典型的な恒星形成銀河の形成と集合は,赤道偏移zzで約3で発生する
Daniel P Stark1, A Mark Swinbank, Richard S Ellis
1Department of Astronomy, California Institute of Technology, Pasadena, California 91125, USA. dps@astro.caltech.edu
Nature
|October 10, 2008
まとめ
ビッグバンから2~30億年後に観測された銀河盤は,銀河の成長を促すのは,合併ではなく,ガスの蓄積であると示唆しています. この研究は,典型的な銀河についてこれを確認し,回転するガスディスクで効率的な星形成を明らかにしています.
科学分野:
- 銀河の宇宙進化について
- 銀河の形成と進化について
- 天体物理学 天体物理学
背景:
- 初期の銀河 (ビッグバン後の2〜3ギア) は,大きな回転する円盤を示しており,これは合併によるガス蓄積を暗示しています.
- 以前の研究は,明るく輝く銀河に限られており,典型的な銀河の集合体を表していない可能性があります.
- 高解像度観測は,明るさが低い銀河の成長を理解するために不可欠です.
研究 の 目的:
- 高赤偏移 (z = 3.07) で典型的な恒星形成銀河の成長メカニズムを調査する.
- これらの銀河におけるガスと恒星形成の空間構造とダイナミクスを解明するために.
- 大規模な合併よりもガスの蓄積が銀河の成長を支配するという仮説を検証するために.
主な方法:
- z = 3.07.の典型的な恒星形成銀河の高解像度観測.
- 分子ガスの含有量と恒星形成率の分析.
- 銀河の速度場と構造の詳細な調査.
主要な成果:
- 典型的な銀河のコンパクトで秩序ある回転源の観測.
- この源の中で分子ガスを星に効率的に変換する.
- 現在の渦巻き銀河に似た,球形状の膨張が形成されている証拠.
結論:
- ガス蓄積は,初期の宇宙時代にさえも,典型的な銀河の成長のための重要なメカニズムです.
- 観測された回転は,大規模な合併がそのような銀河の質量アセンブリの主な原動力ではないことを示唆しています.
- これらの発見は,銀河系のような銀河が連続したガス流入によって質量を蓄積するモデルを裏付けている.
関連する概念動画
Formation of Species
47.0K
Speciation describes the formation of one or more new species from one or sometimes multiple original species. The resulting species are discrete from the parent species, and barriers to reproduction will typically exist. There are two primary mechanisms, speciation with and without geographic isolation—allopatric and sympatric speciation, respectively.
47.0K
Formation of Higher-order Actin Filaments
3.9K
The polymerization of G-actin monomers into filamentous F-actin is a multi-step process. Once the F-actins are formed, they can bundle together in different arrangements to form higher-order networks and regulate cellular functions. Common examples include the formation of lamellipodia and filopodia at the cell's leading edge by actin reorganization in a migrating cell. The microvilli on the brush border epithelial cells are also formed through the F-actin network.
The high-order actin...
The high-order actin...
3.9K
Microtubule Formation
8.2K
Microtubules are dynamic structures that undergo continuous assembly and disassembly. They originate from specialized multi-protein complexes known as microtubule organizing centers or MTOCs. Within the MTOC, the point of origin of the microtubule is known as the minus end, while the end radiating outward is the plus end. Microtubules serve two primary functions — the organization of spindle complexes to separate sister chromatids during mitotic or meiotic cell division and the formation...
8.2K
Formation of Intermediate Filaments
4.2K
Intermediate filaments are cytoskeletal proteins with higher tensile strength and flexibility than microfilaments and microtubules. Unlike the other two cytoskeletal proteins, intermediate filament formation lacks the enzymatic activity to hydrolyze nucleotides like ATP and GTP to generate energy for polymerization. Therefore, the formation of intermediate filaments is multistep self-assembly. The involvement of any accessory proteins in intermediate filament formation has not yet been...
4.2K
Detection of Black Holes
2.6K
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...
2.6K
Zygotic Development And Stem Cell Formation
7.6K
The development of all multicellular organisms starts with the fusion of haploid cells called sperm and egg to form a diploid zygote. A zygote is a totipotent cell that can develop into a complete organism. The zygote undergoes cell division or cleavage to form an 8-cell mass. Until this stage, the cells are spherical, loosely attached, and remain totipotent. Totipotent cells are capable of developing both the embryonic and the extraembryonic tissues. However, as they continue to divide, they...
7.6K


