The close circumstellar environment of Betelgeuse
... Conclusions. The circumstellar envelope around Betelgeuse extends at least up to several tens of stellar radii. Its relatively high degree of clumpiness indicates an inhomogeneous spatial distribution of the material lost by the star. Its extension corresponds to an important intermediate scale, whe ...
... Conclusions. The circumstellar envelope around Betelgeuse extends at least up to several tens of stellar radii. Its relatively high degree of clumpiness indicates an inhomogeneous spatial distribution of the material lost by the star. Its extension corresponds to an important intermediate scale, whe ...
Some Constraints on the Effects of Age and Metallicity - UvA-DARE
... SOME CONSTRAINTS ON THE EFFECTS OF AGE AND METALLICITY ON THE LOW-MASS X-RAY BINARY FORMATION RATE1 Arunav Kundu,2 Thomas J. Maccarone,3 Stephen E. Zepf,2 and Thomas H. Puzia4 ...
... SOME CONSTRAINTS ON THE EFFECTS OF AGE AND METALLICITY ON THE LOW-MASS X-RAY BINARY FORMATION RATE1 Arunav Kundu,2 Thomas J. Maccarone,3 Stephen E. Zepf,2 and Thomas H. Puzia4 ...
Fast Auto-Focus Method and Software for CCD
... 2. A full frame 3x3 binned image is taken with a minimal exposure time 3. The brightest star is found, the position determined and the HFD measured 4. The target star is sub-framed and a second exposure taken (download time is minimized due to the smaller frame size) 5. The focuser position is then ...
... 2. A full frame 3x3 binned image is taken with a minimal exposure time 3. The brightest star is found, the position determined and the HFD measured 4. The target star is sub-framed and a second exposure taken (download time is minimized due to the smaller frame size) 5. The focuser position is then ...
The mass-loss return from evolved stars to the Large Magellanic Cloud
... The study of Milky Way AGB stars is inhibited by the presence of substantial interstellar extinction, and large uncertainties in distance determinations. The Large Magellanic Cloud (LMC) offers the combination of proximity (∼50 kpc; van Leeuwen et al. 2007), low line-of-sight extinction (E(B − V) ∼ 0 ...
... The study of Milky Way AGB stars is inhibited by the presence of substantial interstellar extinction, and large uncertainties in distance determinations. The Large Magellanic Cloud (LMC) offers the combination of proximity (∼50 kpc; van Leeuwen et al. 2007), low line-of-sight extinction (E(B − V) ∼ 0 ...
[C ii] 157 μm Emission in a Five-component Interstellar
... originates from the photons of massive young stars. For simplicity we do not takeother sources of mechanical heating into account, i.e., turbulence, which can also be important to the physics and chemistry of the ISM phases, as has been seen in the high-latitude Galatic diffuse clouds (Ingalls et a ...
... originates from the photons of massive young stars. For simplicity we do not takeother sources of mechanical heating into account, i.e., turbulence, which can also be important to the physics and chemistry of the ISM phases, as has been seen in the high-latitude Galatic diffuse clouds (Ingalls et a ...
Activity III: Calibrating Images
... that has traveled vast distances. Amazingly, the light remains virtually unaffected by the first 99.999999999999% or so of its journey. However, in the trip through the Earth’s atmosphere, and even through the optics of the telescope, the light may finally be affected causing the brightness of the s ...
... that has traveled vast distances. Amazingly, the light remains virtually unaffected by the first 99.999999999999% or so of its journey. However, in the trip through the Earth’s atmosphere, and even through the optics of the telescope, the light may finally be affected causing the brightness of the s ...
The effects of disk building on the distributions of refractory materials
... illustrated in Fig. 1. This dissipation operates even after the collapse stage stopped, and the central star continues to accrete mass from the disk. The transport of mass through the disk also determines the thermal environments within which planetary materials are processed. The disk is generally ...
... illustrated in Fig. 1. This dissipation operates even after the collapse stage stopped, and the central star continues to accrete mass from the disk. The transport of mass through the disk also determines the thermal environments within which planetary materials are processed. The disk is generally ...
PowerPoint file - Departament d`Astronomia i Meteorologia
... Weak continuum emission at 230 GHz (at a 6 level) is found associated with IRS 1 with a flux density of 18.3 mJy. For a dust temperature between 20 K (from NH3 Miralles et al. 1994) and 44 K (derived from the SED, Sridharan et al. 2002), the mass of gas and dust toward IRS 1 results in 0.3-0.6 M. ...
... Weak continuum emission at 230 GHz (at a 6 level) is found associated with IRS 1 with a flux density of 18.3 mJy. For a dust temperature between 20 K (from NH3 Miralles et al. 1994) and 44 K (derived from the SED, Sridharan et al. 2002), the mass of gas and dust toward IRS 1 results in 0.3-0.6 M. ...
Objective Classification of Galaxy Spectra using the Information Bottleneck Method
... characteristics of a galaxy are its mean stellar age and metallicity, or more generally its full star formation history. This is in turn presumably connected with morphological properties of the galaxy; eg. its Hubble or T-type. An assumed star formation history can be translated into a synthetic sp ...
... characteristics of a galaxy are its mean stellar age and metallicity, or more generally its full star formation history. This is in turn presumably connected with morphological properties of the galaxy; eg. its Hubble or T-type. An assumed star formation history can be translated into a synthetic sp ...
Classical Be Stars: Rapidly Rotating B Stars with Viscous Keplerian
... population with likely a different mechanism responsible for the filling of the circumstellar environment (which may nevertheless be disk-shaped). Star with Emission Line Magnetospheres: Magnetic B stars do not typically show line emission, but depending on the field strength, wind, mass-loss and ro ...
... population with likely a different mechanism responsible for the filling of the circumstellar environment (which may nevertheless be disk-shaped). Star with Emission Line Magnetospheres: Magnetic B stars do not typically show line emission, but depending on the field strength, wind, mass-loss and ro ...
Galactic Evolution of Silicon Isotopes: Application to Presolar SiC
... We have two motivations for studying the silicon isotopic abundance histories in the interstellar medium at distances and times appropriate to the birth of the solar system. Primarily we seek connections between evolution of the calculated silicon isotopic ratios and the anomalous silicon isotopic r ...
... We have two motivations for studying the silicon isotopic abundance histories in the interstellar medium at distances and times appropriate to the birth of the solar system. Primarily we seek connections between evolution of the calculated silicon isotopic ratios and the anomalous silicon isotopic r ...
to - NexStar Resource Site
... Although Galileo was the first to observe it with a telescope in 1610, Saturn has been known since prehistoric times. Up to 1977 Saturn was believed to be the only planet with a ring system. It was later discovered that all of the gas planets had ring systems, albeit faint, of their own. Saturn is a ...
... Although Galileo was the first to observe it with a telescope in 1610, Saturn has been known since prehistoric times. Up to 1977 Saturn was believed to be the only planet with a ring system. It was later discovered that all of the gas planets had ring systems, albeit faint, of their own. Saturn is a ...
Debris Disks: Seeing Dust, Thinking of Planetesimals and Planets
... Abstract Debris disks are optically thin, almost gas-free dusty disks observed around a significant fraction of main-sequence stars older than about 10 Myr. Since the circumstellar dust is short-lived, the very existence of these disks is considered as evidence that dust-producing planetesimals are ...
... Abstract Debris disks are optically thin, almost gas-free dusty disks observed around a significant fraction of main-sequence stars older than about 10 Myr. Since the circumstellar dust is short-lived, the very existence of these disks is considered as evidence that dust-producing planetesimals are ...
Equations of state and structure of neutron stars
... and are concentrated in two connected fields related to structure of the neutron (strange) stars and their external gravitational field. The first one is oriented on testing of equation of state for dense nuclear matter by astrophysical observations. We used set of parameterizations that has been fo ...
... and are concentrated in two connected fields related to structure of the neutron (strange) stars and their external gravitational field. The first one is oriented on testing of equation of state for dense nuclear matter by astrophysical observations. We used set of parameterizations that has been fo ...
Galactic Evolution of Silicon Isotopes: Applications to
... bulk ISM of Type II supernovae, Type Ia supernovae, and AGB stars ? (2) Are 29Si and 30Si primary or secondary nucleosynthesis products ? (3) In what isotopic direction in a three-isotope plot do corecollapse supernovae of di†erent mass move the silicon isotopic composition ? (4) Why do present calc ...
... bulk ISM of Type II supernovae, Type Ia supernovae, and AGB stars ? (2) Are 29Si and 30Si primary or secondary nucleosynthesis products ? (3) In what isotopic direction in a three-isotope plot do corecollapse supernovae of di†erent mass move the silicon isotopic composition ? (4) Why do present calc ...
A GMOS dissection of the line-of
... Absorber has metal-bearing gas, with column densities up to 1017 cm-2 in MgII. Where is the gas located? Could originate in outer halo of nearby galaxy. Nearest confirmed galaxy is 50kpc from line-of-sight, so quasar is likely to be still in the halo. ...
... Absorber has metal-bearing gas, with column densities up to 1017 cm-2 in MgII. Where is the gas located? Could originate in outer halo of nearby galaxy. Nearest confirmed galaxy is 50kpc from line-of-sight, so quasar is likely to be still in the halo. ...
Ultra-luminous Quasars with the Most Massive Black Holes at
... The first low-resolution optical spectrum of this source was obtained with the Lijiang 2.4 m telescope using the YFOSC on 2013 November 25 (UT), then follow-up by Magellan. ...
... The first low-resolution optical spectrum of this source was obtained with the Lijiang 2.4 m telescope using the YFOSC on 2013 November 25 (UT), then follow-up by Magellan. ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.