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Chemical trail on Titan may be key to prebiotic conditions
Chemical trail Titan prebiotic conditions
2016/7/15
NASA’s Cassini and Huygens missions have provided a wealth of data about chemical elements found on Saturn’s moon Titan, and Cornell scientists have uncovered a chemical trail that suggests prebiotic ...
New Theory Turns Back Clock on Conditions Behind Universe's Origin
Turns Back Clock Universe's Origin
2016/2/22
In a new study, scientists from The University of Texas at Dallas and their colleagues suggest a novel way for probing the beginning of space and time, potentially revealing secrets about the conditio...
Crater clusters on Mars:Shedding light on martian ejecta launch conditions
Cratering Mars Meteorites Impact processes
2015/12/25
We have identified two classes of crater clusters on Mars. One class is “small clusters” (crater diameter D ～ tens m, spread over few hundred m), fitting our earlier calculations for the breakup of we...
The intergalactic medium over the last 10 billion years I: Lyman alpha absorption and physical conditions
intergalactic medium hydrodynamic
2014/12/20
The intergalactic medium (IGM) is the dominant reservoir of baryons at all cosmic epochs. We investigate the evolution of the IGM from z=2-0 in 48 Mpc/h, 110-million particle cosmological hydrodynamic...
Observing Conditions for Submillimeter Astronomy
Atmospheric e ects Site testing Submillimeter general
2011/10/20
Consistently superb observing conditions are crucial for achieving the scientific objectives of a telescope. Submillimeter astronomy is possible only at a few exceptionally dry sites, notably Mauna Ke...
Searching for dark matter isocurvature initial conditions with N-body Simulations
Searching dark matter isocurvature initial conditions N-body Simulations
2011/10/12
Small fraction of isocurvature perturbations may exist and correlate with adiabatic perturbations in the primordial perturbations. Naively switching off isocurvature perturbations may lead to biased r...
BLR Physical Conditions in Extreme Population A Quasars: a Method to Estimate Central Black Hole Mass at High Redshift
Physical Conditions Extreme Population Quasars
2011/10/10
We describe a method for determination of physical conditions in the broad line regions of a significant subsample of Seyfert-1 nuclei and quasars. Several diagnostic ratios based on intermediate (AlI...
General conditions for scale-invariant perturbations in an expanding universe
General conditions scale-invariant perturbations expanding universe
2011/9/29
We investigate the general properties of expanding cosmological models which generate scale-invariant curvature perturbations in the presence of a variable speed of sound. We show that in an expanding...
Probing cluster formation under extreme conditions: massive star clusters in blue compact galaxies
galaxies: starburst - galaxies: star clusters: general - galaxies: irregular- galaxies:star formation
2011/9/27
The numerous and massive young star clusters in blue compact galaxies (BCGs) are used to investigate the properties of their hosts. We test whether BCGs follow claimed relations between cluster popula...
MHD Simulations of Parker Instability Undergoing Cosmic-Ray Diffusion: Effect of the Initial Equilibrium Conditions on Mixing
cosmic rays magnetohydrodynamics instability numerical simulation
2010/11/9
Parker instability arises from the presence of magnetic fields in a plasma such as the interstellar medium (ISM),wherein the magnetic buoyant pressure expels the gas and causes the gas to move along t...
Panspermia, Past and Present: Astrophysical and Biophysical Conditions for the Dissemination of Life in Space
Radiation pressure Cosmic rays Micro-organisms Viruses Information
2010/11/9
Astronomically, there are viable mechanisms for distributing organic material throughout the Milky Way. Biologically, the destructive effects of ultraviolet light and cosmic rays means that the majori...
Spitzer observations of supernova remnants: II. Physical conditions and comparison with HH7 and HH54
molecular — ISM abundance — ISM clouds molecular processes shock waves
2010/11/9
We have studied the shock-excited molecular regions associated with four supernova remnants (SNRs) — IC443C, W28, W44 and 3C391 — and two Herbig-Haro objects,HH7 and HH54, using Spitzer ’s Infrared Sp...
Extreme conditions in natural flows are examined, starting with a turbulent big bang.A hydro-gravitational-dynamics cosmology model is adopted. Planck-Kerr turbulence instability causes Planck-particl...
Time-variability in the Interstellar Boundary Conditions of the Heliosphere over the past 60,000 years: Impact of the Solar Journey on the Galactic Cosmic Ray Flux at Earth
Time-variability the Interstellar Boundary Conditions
2011/1/10
During the solar journey through galactic space, variations in the physical properties of the surrounding interstellar material (ISM) modify the heliosphere and modulate the flux of galactic cosmic ra...
High-resolution mapping of the physical conditions in two nearby active galaxies based on 12CO(1-0), (2-1) and (3-2) lines
Galaxy Astrophysics (astro-ph.GA)
2010/12/29
We present a detailed analysis of high resolution observations of the three lowest CO transitions in two nearby active galaxies, NGC4569 and NGC4826. The CO(1-0) and (2-1) lines were observed with the...