Rare things happen once in a blue moon, and on New Year's Day a blue moon, coupled with an exceptionally low tide, uncovered a long-sought treasure in the frozen wastes of Antarctica: one of the world's earliest aeroplanes, entombed in ice for decades.
The plane – the first off the Vickers production line in Britain – was built in 1911, only eight years after the Wright brothers executed the first powered flight. It was taken to Antarctica by Douglas Mawson, the Australian explorer, but abandoned in 1914 after its engine seized up during attempts to use it as an "air tractor", or motorised sledge.
For the past three years, a team of Australian explorers has been engaged in a fruitless search for the aircraft, last seen in 1975. Then on Friday, a carpenter with the team, Mark Farrell, struck gold: wandering along the icy shore near the team's camp, he noticed large fragments of metal sitting among the rocks, just a few inches beneath the water.
Tony Stewart, the field leader, said: "The carpenter just ambled in and said, 'I think I might have found the air tractor,' like he'd just picked up a newspaper at the local store. You haven't seen us move so quickly in a long time."
It was part of the fuselage of the historic plane, exposed by a blue moon (the second full moon in a calendar month), the lowest tide ever recorded at that site and an unprecedented melting of ice. "It was probably one chance in a million that these conditions just allowed us to spot it," said David Jensen, the chairman of the Mawson's Huts Foundation, the Australian government-backed organisation that led the search.
Mawson had hoped to stage the first flight over the Antarctic ice cap, but the plane crashed on the Australian mainland before he set sail. No one was hurt, but with the wings damaged and no time to repair them, the explorer adapted the craft to haul his sledges, adding skis to the undercarriage and a special tail-rudder.
After the Vickers' engine failed in sub-zero temperatures, Mawson dumped it at Cape Denison, at the head of Commonwealth Bay. It was still sitting on the ice when he returned in 1929 and 1931, and in 1975 it was photographed after a big ice melt. But without the "fluke" conditions on New Year's Day, it could have disappeared without trace, said Mr Jensen.
"The tide would have come in and we would never have seen it again," he said. "It's a remarkable find in remarkable circumstances." Mr Jensen said the plane, rediscovered almost a century after being abandoned, was "part of aviation history".
Having used magnetic imaging equipment to search for it, conservationists were getting ready to drill into the ice in conditions including 50mph winds and below-freezing temperatures. "Luck was on our side, without a doubt," Dr Stewart said.
Considered one of the great polar explorers, Mawson, from Yorkshire, joined the Nimrod Expedition led by Ernest Shackleton in 1907, and was later a member of the first team to reach the South Magnetic Pole.
He led an expedition to Antarctica from 1911-14, during which a member of his three-man team fell into a massive crevasse, along with six dogs and most of the food and supplies. The other two men were forced to eat some of the surviving dogs. Mawson's companion died after suffering frostbite and seizures, and he completed the final 100 miles back to base alone.
The plane, the first to be taken to a polar region, was crashed by its hungover pilot during a test flight over Australia. He was sent home to Britain in disgrace. Now the Australian Antarctic Division is deciding whether to repatriate the Vickers for specialist conservation work, or leave it at Cape Denison.
Mawson removed the aircraft's wings before transporting it to Antarctica, and its engine was later sent back to Vickers. But pieces of the fuselage were left behind.