Passing through a giant molecular cloud: “Snowball” glaciations produced by interstellar dust
نویسندگان
چکیده
منابع مشابه
Neoproterozoic ‘snowball Earth’ glaciations and the evolution of altruism
We hypothesize that a demographic and ecological effect of Neoproterozoic ‘snowball Earth’ glaciations was to increase the fitness of group-level traits and consequently the likelihood of the evolution of macroscopic form. Extreme and repeated founder effects raised genetic relatedness – and therefore the influence of kin selection on the individuals within a group. This was permissive for the ...
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متن کاملInterstellar Dust
In the interstellar medium of the Milky Way, certain elements – e.g., Mg, Si, Al, Ca, Ti, Fe – reside predominantly in interstellar dust grains. These grains absorb, scatter, and emit electromagnetic radiation, heat the interstellar medium by photoelectric emission, play a role in the ionization balance of the gas, and catalyze the formation of molecules, particularly H2. I review the state of ...
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We present 45-47 angular resolution maps at 50 sampling of the CO and CO J=1-0 emission toward a 1.39 × 1.33 region in the W51 H II region complex. These data permit the spatial and kinematic separation of several spectral features observed along the line of sight to W51, and establish the presence of a massive (1.2 × 10 M⊙), large (∆l × ∆b = 83pc × 114 pc) giant molecular cloud (GMC), defined ...
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ژورنال
عنوان ژورنال: Geophysical Research Letters
سال: 2005
ISSN: 0094-8276
DOI: 10.1029/2004gl021890