The Canadian Space Operations Centre (CANSpOC) is the Royal Canadian Air Force’s Director General Space’s operational unit; it provides space domain awareness and surveillance to the Canadian Armed Forces as well as other governmental and commercial entities. The data it collects and analyzes is used to support domestic, deployed military and civil operations on a global scale.
The CANSpOC recently tracked the Chinese space station called Tiangong-1 (which translates as “Heavenly Palace”). The station, launched in 2011, was China’s first space station. It was home to Chinese astronauts on two occasions but had been unmanned since the summer of 2013. China lost control of the station in 2016 and its orbit began to slowly decay. It burned up on re-entry and broke apart on Sunday, April 1, 2018, over the southern Pacific Ocean.
Tiangong-1 orbited between 42.75°N and 42.75°S, meaning that it was certain the station would only re-enter between these latitudes. This constitutes about two-thirds of the Earth’s entire surface, half of which is covered by water. Canada covers an area from 41.65°S to 83.10°N latitudes. Consequently, the only region within Canada that could have been potentially at risk of falling space debris was the very southern tip of Ontario.
The station’s shape, size and material determined whether it would have completely burned up in the atmosphere or broken up into smaller pieces that could have survived re-entry. Tiangong-1’s considerable mass of approximatively 8,500 kilograms created concerns that pieces of debris might survive re-entry.
The CANSpOC collaborated with military counterparts from Australia, France, Germany, the United Kingdom and the United States to perform a series of predictions of Tiangong-1’s final re-entry point. Predicting the location where a space object will re-enter is a complex task due to the fluctuation of many variables such as the orientation of the object and atmospheric density. As the re-entry date approached, the uncertainty shrank and the predictions became more accurate. The CANSpOC provided warnings and updates to the appropriate entities in Government of Canada such as Public Safety until the space station broke up while entering earth’s atmosphere.