相关论文: End-cretaceous cooling and mass extinction driven …
The central parsec of the Galaxy contains a young star cluster embedded in a complex interstellar medium. The latter mainly consists of a torus of dense clumps and streams of molecular gas (the circumnuclear disk, CND) enclosing streamers…
Despite tremendous interest in the topic and decades of research, the origins of the major losses of biodiversity in the history of life on Earth remain elusive. A variety of possible causes for these mass-extinction events have been…
The discoveries of huge amounts of dust and unusual extinction curves in high-redshift quasars (z > 4) cast challenging issues on the origin and properties of dust in the early universe. In this Letter, we investigate the evolutions of dust…
Using star counts in both color and magnitude from the Two Micron All Sky Survey (2MASS) Second Incremental Release Point Source Catalog we search for evidence of non-uniform extinction and stellar population density changes in the Galactic…
We present a new version of our analytical model of the spatial interstellar extinction variations within the nearest kiloparsec. This model treats the 3D dust distribution as a superposition of three overlapping layers: (1) the layer along…
A high fraction of carbon bound in solid carbonaceous material is observed to exist in bodies formed in the cold outskirts of the solar nebula, while bodies in the terrestrial planets region contain nearly none. We study the fate of the…
In Arctic East Siberia many remains of mammoths have been found. In this region there is not sufficient sunlight over the year to allow for the growth of the plants on which these animals feed. Consequently the latitude of these regions…
Massive stars (M $\gsim 10$ \msun) form from collapse of parsec-scale molecular clumps. How molecular clumps fragment to give rise to massive stars in a cluster with a distribution of masses is unclear. We search for cold cores that may…
The zodiacal cloud is a thick circumsolar disk of small debris particles produced by asteroid collisions and comets. Here, we present a zodiacal cloud model based on the orbital properties and lifetimes of comets and asteroids, and on the…
The recent publication by Siraj & Loeb (2021; Nature Scientific Reports 11, 3803) attempts to revive the debate over whether the Chicxulub impactor was a comet or an asteroid. They calculate that ~20% of long-period comets impacting Earth…
Continuum observations at 350um are presented of seven nearby elliptical galaxies, for which CO-gas disks have recently been resolved with interferometry mapping. These SHARCII mapping results provide the first clearly resolved…
We have studied the interstellar extinction in a field of 3' x 3' located about 6' SW of 30 Doradus in the Large Magellanic Cloud (LMC). Hubble Space Telescope observations in the U, B, V, I and Halpha bands reveal patchy extinction in this…
Recent XMM-Newton observations of clusters of galaxies have provided detailed information on the distribution of heavy elements in the central regions of clusters with cooling cores providing strong evidence that most of these metals come…
Observations of exoplanet atmospheres have revealed the presence of cloud particles in their atmospheres. 3D modelling of cloud formation in atmospheres of extrasolar planets coupled to the atmospheric dynamics has long been a challenge. We…
Inversion of interstellar gas or dust columns measured along the path to stars distributed in distance and direction allows reconstructing the distribution of interstellar matter (ISM) in 3D. A low resolution IS dust map based on the…
The shape of the cold interstellar molecular gas is determined by several processes, including self-gravity, tidal force, turbulence, magnetic field, and galactic shear. Based on the 3D dust extinction map derived by Vergely et al., we…
Context: Molecular data of extreme environments, such as Arp 220, but also NGC 253, show evidence for extremely high cosmic ray (CR) rates (10^3-10^4 * Milky Way) and mechanical heating from supernova driven turbulence. Aims: The…
We analyze extragalactic extinction profiles derived through gamma-ray burst afterglows, using a dust model specifically constructed on the assumption that dust grains are not immutable but respond time-dependently to the local physics.…
This review describes our current understanding of interstellar extinction. This differ substantially from the ideas of the 20th century. With infrared surveys of hundreds of millions of stars over the entire sky, such as 2MASS,…
Cosmological models with cosmic string and texture seeded universes predict a present abundance of very dense clumps of Cold Dark Matter particles. Their crossing through the solar system would induce a non-negligible amount of radiation…