Tiangong-1 space laboratory to crash to Earth within months
Artist’s rendition of Tiangong-1 in Earth orbit. Image Credit: CMSA
It could be just a matter of few weeks or months before China’s Tiangong-1 space laboratory will fall to Earth. The spacecraft is continuing its gradual descent toward the surface after control over the mission was lost in early 2016.
Tiangong-1 (“Heavenly Palace” in Chinese) is China’s first space laboratory. With a mass of 8.5 metric tons, it measures some 34 feet (10.4 meters) long and has a diameter of 11 feet (3.4 meters).
The laboratory was launched on September 29, 2011. Nine months later, in June 2012, three Chinese taikonauts docked their Shenzhou-9 spacecraft to the station for the first time. The module was visited again in June 2013 when the Shenzhou-10 spacecraft transported another trio of taikonauts.
Besides being used as a laboratory for research in space, Tiangong-1 also served as an experimental module to demonstrate orbital rendezvous and docking capabilities. The laboratory paved the way for China’s future space station, which the country plans to complete in 2022. Along with its predecessor, Tiangong-2 (launched in September 2016), it tested technologies crucial for the planned modular orbital outpost.
Although Tiangong-1 was initially scheduled to be deorbited in 2013, it still orbits the Earth unoccupied after the Shenzhou-10 crew left the station in June 2013. The laboratory was then put into sleep mode, which allowed mission controllers to collect data on the longevity of its key components.
Problems with Tiangong-1 started on March 16, 2016, when it ceased functioning, most likely due to a dysfunctional battery charger. Since then, the module has been unable to recharge its batteries from its two solar arrays. However, five days later, the China Manned Space Engineering Office (CSME) only informed the public that the spacecraft started to descend gradually and would eventually fall back to Earth.
The imminent crash to our planet was finally confirmed by Chinese officials half a year later when Wu Ping, the deputy director of CSME, revealed that the laboratory is intact and orbiting at an average altitude of 230 miles (370 kilometers). She added that the descent will end in the spacecraft’s burn-up in the atmosphere in late 2017, most likely without any damage to the ground.
However, some experts raised worries that some of Tiangong-1’s parts, especially the rocket engines, will not burn up completely and could cause minor damages on the ground.
“There will be lumps of about 100 kilograms [220 pounds] or so, still enough to give you a nasty wallop if it hit you,” Jonathan McDowell, Harvard astrophysicist and space industry enthusiast, told The Guardian in September 2016.
In May 2017, China informed the United Nations (UN) that Tiangong-1 is at an altitude of 217 miles (349 kilometers) and its orbit is decaying at a daily rate of approximately 525 feet (160 meters). According to new estimates, the re-entry of the spacecraft is expected sometime between October 2017 and April 2018.
In a note to the UN Secretary-General, China insists that most parts of Tiangong-1 will be destroyed during re-entry. According to Beijing, there is very low probability that the pieces surviving atmospheric burnout could endanger aviation and ground activities.
Moreover, China assured the UN that it is committed to further monitoring and forecasting the descent of Tiangong-1. The country will inform the public as soon as more information is available, mainly regarding the time and region of re-entry.
Tomasz Nowakowski
Tomasz Nowakowski is the owner of Astro Watch, one of the premier astronomy and science-related blogs on the internet. Nowakowski reached out to SpaceFlight Insider in an effort to have the two space-related websites collaborate. Nowakowski's generous offer was gratefully received with the two organizations now working to better relay important developments as they pertain to space exploration.
I’m just surprised that no experimental space debris removal system has been offered to the Chinese government. Ultimately, this needless scenario was created by China’s human spaceflight program which did not deorbit Tiangong-1 when it had ample opportunity to do so.