Astronauts aboard the Tiangong-1 space lab. Credit: Xinhua
Earlier this month, headlines claimed that China’s space station, Tiangong-1, was uncontrollably “hurtling towards Earth.” Indeed the Tiangong-1 is hurtling toward Earth—that’s what things in orbit do for a living. Less accurate, perhaps, is the headline’s use of the term “space station.”
Despite recent stories, China's Tiangong-1 spacelab is not about to reenter. Let's see if it reboosts or not by 2017 pic.twitter.com/VcF93MLgHT
— Jonathan McDowell (@planet4589) July 12, 2016
The image of something like the International Space Station crashing into your backyard would indeed be terrifying, but it’s important to note that the Tiangong-1 is much more akin to a large satellite—the sort of object that falls back through Earth’s atmosphere fairly frequently.
Tiangong-1 was launched in 2011 as the first step in a long process China has planned to make an ISS-like station of their own, an effort codenamed Project 921-2. The Tiangong-1 was the first object launched into space as part of this program, and it was actually expected to fall back to Earth back in 2013.
Panic about its fall to Earth was inspired by an announcement that China had lost telemetry data from the craft, leading some media outlets to publish speculation that it would undergo an uncontrolled descent—something that is, at least, a possibility. However, China’s state-run news agency announced that they expect it burn up in the atmosphere as its orbit decays in the coming months, and states that the craft is “under continued and close monitoring.”
What did Tiangong-1 contribute to the effort to build a Chinese Space Station and what else will China be doing before they move on to the final project? Here are the bullet points:
A drawing of the future space station provided by the China Manned Space Engineering program. Credit: CMSE.
Early Steps: The Tiangong-1
The goals of the Tiangong-1 program (Tiangong translates as ‘heavenly palace’) were focused on testing the system’s autonomous and manual docking systems, something accomplished over three missions—one uncrewed, and two crewed missions (which included a flight by Liu Yang, China’s first female astronaut).
Over the course of these missions, spacecraft automatically (and also manually, as part of testing) docked and maintained cabin pressure between the Tiangong and the crafts. In addition to this primary objective, Chinese astronauts conducted a number of medical experiments as well. Perhaps the most notable event was part of the final mission to the Tiangong-1, which included a live science lecture in which astronauts performed a number of basic experiments for millions of Chinese students to watch live:
An Upcoming Launch: Tiangong-2
Tiangong-2, the next phase of project 921-2, is expected to launch in September of this year. This craft is slightly bigger than its predecessor and aims to enable two astronauts to live in space for up to 30 days. China National Space Administration (CNSA) expects there to be two missions to this space lab—one unmanned resupply mission, and one crewed mission.
According to an official government statement, Tiangong-2 “will be a testing place for systems and processes for mid-term space stays and refueling in space,” and will “also be involved in experiments on aerospace medicine, space sciences, on-orbit maintenance and space station technologies.” On the outreach side of things, three student experiments—winners of a national contest—will be conducted the Tiangong-2 as well.
Screenshot released by China’s Xinhua News Agency of the Shenzhou-9 spacecraft and Tiangong-1 lab module. Credit: AP Photo/Beijing Aerospace Control Center via Xinhua.
The Beginning Of A Modern Station: Tianhe-1
When Project 921-2 began, the plan was to have a third test vehicle, the Tiangong-3, launched prior to the construction of the actual station. However, in April of this year, China said that they have no need for this mission to run as a test, and instead, it will form the first module of the space station itself.
Model of the Tiangong-1 docked to a the Shenzhou-10. Credit: Xinhua
It was always the intention for the Tiangong designs to be repurposed for the final space station. For the final space station. This specific adjustment was made possible, China said, by their ability to include all the necessary tests on the Tiangong-2 mission, cutting back on both cost and time. The new mission, Tianhe-1, aims to launch a module that will be the “core capsule” (sort of the centerpiece around which everything is built) of their new space station by around 2018. The plan for the rest of the station is to add two laboratory units, each modeled off of the Tiangong-2, joined to the core capsule. A fourth module, based off of the Tiangong-1, will serve as a transport vessel to the station.
China has high hopes for this station. Wang Zhongyan, a spokesperson for the research group associated with the space station project, noted that if the International Space Station is retired in 2024 as planned, their station would be the only operational one in space, positioning China to be a much bigger player in the international space game.