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1)Meteorites on the ground or icy comets millions of miles away are usually the only sources of ancient matter from the early days of the solar system.
But in a high-flying experiment, researchers have used a sort of chemical 2)flypaper to 3)scoop up comet dust from Earth’s atmosphere – and it appears to be some of the oldest matter in our cosmic neighborhood.
The ancient specks, some of which are more than 4.5 billion years old, may support the theory that an exploding star helped 4)trigger the birth of our sun.
The dust has survived in an 5)unaltered state for so long because it got swept up during the formation of icy comets, researchers say.
“Comets are like refrigerators for this material,” said study leader Henner Busemann, an 6)astrophy-sicist at the University of Manchester in the U.K.
“They store this very 7)pristine material, which never changes again.”
Dust from the Sun’s 8)Nursery Busemann and colleagues collected the particles in April 2003, as Earth spun through the dusty tail of comet 26P/Grigg-Skjellerup.
The team asked NASA to fly an airplane at about 12 miles (20 kilometers) up for several hours during the comet’s visit, using instruments equipped with silicon oil to capture particles trapped in the upper atmosphere.
By comparing the dust to samples collected from comet-9)smashing 10)probes such as Deep Impact and Stardust, the scientists were able to tell that the particles in Earth’s atmosphere came from 26P/Grigg-Skjellerup.
The team’s analysis also shows that two of the grains have a unique chemical fingerprint linking them to the huge gas cloud. Scientists think it was our sun’s 11)stellar nursery.
Also, one of the dust particles contains grains of material that match predictions for the types of matter expected to form in the cooling gas left over after a 12)supernova explosion.
Scientists have 13)speculated that 14)shockwaves from a nearby supernova helped trigger the birth of our sun, and some of the comet material could have originated from that blast, Busemann said.
The astrophysicist presented his research this April at the European Week of Astronomy and Space Science conference at the University of Hertfordshire in the U.K.
地面上的陨星或几百万英里外的冰状彗星往往是太阳系初期远古物质的唯一来源。
不过,在一项高空飞行的实验环境下,研究人员使用了一种化学“捕蝇纸”收集到来自地球大气层的彗星尘埃——它可能是我们的宇宙邻域中最为古老的物质。
部分远古尘埃已有超过45亿年的历史。这也许能支持“某一恒星的爆炸促成了太阳系的诞生”此理论假说。
研究人员称,这种尘埃在恒定不变的状态下存活了非常长的时间,因为早在冰状彗星形成的时候,它就被清理一新了。
“彗星就像是储存这种物质的冰箱,”来自英国曼彻斯特大学的天体物理学家、研究组负责人亨纳·布兹曼说。
“它们将这种远古的物质储存起来,这些物质再也不会发生变化了。”
来自太阳温床的尘埃
2003年4月,当地球旋转经过格里格-斯克杰利厄普彗星的尘埃尾部时,布兹曼及其同事收集了一些粒子。
在该彗星经过地球期间,研究小组请美国国家航空航天局(NASA)发射一架航天飞机,在大约12英里(20公里)高的高空飞行几小时,用装有硅油的设备捕获被诱入大气层上部的粒子。
通过将这种尘埃与从彗星破碎探测器如“深度撞击号”和“星尘号”等收集来的样本进行比较,科学家们得出结论,这些出现在地球大气层的粒子均来自格里格-斯克杰利厄普彗星。
该研究小组的分析还显示,其中两个颗粒上拥有与大型气体云有联系的独特化学“指纹”。科学家们认为这种气体云是孕育太阳的温床。
此外,其中一个尘埃还包含了一些物质颗粒,这些颗粒证实了对超新星爆炸后留存下来的冷却气体中形成的物质类别的预测。
布兹曼说,科学家们猜测,来自一颗邻近超新星的冲击波促成了我们太阳系的诞生,一些彗星物质可能产生于这次大爆炸。
今年四月,这位天文物理学家在英国赫特福德大学举行的欧洲天文周和太空科学大会上展示了他的研究结果。
But in a high-flying experiment, researchers have used a sort of chemical 2)flypaper to 3)scoop up comet dust from Earth’s atmosphere – and it appears to be some of the oldest matter in our cosmic neighborhood.
The ancient specks, some of which are more than 4.5 billion years old, may support the theory that an exploding star helped 4)trigger the birth of our sun.
The dust has survived in an 5)unaltered state for so long because it got swept up during the formation of icy comets, researchers say.
“Comets are like refrigerators for this material,” said study leader Henner Busemann, an 6)astrophy-sicist at the University of Manchester in the U.K.
“They store this very 7)pristine material, which never changes again.”
Dust from the Sun’s 8)Nursery Busemann and colleagues collected the particles in April 2003, as Earth spun through the dusty tail of comet 26P/Grigg-Skjellerup.
The team asked NASA to fly an airplane at about 12 miles (20 kilometers) up for several hours during the comet’s visit, using instruments equipped with silicon oil to capture particles trapped in the upper atmosphere.
By comparing the dust to samples collected from comet-9)smashing 10)probes such as Deep Impact and Stardust, the scientists were able to tell that the particles in Earth’s atmosphere came from 26P/Grigg-Skjellerup.
The team’s analysis also shows that two of the grains have a unique chemical fingerprint linking them to the huge gas cloud. Scientists think it was our sun’s 11)stellar nursery.
Also, one of the dust particles contains grains of material that match predictions for the types of matter expected to form in the cooling gas left over after a 12)supernova explosion.
Scientists have 13)speculated that 14)shockwaves from a nearby supernova helped trigger the birth of our sun, and some of the comet material could have originated from that blast, Busemann said.
The astrophysicist presented his research this April at the European Week of Astronomy and Space Science conference at the University of Hertfordshire in the U.K.
地面上的陨星或几百万英里外的冰状彗星往往是太阳系初期远古物质的唯一来源。
不过,在一项高空飞行的实验环境下,研究人员使用了一种化学“捕蝇纸”收集到来自地球大气层的彗星尘埃——它可能是我们的宇宙邻域中最为古老的物质。
部分远古尘埃已有超过45亿年的历史。这也许能支持“某一恒星的爆炸促成了太阳系的诞生”此理论假说。
研究人员称,这种尘埃在恒定不变的状态下存活了非常长的时间,因为早在冰状彗星形成的时候,它就被清理一新了。
“彗星就像是储存这种物质的冰箱,”来自英国曼彻斯特大学的天体物理学家、研究组负责人亨纳·布兹曼说。
“它们将这种远古的物质储存起来,这些物质再也不会发生变化了。”
来自太阳温床的尘埃
2003年4月,当地球旋转经过格里格-斯克杰利厄普彗星的尘埃尾部时,布兹曼及其同事收集了一些粒子。
在该彗星经过地球期间,研究小组请美国国家航空航天局(NASA)发射一架航天飞机,在大约12英里(20公里)高的高空飞行几小时,用装有硅油的设备捕获被诱入大气层上部的粒子。
通过将这种尘埃与从彗星破碎探测器如“深度撞击号”和“星尘号”等收集来的样本进行比较,科学家们得出结论,这些出现在地球大气层的粒子均来自格里格-斯克杰利厄普彗星。
该研究小组的分析还显示,其中两个颗粒上拥有与大型气体云有联系的独特化学“指纹”。科学家们认为这种气体云是孕育太阳的温床。
此外,其中一个尘埃还包含了一些物质颗粒,这些颗粒证实了对超新星爆炸后留存下来的冷却气体中形成的物质类别的预测。
布兹曼说,科学家们猜测,来自一颗邻近超新星的冲击波促成了我们太阳系的诞生,一些彗星物质可能产生于这次大爆炸。
今年四月,这位天文物理学家在英国赫特福德大学举行的欧洲天文周和太空科学大会上展示了他的研究结果。