X-Ray Properties of Young Stars and Stellar Clusters
... explosive magnetic reconnection. The reconnection immediately accelerates a population of particles with energies tens of keV to several MeV; this is the “impulsive phase” manifested by gyrosynchrotron radio continuum emission, blue optical/UV continuum, and, in the Sun, high γ-ray and energetic par ...
... explosive magnetic reconnection. The reconnection immediately accelerates a population of particles with energies tens of keV to several MeV; this is the “impulsive phase” manifested by gyrosynchrotron radio continuum emission, blue optical/UV continuum, and, in the Sun, high γ-ray and energetic par ...
Document
... Since young, massive stars heat the dusty clouds from which they formed, resulting in the emission of much infrared radiation, the current rate of star formation in a galaxy can be estimated by measuring its infrared power. Space telescopes such as the Infrared Astronomical Satellite (IRAS, in the m ...
... Since young, massive stars heat the dusty clouds from which they formed, resulting in the emission of much infrared radiation, the current rate of star formation in a galaxy can be estimated by measuring its infrared power. Space telescopes such as the Infrared Astronomical Satellite (IRAS, in the m ...
bowser - Colorado Space Grant Consortium
... • Easy to maintain • May not be as stable of a • HST cost nearly 6 billion platform as HST ...
... • Easy to maintain • May not be as stable of a • HST cost nearly 6 billion platform as HST ...
Classification of Variable Stars
... exhausted. (i.e. V746 Oph is the 746th variable to be discovered in Ophiuchus.) Variable star names are determined by a committee appointed by the International Astronomical Union (I.A.U.). The assignments are made in the order in which the variable stars were discovered in a constellation. If one o ...
... exhausted. (i.e. V746 Oph is the 746th variable to be discovered in Ophiuchus.) Variable star names are determined by a committee appointed by the International Astronomical Union (I.A.U.). The assignments are made in the order in which the variable stars were discovered in a constellation. If one o ...
A trio of metalrich dust and gas discs found orbiting candidate white
... This paper reports follow-up photometric and spectroscopic observations, including warm Spitzer IRAC photometry of seven white dwarfs from the SDSS with apparent excess flux in UKIDSS K-band observations. Six of the science targets were selected from 16 785 DA star candidates identified either spect ...
... This paper reports follow-up photometric and spectroscopic observations, including warm Spitzer IRAC photometry of seven white dwarfs from the SDSS with apparent excess flux in UKIDSS K-band observations. Six of the science targets were selected from 16 785 DA star candidates identified either spect ...
starry night companion
... width of a finger at arm’s length is about 2°. The angular diameter of the moon is only 1/2°, although most people would guess it is much larger. Try it yourself. Block out the full moon with your little finger held at arm’s length. The field of view is an astronomical term which often confuses newc ...
... width of a finger at arm’s length is about 2°. The angular diameter of the moon is only 1/2°, although most people would guess it is much larger. Try it yourself. Block out the full moon with your little finger held at arm’s length. The field of view is an astronomical term which often confuses newc ...
Do We Know of Any Maunder Minimum Stars?
... those WMBV stars with more than two Keck observations are used in this work. The bulk of the ∼ 1000 stars in WMBV are currently being monitored for radial velocity variations and are typically bright, within two magnitudes of the main-sequence, and of spectral type F7 or later. The Mount Wilson proj ...
... those WMBV stars with more than two Keck observations are used in this work. The bulk of the ∼ 1000 stars in WMBV are currently being monitored for radial velocity variations and are typically bright, within two magnitudes of the main-sequence, and of spectral type F7 or later. The Mount Wilson proj ...
exploring anticorrelations and light element variations
... that the abundance inhomogeneities are of primordial origin. The most extensive spectroscopic survey of GCs undertaken so far (Carretta et al. 2009a, 2009b, 2009c) revealed that these inhomogeneities are ubiquitous in Galactic GCs, though they do not appear to occur in other star formation environme ...
... that the abundance inhomogeneities are of primordial origin. The most extensive spectroscopic survey of GCs undertaken so far (Carretta et al. 2009a, 2009b, 2009c) revealed that these inhomogeneities are ubiquitous in Galactic GCs, though they do not appear to occur in other star formation environme ...
PPT - ALFALFA survey
... Schneider (2000). It was a drift-scan survey taken in a series of declination strips with the Arecibo 305-m telescope. The velocity limit of the ADBS is 8000 km/s (it is volume limited!). The full ADBS sample includes 265 galaxies over ~420 sq. deg. • Since it is a “blind” HI survey, it does not suf ...
... Schneider (2000). It was a drift-scan survey taken in a series of declination strips with the Arecibo 305-m telescope. The velocity limit of the ADBS is 8000 km/s (it is volume limited!). The full ADBS sample includes 265 galaxies over ~420 sq. deg. • Since it is a “blind” HI survey, it does not suf ...
Star formation rates from young-star counts and the structure of the
... note that, given the steep dependence on SFR and the low number counts, distinguishing between a threshold and this power law is difficult and almost a matter of semantics. The work by Gutermuth et al. (2011) is the Galactic study that can be compared most directly to the NGC 346 analysis we prese ...
... note that, given the steep dependence on SFR and the low number counts, distinguishing between a threshold and this power law is difficult and almost a matter of semantics. The work by Gutermuth et al. (2011) is the Galactic study that can be compared most directly to the NGC 346 analysis we prese ...
5 Report of the Panel on Stars and Stellar Evolution
... How Do Rotation and Magnetic Fields Affect Stars? There’s an old chestnut about a dozing theorist at the weekly colloquium who opens his eyes at the end of every talk and rouses himself to ask, to great approbation for his subliminal understanding, “Yes, all very interesting, but what about rotatio ...
... How Do Rotation and Magnetic Fields Affect Stars? There’s an old chestnut about a dozing theorist at the weekly colloquium who opens his eyes at the end of every talk and rouses himself to ask, to great approbation for his subliminal understanding, “Yes, all very interesting, but what about rotatio ...
On the interpretation of stellar disc observations in terms of diameters
... this layer contribute only a small fraction of the observed intensity and observed flux. If the star were observed in different spectral features with successively increasing strength at about the same wavelength, an observer who cannot spatially resolve the disc and tries to interpret lunar-occulta ...
... this layer contribute only a small fraction of the observed intensity and observed flux. If the star were observed in different spectral features with successively increasing strength at about the same wavelength, an observer who cannot spatially resolve the disc and tries to interpret lunar-occulta ...
Stellar populations in the nuclear regions of nearby radio galaxies
... telescope is pointing. Since flat-fielding is crucial for the reddest wavelengths, where the sky lines are most prominent, after every exposure of 20–30 min we acquired a flat-field in the same position of the telescope as the one for which the galaxies were being observed. We followed this procedur ...
... telescope is pointing. Since flat-fielding is crucial for the reddest wavelengths, where the sky lines are most prominent, after every exposure of 20–30 min we acquired a flat-field in the same position of the telescope as the one for which the galaxies were being observed. We followed this procedur ...
Ferraro et al. 2006
... • Given its high luminosity (Mv=-9.4) and and half-mass radius (rh=25pc; Bellazzini 2007) NGC2419 lies (together with OmegaCen) Ripepi et al. 2007 in the (rh, MV )plane well above the locus defined by all the other Galactic GCs thus suggesting it might be the stripped core of a former dwarf galaxy ( ...
... • Given its high luminosity (Mv=-9.4) and and half-mass radius (rh=25pc; Bellazzini 2007) NGC2419 lies (together with OmegaCen) Ripepi et al. 2007 in the (rh, MV )plane well above the locus defined by all the other Galactic GCs thus suggesting it might be the stripped core of a former dwarf galaxy ( ...
Hipparcos distance estimates of the Ophiuchus and the Lupus cloud
... of star and planet formation in its entirety, and a deeper understanding of the effects of the local environment. A key aspect of the scientific analysis of a dark molecular cloud is its distance, which is related to many physically relevant properties (in particular, the mass scales as the square of ...
... of star and planet formation in its entirety, and a deeper understanding of the effects of the local environment. A key aspect of the scientific analysis of a dark molecular cloud is its distance, which is related to many physically relevant properties (in particular, the mass scales as the square of ...
Tycho Brahe
... star was not moving in relationship to other stars. • This observation challenged the beliefs of the time that the heavens remain unchanged. ...
... star was not moving in relationship to other stars. • This observation challenged the beliefs of the time that the heavens remain unchanged. ...
Abd al-Rahman al-Sufi and his book of the fixed stars: a journey of
... France in Paris, the British Library in London and the library of the American University of Beirut. Finally I would like to thank all people and especially my family for their help, support and patience during the time I spent working on this project. ...
... France in Paris, the British Library in London and the library of the American University of Beirut. Finally I would like to thank all people and especially my family for their help, support and patience during the time I spent working on this project. ...
PDF
... What can have happened to these star-forming peculiars so that they were so numerous 5 billion years ago but virtually absent by the present epoch? Two hypotheses are popular. The first suggests that the peculiars are transformed via mergers or by other means into regular ellipticals and spirals. Th ...
... What can have happened to these star-forming peculiars so that they were so numerous 5 billion years ago but virtually absent by the present epoch? Two hypotheses are popular. The first suggests that the peculiars are transformed via mergers or by other means into regular ellipticals and spirals. Th ...
Perseus (constellation)
Perseus, named after the Greek mythological hero Perseus, is a constellation in the northern sky. It was one of 48 listed by the 2nd-century astronomer Ptolemy and among the 88 modern constellations defined by the International Astronomical Union (IAU). It is located in the northern celestial hemisphere near several other constellations named after legends surrounding Perseus, including Andromeda to the west and Cassiopeia to the north. Perseus is also bordered by Aries and Taurus to the south, Auriga to the east, Camelopardalis to the north, and Triangulum to the west.The galactic plane of the Milky Way passes through Perseus but is mostly obscured by molecular clouds. The constellation's brightest star is the yellow-white supergiant Alpha Persei (also called Mirfak), which shines at magnitude 1.79. It and many of the surrounding stars are members of an open cluster known as the Alpha Persei Cluster. The best-known star, however, is Algol (Beta Persei), linked with ominous legends because of its variability, which is noticeable to the naked eye. Rather than being an intrinsically variable star, it is an eclipsing binary. Other notable star systems in Perseus include X Persei, a binary system containing a neutron star, and GK Persei, a nova that peaked at magnitude 0.2 in 1901. The Double Cluster, comprising two open clusters quite near each other in the sky, was known to the ancient Chinese. The constellation gives its name to the Perseus Cluster (Abell 426), a massive galaxy cluster located 250 million light-years from Earth. It hosts the radiant of the annual Perseids meteor shower—one of the most prominent meteor showers in the sky.