科學家在“外星”彗星內(nèi)部發(fā)現(xiàn)了奇怪的化學成分

科學家在“外星”彗星內(nèi)部發(fā)現(xiàn)了奇怪的化學成分

Scientists have discovered that a comet called 2I/Borisov – only the second interstellar object ever detected passing through the solar system – is surprisingly different in its composition from comets hailing from our celestial neighborhood.

科學家們發(fā)現(xiàn)，一顆名為2I/Borisov的彗星——這是迄今為止發(fā)現(xiàn)的第二顆穿越太陽系的星際物體——其組成與來自我們的天體鄰居的彗星驚人地不同。

Gas coming off 2I/Borisov contained high amounts of carbon monoxide – far more than comets formed in our solar system – indicating the object had large concentrations of carbon monoxide ice, researchers said on Monday.

研究人員于本周一稱，2I/Borisov彗星釋放出的氣體中含有大量的一氧化碳——遠遠多于太陽系中形成的彗星——這表明該物體中含有大量的一氧化碳冰。

Carbon monoxide, poisonous to humans, is common as a gas in space and forms as ice only in the most frigid locations. The presence of so much carbon monoxide, the researchers said, suggests 2I/Borisov formed in a different manner than comets in our solar system – in a very cold outer region of its home star system or around a star cooler than the sun.

對人類有毒的一氧化碳在太空中以氣體的形式存在，只有在最寒冷的地方才會形成冰。研究人員說，這么多一氧化碳的存在表明，2I/Borisov彗星的形成方式與我們太陽系中的彗星不同——其母星系統(tǒng)的一個非常寒冷的外部區(qū)域，或者在一個比太陽還要冷的恒星周圍。

Comets essentially are dirty snowballs composed of frozen gases, rock and dust that orbit stars.

彗星本質(zhì)上是由圍繞恒星運行的冰凍氣體、巖石和塵埃組成的臟雪球。

“We like to refer to 2I/Borisov as a snowman from a dark and cold place,” said planetary scientist Dennis Bodewits of Auburn University in Alabama, lead author of one of two 2I/Borisov studies published in the journal Nature Astronomy.

阿拉巴馬州奧本大學的行星科學家Dennis Bodewits說:“我們喜歡把2I/Borisov比作來自黑暗和寒冷地方的雪人。”他是發(fā)表在《自然天文學》雜志上的兩篇2I/Borisov研究論文之一的主要作者。

The comet, detected in August 2019 by amateur astronomer Gennady Borisov and estimated to be about six-tenths of a mile (1-km) wide, has zoomed through interstellar space after being ejected from its original star system.

這顆彗星于2019年8月被業(yè)余天文學家根納季·鮑里索夫發(fā)現(xiàn)，據(jù)估計大約有1公里寬的0.6分之1英里，從原來的恒星系統(tǒng)中被拋出后，在星際空間中迅速移動。

It was born long ago in a rotating disc of gas and dust surrounding a newly formed star in a place that must have been rich in carbon monoxide, Bodewits said. That star may have been what is called an M-dwarf, far smaller and cooler than the sun and the smallest type of star that is known, Bodewits said.

Bodewits說，它很久以前就誕生在一個旋轉(zhuǎn)的圓盤里，周圍環(huán)繞著一顆新形成的恒星，那里一定富含一氧化碳。博德威特說，這顆恒星可能是所謂的“m -矮星”，比太陽小得多，溫度也低得多，是已知的最小的恒星類型。