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DennisN
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(@mfb posted an article about this here, I think it deserves an own thread, and I did not find one, so I start one )
The comet-like composition of a protoplanetary disk as revealed by complex cyanides
Karin I. Öberg, Viviana V. Guzmán, Kenji Furuya, Chunhua Qi, Yuri Aikawa, Sean M. Andrews, Ryan Loomis & David J. Wilner
Nature 520, 198–201 (09 April 2015) doi:10.1038/nature14276
Abstract:
"Observations of comets and asteroids show that the solar nebula that spawned our planetary system was rich in water and organic molecules. Bombardment brought these organics to the young Earth’s surface. Unlike asteroids, comets preserve a nearly pristine record of the solar nebula composition. The presence of cyanides in comets, including 0.01 per cent of methyl cyanide (CH3CN) with respect to water, is of special interest because of the importance of C–N bonds for abiotic amino acid synthesis. Comet-like compositions of simple and complex volatiles are found in protostars, and can readily be explained by a combination of gas-phase chemistry (to form, for example, HCN) and an active ice-phase chemistry on grain surfaces that advances complexity. Simple volatiles, including water and HCN, have been detected previously in solar nebula analogues, indicating that they survive disk formation or are re-formed in situ. It has hitherto been unclear whether the same holds for more complex organic molecules outside the solar nebula, given that recent observations show a marked change in the chemistry at the boundary between nascent envelopes and young disks due to accretion shocks. Here we report the detection of the complex cyanides CH3CN and HC3N (and HCN) in the protoplanetary disk around the young star MWC 480. We find that the abundance ratios of these nitrogen-bearing organics in the gas phase are similar to those in comets, which suggests an even higher relative abundance of complex cyanides in the disk ice. This implies that complex organics accompany simpler volatiles in protoplanetary disks, and that the rich organic chemistry of our solar nebula was not unique."
Paper (Nature, and behind paywall):
http://www.nature.com/nature/journal/v520/n7546/full/nature14276.html
Paper (ALMA, open access):
www.almaobservatory.org/images/newsreleases/ALMA_nature_oberg012415.pdf
Article 1: "Complex organic molecules discovered in infant star system: Hints that building blocks of chemistry of life are universal" (ScienceDaily)
Article 2: "Complex organic molecules discovered in infant star system" (PhysOrg)
Pretty interesting, I think...
Edit: Found another article on the ALMA site:
"Complex Organic Molecules Discovered in Infant Star System: Hints that Prebiotic Chemistry Is Universal" (08 April 2015)
Quote from the ALMA article: "For the first time, astronomers have detected the presence of complex organic molecules, the building blocks of life, in a protoplanetary disk surrounding a young star, suggesting once again that the conditions that spawned our Earth and Sun are not unique in the Universe."
The comet-like composition of a protoplanetary disk as revealed by complex cyanides
Karin I. Öberg, Viviana V. Guzmán, Kenji Furuya, Chunhua Qi, Yuri Aikawa, Sean M. Andrews, Ryan Loomis & David J. Wilner
Nature 520, 198–201 (09 April 2015) doi:10.1038/nature14276
Abstract:
"Observations of comets and asteroids show that the solar nebula that spawned our planetary system was rich in water and organic molecules. Bombardment brought these organics to the young Earth’s surface. Unlike asteroids, comets preserve a nearly pristine record of the solar nebula composition. The presence of cyanides in comets, including 0.01 per cent of methyl cyanide (CH3CN) with respect to water, is of special interest because of the importance of C–N bonds for abiotic amino acid synthesis. Comet-like compositions of simple and complex volatiles are found in protostars, and can readily be explained by a combination of gas-phase chemistry (to form, for example, HCN) and an active ice-phase chemistry on grain surfaces that advances complexity. Simple volatiles, including water and HCN, have been detected previously in solar nebula analogues, indicating that they survive disk formation or are re-formed in situ. It has hitherto been unclear whether the same holds for more complex organic molecules outside the solar nebula, given that recent observations show a marked change in the chemistry at the boundary between nascent envelopes and young disks due to accretion shocks. Here we report the detection of the complex cyanides CH3CN and HC3N (and HCN) in the protoplanetary disk around the young star MWC 480. We find that the abundance ratios of these nitrogen-bearing organics in the gas phase are similar to those in comets, which suggests an even higher relative abundance of complex cyanides in the disk ice. This implies that complex organics accompany simpler volatiles in protoplanetary disks, and that the rich organic chemistry of our solar nebula was not unique."
Paper (Nature, and behind paywall):
http://www.nature.com/nature/journal/v520/n7546/full/nature14276.html
Paper (ALMA, open access):
www.almaobservatory.org/images/newsreleases/ALMA_nature_oberg012415.pdf
Article 1: "Complex organic molecules discovered in infant star system: Hints that building blocks of chemistry of life are universal" (ScienceDaily)
Article 2: "Complex organic molecules discovered in infant star system" (PhysOrg)
Pretty interesting, I think...
Edit: Found another article on the ALMA site:
"Complex Organic Molecules Discovered in Infant Star System: Hints that Prebiotic Chemistry Is Universal" (08 April 2015)
Quote from the ALMA article: "For the first time, astronomers have detected the presence of complex organic molecules, the building blocks of life, in a protoplanetary disk surrounding a young star, suggesting once again that the conditions that spawned our Earth and Sun are not unique in the Universe."
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