Can debris of fallen Tiangong-1 space lab reveal secrets of China’s space programme?
In the wake of the crash, a scientist has revealed that Beijing routinely reclaims its fallen space debris to keep sensitive information secret - even when it lands in another country
China will not deploy a team to salvage debris from Tiangong-1, its experimental space laboratory that returned to Earth on Monday, local scientists said amid speculation that the remains might provide some insight into the state of the country’s space programme.
“We only retrieve assets of high value, or those that contain sensitive technology or intelligence that would cause harm if falling into the hands of another country,” a space scientist familiar with the operation told the South China Morning Post on condition of anonymity.
Tiangong-1 was not such an asset, he said.
The eight-tonne space lab, which measured about the size of a school bus, crashed into the southern Pacific Ocean about 8.15am Hong Kong time (00.15 GMT), ending weeks of uncertainty as to where it would end up.
Almost all of its components disintegrated during re-entry into the Earth’s atmosphere, Chinese space authorities said.
Whatever survived was most likely scattered across a large area, while heavier materials would have sunk to the seabed, thousands of metres below, they said.
The scientist said that some lightweight structures might drift on the current and wash up on a distant shore sometime in the future, though confirming they had come from Tiangong rather than another spacecraft would be technically challenging.
Under the right conditions, scientists can gather sensitive information from spacecraft debris, such as what materials were used in its construction, which would point to a country’s progress on space research.
However, according to international space law, all such debris belongs to the country of origin, regardless where it falls.
While Beijing had decided there was little value in deploying a team to salvage the remains of Tiangong-1, there had been occasions when it was deemed necessary, the scientist said.
A secret team with close ties to the military had previously been used to retrieve debris from Chinese satellites that had fallen to Earth in foreign lands, he said.
Several years, ago, a satellite that contained sensitive military technology crashed in the Australian Outback soon after its launch aboard a Long March rocket.
“Our men went in and came out quietly,” he said. “They returned with the asset in one piece.”
He declined to provide any further details about the retrieval mission, including wether Australian authorities were even aware of it, but said it had never been publicly reported.
Zhu Jin, director of Beijing Planetarium, said it made no sense for China to send a ship to salvage the remains of Tiangong-1.
“It’s not like there were crew on-board who needed to be rescued,” he said. “There is nothing valuable, just a piece of junk.”
Tiangong-1, which translates as “Heavenly Palace 1”, was launched into orbit on September 29, 2011, and was used to carry out docking and orbit experiments as part of China’s ambitious space programme, which aims to build a permanent station by the early 2020s. In its time it successfully docked with the Shenzhou-8, Shenzhou-9 and Shenzhou-10 spacecrafts.
The module terminated its data service on March 16, 2016, marking the end of its mission and start of its orbital decay, although until late last month, Chinese authorities denied it was out of control as it hurtled home.
Tiangong’s re-entry into the Earth’s atmosphere happened somewhere north of Point Nemo, a location named in honour of Jules Verne’s fictional submarine captain and which is also Latin for “no one”.
The spot, which is a graveyard for more than 200 spacecraft, is one of the most remote on the planet and is officially known as an “oceanic pole of inaccessibility”.
Controlled re-entries of spacecraft have often been directed to Point Nemo because of its remote location and lack of biodiversity, according to Stijn Lemmens, a space debris expert at the European Space Agency in Darmstadt, Germany.
By far the largest object to have splashed down there was Russia’s MIR space lab in 2001, which weighed in at 120 tonnes before it broke up on re-entry. The massive 420-tonne International Space Station is also expected to crash down at Point Nemo in 2024.
Additional reporting by Agence France-Presse