon Village and other large space companies.
Read more: phys.org, Xinhua, CMSA