Tiangong-1: What Did Uncontrolled Space Station Heading for Earth Actually Do?

You may have heard that an uncontrolled space station is set to collide with Earth in the next few days. China's Tiangong-1 space station, launched back in 2011, is set to re-enter Earth's atmosphere soon in an almost-definitely safe and potentially spectacular blaze.

The space laboratory was sent into orbit around Earth as part of China's Tiangong ("Heavenly Palace") program, which should eventually send up a much larger modular station.

Originally set to deorbit in 2013, Tiangong-1's lifespan was extended by two years before its comms went silent. While operational, however, the lab sent back a host of valuable data, investigating Earth itself and the atmosphere above. Below, its most important contributions.

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The Long March II-F rocket is seen launching with Tiangong-1 in tow at the Jiuquan Satellite Launch Center in China on September 29, 2011. Petar Kujundzic/Reuters

Detailed Earth Observations

Earth observation was one of Tiangong-1's main functions. Its hyperspectral imager collected data from across the electromagnetic spectrum, producing highly accurate pictures of towns and cities below with a much finer spatial resolution than older satellites.

Tiangong-1's data, China's Manned Space Engineering office reported, could be used for mineral resource investigation, hydrological and ecological environmental monitoring, urban thermal environment monitoring, land use and emergency disaster control.

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A graphic representation of hyperspectral data, not sourced Tiangong-1. Tiangong-1 was capable of providing a finer spatial resolution than older systems. Nicholas M Short Sr/NASA/Public Domain

In fact, the CSME credited the space lab with providing "timely hyperspectral observation data" during natural disasters including floods in the eastern Chinese city of Yuyao and wildfires in Australia in 2013.

Probing the Ionosphere

As well as keeping an eye on Earth itself, Tiangong-1 was equipped with devices to probe the boundary of Earth's atmosphere and space, the ionosphere, the Earth Observation Portal reports. Particles in this upper bracket of the atmosphere are charged by the radiation from the sun.

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Tiangong-1's instruments, eoPortal reports, could detect and analyze these charged particles, and measure disturbances in the ionosphere.

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NASA's GOLD instrument is designed to scan the whole of the Earth’s disk every half hour. NASA

Hard-to-measure changes in this part of the atmosphere can affect our daily life on Earth, messing up cell phones and GPS systems. NASA is so concerned about the combination of space weather, Earth weather and our planet's magnetic field in this region that it sent the sophisticated GOLD satellite to study it earlier this year.

As well as tools to probe the atmosphere, Tiangong-1 carried the ingredients for crystal growth experiments—images and videos of which could be beamed to Earth.

Engineering Accomplishments

As well as scientific experiments, Tiangong-1 was key for China's modular space station ambitions. It saw the docking of three Shenzhou spacecraft from 2011 to 2013.

The November 2011 Shenzhou 8 mission saw its spacecraft dock twice with the orbiting lab. The unmanned craft docked Tiangong-1 automatically.

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In June 2012, China sent its Shenzhou 9 mission to Tiangong-1, carrying a Chinese woman into space for the first time. Liu Yang accompanied crew members Jing Haipeng and Liu Wang. Their spacecraft docked with the space lab twice—once via ground-based remote control and once manually.

Liu Yang was tasked with improving crew workflow and performing medical experiments alongside her other astronaut duties, according to an Asian Scientist profile.

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A girl asks astronaut Wang Yaping questions during a lesson given from Tiangong-1 on June 20, 2013. STR/AFP/Getty Images

Less than a year later, China sent its second and last manned mission to Tiangong-1. The Shenzhou 10 crew docked just once and stayed fastened to the space station for 12 days.

The mission famously saw an in-space science lesson. Astronaut Wang Yaping gave a physics class from space, teaching some 60 million Chinese students about the behavior of pendulums, gyros and water in space.

After Tiangong-1, China's space station torch passed to Tiangong-2. Launched in 2016, this lab is designed to serve as a testing ground for tech that will be used on the Chinese large modular space station. Its main core module, Tianhe-1, is reportedly due to launch in 2019.