Results 11 to 20 of about 351,916 (340)
The Molecular Cloud Lifecycle. [PDF]
Space Sci Rev, 2020 AbstractGiant molecular clouds (GMCs) and their stellar offspring are the building blocks of galaxies. The physical characteristics of GMCs and their evolution are tightly connected to galaxy evolution. The macroscopic properties of the interstellar medium propagate into the properties of GMCs condensing out of it, with correlations between e.g.
Chevance M +8 more
europepmc +6 more sources
Turbulent molecular clouds [PDF]
The Astronomy and Astrophysics Review, 2012 Stars form within molecular clouds but our understanding of this fundamental process remains hampered by the complexity of the physics that drives their evolution. We review our observational and theoretical knowledge of molecular clouds trying to confront the two approaches wherever possible.
Patrick Hennebelle +2 more
arxiv +9 more sources
Molecular clouds in the Galaxy [PDF]
The Astrophysical Journal, 1975 The J = 1 → 0 emission of CO has been surveyed in the galactic plane between ℓ = -10° and +90° with a U beam sampling every degree. Molecular clouds emitting in the CO line are plentiful over the inner region of the Galaxy. Their greatest number occurs in the galactic nucleus and at a radius of 5.5 kpc—a distribution similar to radio H II regions and ...
N. Z. Scoville, P. M. Solomon
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Angular Momentum in Giant Molecular Clouds. I. The Milky Way [PDF]
, 2011 We present a detailed analysis comparing the velocity fields in molecular clouds and the atomic gas that surrounds them in order to address the origin of the gradients. To that end, we present first-moment intensity-weighted velocity maps of the molecular clouds and surrounding atomic gas. The maps are made from high-resolution 13CO observations and 21-
Blitz +28 more
arxiv +3 more sources
Evolving Molecular Cloud Structure and the Column Density Probability Distribution Function [PDF]
, 2014 The structure of molecular clouds can be characterized with the probability distribution function (PDF) of the mass surface density. In particular, the properties of the distribution can reveal the nature of the turbulence and star formation present inside the molecular cloud.
Sills, Alison +2 more
arxiv +4 more sources
Possibilities for Methanogenic and Acetogenic Life in Molecular Clouds [PDF]
LifeAccording to panspermia, life on Earth may have originated from life forms transported through space from elsewhere. These life forms could have passed through molecular clouds, where the process of methanogenesis could have provided enough energy to ...
Lei Feng
doaj +2 more sources
The Influence of Non-Uniform Cloud Cover on Transit Transmission Spectra [PDF]
, 2015 We model the impact of non-uniform cloud cover on transit transmission spectra. Patchy clouds exist in nearly every solar system atmosphere, brown dwarfs, and transiting exoplanets. Our major findings suggest that fractional cloud coverage can exactly mimic high mean molecular weight atmospheres and vice-versa over certain wavelength regions, in ...
Line, Michael R., Parmentier, Vivien
arxiv +3 more sources
High Altitude Molecular Clouds [PDF]
The Astrophysical Journal, 1994 A population of molecular clouds with a significantly greater scale height than that of Giant Molecular Clouds has been identified by examining maps of the latitude distribution of the $^{12}CO(1-0)$ emission in the first quadrant of the Galaxy. These clouds are found by identifying emission more than 2.6 times the scale-height away from the galactic ...
arxiv +5 more sources
3D MC. I. X-Ray Tomography Begins to Unravel the 3D Structure of a Molecular Cloud in our Galaxy’s Center [PDF]
The Astrophysical Journal LettersAstronomers have used observations of the Galactic gas and dust via infrared, microwave, and radio to study molecular clouds in extreme environments such as the Galactic center.
Samantha W. Brunker +7 more
doaj +2 more sources
Molecular Clouds in Spiral Galaxies [PDF]
Symposium - International Astronomical Union, 1983 A large observational program investigating the 2.6 mm CO line in spiral galaxies is being conducted by myself and Nick Scoville using the 14 m telescope of the Five College Radio Astronomy Observatory (HPBW = 50″). Thus far we have observed 46 galaxies of types Sa, Sb, Sc and Irr, detected 31, and mapped 16.
Judith S. Young
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