Stars reveal carbon 'spaceballs'
By Victoria Gill
22 July 2010
Science reporter, BBC News
The football-shaped molecules are the largest molecules ever found in space足球狀的分子，是迄今在太空發現的最大分子
Scientists have detected the largest molecules ever seen in space, in a cloud of cosmic dust surrounding a distant star.
科學家已探測到太空有史以來最大的分子，在圍繞一顆遙遠恆星的宇宙塵埃雲中。
The football-shaped carbon molecules are known as buckyballs, and were only discovered on Earth 25 years ago when they were made in a laboratory.
足球狀的碳分子被稱為布基球，並只在25年前發現在地球上，當它們被製成於實驗室中。
These molecules are the "third type of carbon" - with the first two types being graphite and diamond.
這些分子是“碳的第三類型” - 前兩類型是石墨和鑽石。
The researchers report their findings in the journal Science.
研究人員報告他們的發現在科學雜誌上。
They belong to a class of molecules called buckministerfullerenes - named after the architect Richard Buckminister Fuller, who developed the geodesic dome design that they so closely resemble.
它們屬於一類分子稱為 buckministerfullerenes - 命名在建築師理查德巴克敏斯特富勒之後，它發展測地線拱頂的設計，他們是如此密切地相似。
The research group, led by Jan Cami from the University of Western Ontario in Canada, made its discovery using Nasa's Spitzer infrared telescope.
研究小組由加拿大西安大略大學的揚卡米領導，發現是使用美國宇航局的斯皮策紅外望遠鏡。
Professor Cami and his colleagues were not specifically looking for buckyballs, but spotted their unmistakable infrared "signature".
"They oscillate and vibrate in lots of different ways, and in doing so they interact with infrared light at very specific wavelengths," explained Professor Cami.
When the telescope detected emissions at those wavelengths, Professor Cami knew he was looking a signal from the largest molecules ever found in space.
"Some of my undergraduate students call me a world record holder," he told BBC News. "But I don't think there's a record for that."
The molecules were named after the developer of the geodesic dome分子被命名在測地線圓頂的發展者之後
The signal came from a star in the southern hemisphere constellation of Ara, 6,500 light-years away.
信號來自一南半球星座天壇星座的恆星，距離6,500光年。
Professor Cami said the discovery was perhaps not surprising, but was "very exciting".
"Lots of scientists have expected that they would exist in space, because they are amongst the most stable and durable of materials," he said.
"So once they've formed in space, would be very hard to destroy them.
"But this is clear evidence of an entirely new class of molecule existing there."
The researchers now want to find out what fraction of the Universe's carbon might be "locked up" in these spheres.
They also want to use the known properties of buckyballs to gain a better understanding of physical and chemical processes in space.
The discovery may even help shed light on other unexplained chemical signatures that have already been detected in cosmic dust.
Third way
Back on Earth, the discovery of buckyballs' existence was also accidental. Researchers were attempting to simulate conditions in the atmospheres of ageing, carbon-rich giant stars, in which chains of carbon had been detected.
"The experiments were set up to make those long carbon chains, and then something unexpected came out - these soccer ball type molecules, which just looked weird," said Professor Cami.
"And now it turns out that those conditions that were deliberately created in a laboratory actually occur in space too - we just had to look in the right place."
Sir Harry Kroto, now at Florida State University in the US, shared the 1996 Nobel Prize in Chemistry for the discovery of buckyballs.
He commented: "This most exciting breakthrough provides convincing evidence that the buckyball has, as I long suspected, existed since time immemorial in the dark recesses of our galaxy.
"I think of the buckyball as being like Orson Welles' mysterious character in The Third Man, revealing itself only fleetingly."
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