ヘイル・ボップ彗星の二つの一酸化炭素の源を特定した
M A DiSanti1, M J Mumma, N Dello Russo
1Department of Physics, The Catholic University of America, Washington, DC 20064, USA. disanti@kuiper.gsfc.nasa.gov
Nature
|June 29, 1999
まとめ
ヘール・ボップ彗星
科学分野:
- 天文学と天体物理学について
- 惑星科学は惑星科学である.
- アストロケミストリー アストロケミストリー
背景:
- 彗星の氷の組成は,太陽系形成のヒントを提供します.
- 水に対する一酸化炭素 (CO) の豊富さは,彗星以前の物質処理を示しています.
- これまでの彗星の氷のCO測定は曖昧でした.
研究 の 目的:
- ヘール・ボップ彗星の氷の原生CO2濃度を測定するために.
- 彗星前物質の化学処理への影響を評価する.
- 原子核から発生したCOとコマを区別するために.
主な方法:
- ヘール・ボップ彗星のインシトゥー観測.
- 水氷に対するCO濃度の分析.
- 分子雲と原型恒星の封筒組成との比較.
主要な成果:
- ヘイル・ボップ彗星の約50%のCO2は,核の氷から直接発生しています.
- 氷のCOと水の比率は12%で,静止している分子雲よりも低い.
- この比率は,原型恒星の封筒に存在する量と一致しています.
結論:
- ヘイル・ボップの彗星氷は,蓄積前の処理の証拠を示しています.
- 観測されたCOの豊富さは,原始恒星の封筒内の形成条件を示唆しています.
- 昏睡状態でのさらなる処理が,残ったCOの原因である可能性が高い.
さらに関連する動画
08:12Characterization, Quantification and Compound-specific Isotopic Analysis of Pyrogenic Carbon Using Benzene Polycarboxylic Acids (BPCA)
Published on: May 16, 2016
10:22Split Point Analysis and Uncertainty Quantification of Thermal-Optical Organic/Elemental Carbon Measurements
Published on: September 7, 2019
関連する概念動画
02:39Emission Spectra
When solids, liquids, or condensed gases are heated sufficiently, they radiate some of the excess energy as light. Photons produced in this manner have a range of energies, and thereby produce a continuous spectrum in which an unbroken series of wavelengths is present.
01:13¹H NMR: Complex Splitting
A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
01:10Detection of Black Holes
Although black holes were theoretically postulated in the 1920s, they remained outside the domain of observational astronomy until the 1970s.
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
01:04¹³C NMR: ¹H–¹³C Decoupling
The probability of having two carbon-13 atoms next to each other is negligible because of the low natural abundance of carbon-13. Consequently, peak splitting due to carbon-carbon spin-spin coupling is not observed in spectra. However, protons up to three sigma bonds away split the carbon signal according to the n+1 rule, resulting in complicated spectra.
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
01:22Atomic Emission Spectroscopy: Instrumentation
The instrumentation of atomic emission spectrometry (AES) involves various components, including atomization devices that convert samples into gas-phase atoms and ions. There are two main types of atomization devices: continuous and discrete atomizers. Continuous atomizers, like plasmas and flames, introduce samples in a constant stream, while discrete atomizers inject individual samples using syringes or autosamplers. The most common discrete atomizer is the electrothermal atomizer.
01:30Atomic Emission Spectroscopy: Interference
In atomic emission spectroscopy (AES), high-temperature atomizers excite a broad range of elements and molecules that generate complex emissions from sources such as oxides, hydroxides, and flame combustion products in the flame or plasma. Several strategies can be employed to minimize spectral interferences caused by overlapping emission lines or bands. These include increasing instrument resolution, choosing alternative emission lines, optimally placing the detector in low-background regions,...