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Six-Decade-Old Space Mystery Solved With Shoebox-Sized Satellite Called A CubeSat(图)
Six Decade Old Space Mystery Shoebox-Sized Satellite CubeSat
2017/12/19
A 60-year-old mystery about the source of energetic, potentially damaging particles in Earth's radiation belts has been solved using data from a shoebox-sized satellite built and operated by students....
Map of Mysterious Molecules In Our Galaxy Sheds New Light on Century-Old Puzzle(图)
Map of Mysterious Molecules Our Galaxy Light on Century-Old Puzzle
2015/1/20
The map, which can be viewed at http://is.gd/dibmap, was unveiled Jan. 8 at the 225th meeting of the American Astronomical Society in Seattle. The map will be discussed at a 2:15 p.m. PST press confer...
Some 30 years ago, astronomers found that regions of ionized gas around young high mass stars remain small (under a third of a light-year) for ten times longer than they should if they were to expand ...
Stellar lifetime and ultraviolet properties of the old metal-rich Galactic open cluster NGC6791: a pathway to understand the UV upturn of elliptical galaxies
Stellar lifetime ultraviolet properties old metal-rich Galactic cluster NGC6791 UV upturn elliptical galaxies
2012/2/23
The evolutionary properties of the old metal-rich Galactic open cluster NGC6791 are assessed, based on deep UB photometry and 2Mass JK data. For 4739 stars in the cluster, bolometric luminosity and ef...
The Young, the Old, and the Dusty: Stellar Populations of AGN Hosts
Dusty: Stellar Populations AGN Hosts
2011/10/11
Studying the average properties of active galactic nuclei (AGN) host stellar populations is an important step in understanding the role of AGN in galaxy evolution and the processes which trigger and f...
Segue 3: An Old, Extremely Low luminosity Star Cluster in the Milky Way's Halo
Extremely luminosity Star Cluster Milky Way
2011/10/10
We investigate the kinematic and photometric properties of the Segue 3 Milky Way companion using Keck/DEIMOS spectroscopy and Magellan/IMACS g and r-band imaging. Using maximum likelihood methods to a...
Star Clusters in M31: Old Clusters with Bar Kinematics
catalogs – galaxies individual (M31) – galaxies star clusters – globular clusters
2010/11/12
We analyze our accurate kinematical data for the old clusters in the inner regions of M31. These velocities are based on high S/N Hectospec data (Caldwell et al 2010). The data are well suited for ana...
Old open clusters and the Galactic metallicity gradient: Berkeley 20, Berkeley 66, and Tombaugh 2
Galaxy disc – Hertzsprung-Russell (HR) diagram – open clusters and associations
2010/11/15
To study the crucial range of Galactocentric distances between 12 and 16 kpc, where little
information is available, we have obtained V I CCD imaging of Berkeley 20 and BV I CCD
imaging of Berkeley ...
Old White Dwarf Stars with Some Hydrogen -- Cooling Curves
Solar and Stellar Astrophysics (astro-ph.SR)
2011/1/6
We present theoretical analysis on old white dwarf stars with \emph{some} hydrogen, that possess a mass of surface hydrogen from $1\times10^{-11}M_{\sun}$ to $1\times10^{-7}M_{\sun}$. The evolution of...
Formation Efficiencies of Old Globular Clusters - from Dwarf to Giant Galaxies
Cosmology and Extragalactic Astrophysics (astro-ph.CO) Galaxy Astrophysics (astro-ph.GA)
2011/1/6
For the full galaxy mass range, we find that previously observed trends of globular cluster (GC) system scaling parameters (number, luminosity or mass of all GCs in a galaxy normalized to the host gal...
Debris discs in the 27 Myr old open cluster IC4665
Solar and Stellar Astrophysics (astro-ph.SR)
2010/12/28
We present Spitzer IRAC and MIPS 24um imaging of members of the 27+/-5Myr old open cluster IC 4665. Models for the assembly of terrestrial planets through planetesimal collisions and mergers predict e...
Internal Heating of Old Neutron Stars: Contrasting Different Mechanisms
stars neutron dense matter stars rotation pulsars general pulsars individual (PSR J0437-4715)
2010/3/9
The thermal emission detected from the millisecond pulsar J0437-4715 is not explained by standard cooling models of neutron stars without a heating mechanism. We investigated three heating mechanisms ...
HerMES team member Dimitra Rigopoulou, of Oxford University's Department of Physics and the Rutherford Appleton Laboratory, told me: 'It is a tremendous leap forward for understanding how galaxies for...
Probing structure and populations of our Galaxy using the kinematics of old stars. II
Probing structure kinematics of old stars Galaxy
2009/6/30
Probing structure and populations of our Galaxy using the kinematics of old stars. II。
Probing structure and populations of our Galaxy using the kinematics of old stars. I
Probing structure kinematics of old stars Galaxy
2009/6/30
Probing structure and populations of our Galaxy using the kinematics of old stars. I。