Antarctic rescue of Akademik Shokalskiy ship completed
Rescuers in Antarctica have safely transferred all 52 passengers stranded on the ice-bound research vessel Akademik Shokalskiy.
The Australian rescue operators said the scientists and tourists were now all aboard the ship Aurora Australis.
They were flown there in groups by a helicopter from a Chinese ice-breaker.
The Shokalskiy has been trapped since 24 December. Its 22 crew are expected to remain on board to wait until the vessel becomes free.
The Shokalskiy was trapped by thick sheets of ice driven by strong winds, about 1,500 nautical miles south of Hobart - the capital of the Australian state of Tasmania.
The vessel was being used by the Australasian Antarctic Expedition to follow the route explorer Douglas Mawson travelled a century ago.'White-knuckle ride'
"We've made it to the Aurora australis safe & sound. A huge thanks to the Chinese & @AusAntarctic for all their hard work!," expedition leader Chris Turney tweeted.
The helicopter belongs to the Chinese icebreaker, Xue Long, and each flight took about 45 minutes, round-trip.
The BBC's Andrew Luck-Baker, who was on board the Akademik Shokalskiy, says the 15-minute one-way flight was a "white-knuckle ride".
The passengers were taken to an ice floe next to the Aurora Australis and then ferried on to the ice-breaker by a small boat.
Our correspondent says the Russian crew staying behind could be on the Akademik Shokalskiy for weeks before the pack ice clears.
The Return to Mawson's Antarctica
- The 2013 Australasian Antarctic Expedition repeats scientific investigations made by Douglas Mawson and his team between 1911 and 1914
- Andrew Luck-Baker and Alok Jha are reporting on the expedition for Discovery on the BBC World Service
- Listen to Part One, Part Two and Part Three of their story, or get the Discovery podcast
The Australian Maritime Safety Authority's (Amsa) Rescue Co-ordination Centre, which was overseeing the operation, had earlier said it was unlikely the rescue would go ahead on Thursday as hoped because of the sea-ice conditions.
But it later reported: "Aurora Australis has advised Amsa that the 52 passengers from the Akademik Shokalskiy are now on board."
The passengers are not expected back in Tasmania until mid-January.
Several attempts to break through to the ship by sea - by the Xue Long, Aurora Australis and French-flagged L'Astrolabe - failed because of the thickness of the ice.
Andrew Luck-Baker says the Aurora Australis, although big, was simply not up to the task and there is speculation two larger vessels may be coming to the area in the weeks to come.
Despite being trapped, the scientists continued their experiments, measuring temperature and salinity through cracks in the surrounding ice.
One of the aims was to track how quickly the Antarctic's sea ice was disappearing.
The ship had plenty of stocks and was never in danger.