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Space

Tiangong-1’s watery grave in the remotest place on Earth

Fragments of China’s orbiting laboratory that survived re-entry through the atmosphere have fallen into an ‘oceanic pole of inaccessibility’ which contains other space debris

PUBLISHED : Monday, 02 April, 2018, 3:06pm
UPDATED : Monday, 02 April, 2018, 5:28pm

Chinese space scientists were not in control of the Tiangong-1 orbiting laboratory when it hurtled back to Earth, burning up in the atmosphere and falling into a remote part of the Pacific Ocean on Monday. But if they had been, that is where they would have tried to make it land.

By sheer fluke, anything that did not burn up is expected to have fallen somewhere near the forlorn spot that is among the most remote places on the planet.

Officially called an “oceanic pole of inaccessibility”, this watery graveyard for hi-tech space debris is better known to space junkies as Point Nemo, in honour of Jules Verne’s fictional submarine captain.

“Nemo” is also Latin for “no one”.

China’s Tiangong-1 space lab finally returns to Earth, burning up over South Pacific

Point Nemo is further from land than any other dot on the globe, 2,688km (about 1,450 miles) from the Pitcairn Islands to the north, one of the Easter Islands to the northwest and Maher Island, part of Antarctica, to the South.

“Its most attractive feature for controlled re-entries is that nobody is living there,” said Stijn Lemmens, a space debris expert at the European Space Agency in Darmstadt, Germany.

“Coincidentally, it is also biologically not very diverse. So it gets used as a dumping ground – ‘space graveyard’ would be a more polite term – mainly for cargo spacecraft,” he said.

Some 250 to 300 spacecraft – which have mostly burned up as they carved a path through Earth’s atmosphere – have been laid to rest there, he said.

By far the largest object descending from the heavens to splash down at Point Nemo, in 2001, was Russia’s MIR space lab, which weighed 120 tonnes before it broke up on re-entry.

The massive, 420-tonne International Space Station also has a rendezvous with destiny at Point Nemo, in 2024.

In future, most spacecraft will be “designed for demise” with materials that melt at lower temperatures, making them far less likely to survive re-entry and hit the Earth’s surface.

Both Nasa and the European Space Agency, for example, are switching from titanium to aluminium in the manufacture of fuel tanks.

China hoisted Tiangong-1, its first manned space lab, into space in 2011. It was slated for a controlled re-entry, but ground engineers lost control of the eight-tonne craft in March 2016, which is when it began its descent towards a fiery end.

What the Tiangong-1 space station meant for China’s ambitions

The lab’s demise has been the subject of much chatter among space watchers for months, with the uncertainty of its atmospheric re-entry attracting much attention over recent days.

Scientists had only been able to give the most general of forecasts for exactly when and where the lab would plunge back to Earth, offering a huge band of the planet that included almost all of South America, Africa and Asia, as well as the southern portions of the Atlantic and the Pacific Oceans.

Despite the vagueness of their forecasts, scientists said there was an infinitesimally small chance that anybody would be hurt by the remnants of the lab and that it would most probably land in the ocean.