China icebreaker fails to reach stuck Antarctic ship
A scientific mission ship, trapped in dense pack ice off East Antarctica, is still awaiting rescue after a Chinese icebreaker failed to reach it.
The Snow Dragon icebreaker was itself stalled by heavy ice, officials say.
It had been trying to cut a path through the ice in order to help the research vessel reach open water.
The Russian Academician Shokalskiy, trapped since Christmas Day, has 74 people on board and is being used by the Australasian Antarctic Expedition.
They are following the route explorer Douglas Mawson travelled a century ago.
One of the leaders of the expedition, Chris Turney, earlier tweeted an image of the Snow Dragon icebreaker - also known as the Xue Long - on the horizon as it approached the research ship.
The Chinese vessel came within seven nautical miles (11 km) of the expedition ship, but encountered heavy ice and was forced to return to the open sea.
"Our rescue boat, the Xue Long, has had to turn back because the ice was too thick for it to get through," said Alok Jha, a journalist on board the Shokalskiy.
The Australian Maritime Safety Authority, which is coordinating the rescue, confirmed that a French vessel had also failed to penetrate the ice.
The agency said another boat, the Aurora Australis, was on its way to the Russian vessel and expected to arrive on Sunday.
"I think we're probably looking at another 24 hours of twiddling our fingers and waiting for something to happen," expedition spokesman Alvin Stone told the Associated Press.
Correspondents say expedition members could be winched to safety by a helicopter if the weather remains favourable.
The research ship 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.
There had also been fears that blizzards could hamper the rescue effort.
The Shokalskiy is well stocked with food and is in no danger, according to the team.
Although trapped for the moment, the scientists are continuing their experiments. They have been measuring temperature and salinity through cracks in the surrounding ice.
Science volunteer Sean Borkovic told the BBC: "I'll always remember this, that's for sure. It's brilliant. We've got some lovely light and the weather's pretty mild considering. The ship looks solid. I think we'll be good."
A visit from Secret Santa and a sumptuous Christmas dinner contributed to the mood of optimism.
The goal of the modern day Australasian Antarctic Expedition is to repeat many of the original measurements and studies of the Mawson expedition to see how facets of the environment have changed over the past century.