Spectroscopic Atlas for Amateur Astronomers
... Some spectral atlases were available in the past but are out of print today. The most comprehensive “reference work” is surely “Bonner Spektralatlas”, the title of the English edition: “Atlas for Objective Prism Spectra” by Waltraut C. Seitter, 1975 [5]). This atlas, covering the spectral types from ...
... Some spectral atlases were available in the past but are out of print today. The most comprehensive “reference work” is surely “Bonner Spektralatlas”, the title of the English edition: “Atlas for Objective Prism Spectra” by Waltraut C. Seitter, 1975 [5]). This atlas, covering the spectral types from ...
Stellarium User Guide
... scipting facility is Stellarium’s version of a “Presentation”, a feature that may be used to run an astronomical or other presentation for instruction or entertainment from within the Stellarium program. The original Stratoscript was quite limited in what it could do so a new Stellarium Scripting Sy ...
... scipting facility is Stellarium’s version of a “Presentation”, a feature that may be used to run an astronomical or other presentation for instruction or entertainment from within the Stellarium program. The original Stratoscript was quite limited in what it could do so a new Stellarium Scripting Sy ...
Planetary Nebula
... were shed by the central star after it ran out of fuel to sustain the nuclear reactions in its core. Planetary nebulae fade gradually over tens of thousands of years. The hot remnant stellar core of NGC 2818 will eventually cool off for billions of years as a white dwarf. NGC 2818, which lies in the ...
... were shed by the central star after it ran out of fuel to sustain the nuclear reactions in its core. Planetary nebulae fade gradually over tens of thousands of years. The hot remnant stellar core of NGC 2818 will eventually cool off for billions of years as a white dwarf. NGC 2818, which lies in the ...
Spitzer Spectroscopy of Circumstellar Disks in the 5 Myr Old Upper
... In a 4–16 µm Spitzer survey of 204 members of the Upper Scorpius OB association with masses ranging from ∼0.1 to 20 M⊙ , Carpenter et al. (2006) find only 35 stars with emission in excess of photospheric values at 8 or 16 µm. The low-mass (0.1–1.2 M⊙ ) stars are associated with excess emission that ...
... In a 4–16 µm Spitzer survey of 204 members of the Upper Scorpius OB association with masses ranging from ∼0.1 to 20 M⊙ , Carpenter et al. (2006) find only 35 stars with emission in excess of photospheric values at 8 or 16 µm. The low-mass (0.1–1.2 M⊙ ) stars are associated with excess emission that ...
Ages of young stars
... are combinations of theoretical uncertainties and observational uncertainties associated with estimating the luminosity of the LDB. Contributing to the latter are distance estimates, reddening and bolometric corrections (for stellar luminosity not in the band observed), but these are usually small c ...
... are combinations of theoretical uncertainties and observational uncertainties associated with estimating the luminosity of the LDB. Contributing to the latter are distance estimates, reddening and bolometric corrections (for stellar luminosity not in the band observed), but these are usually small c ...
exoplanet observing for amateurs
... The distinction is not related to the fact that professional astronomers understand everything in this book; it’s related to the fact that the professionals don’t need to know most of what’s in this book. Professionals don’t need to know how to deal with telescopes with an imperfect polar alignment ...
... The distinction is not related to the fact that professional astronomers understand everything in this book; it’s related to the fact that the professionals don’t need to know most of what’s in this book. Professionals don’t need to know how to deal with telescopes with an imperfect polar alignment ...
The Norma cluster (ACO3627) – II. The near-infrared Ks
... making optical observations particularly sensitive to galaxies where star formation is taking place, the NIR is much less affected by short bursts of star formation and therefore a better indicator of galaxy mass (Andreon & Pelló 2000). The NIR has the advantage of high resolution and sensitivity t ...
... making optical observations particularly sensitive to galaxies where star formation is taking place, the NIR is much less affected by short bursts of star formation and therefore a better indicator of galaxy mass (Andreon & Pelló 2000). The NIR has the advantage of high resolution and sensitivity t ...
Spectral Matching for Elemental Abundances of Evolved Stars of Globular Clusters
... used to estimate the oxygen abundance of the stars, leading to a determination of whether a particular star was oxygen-rich or oxygen-poor. From this a catalogue of abundances of iron, carbon and barium of 848 giant branch stars were determined, of which 557 also had well-defined nitrogen abundances ...
... used to estimate the oxygen abundance of the stars, leading to a determination of whether a particular star was oxygen-rich or oxygen-poor. From this a catalogue of abundances of iron, carbon and barium of 848 giant branch stars were determined, of which 557 also had well-defined nitrogen abundances ...
Hunting for Substructure in the Milky Way
... Type Ia supernovae are exploding white dwarf stars. A star exhibits a balance between the gravitational force causing it to collapse, and the pressure due to fusion and electron degeneracy, opposing the collapse. There is a critical mass above which the pressure can no longer significantly oppose th ...
... Type Ia supernovae are exploding white dwarf stars. A star exhibits a balance between the gravitational force causing it to collapse, and the pressure due to fusion and electron degeneracy, opposing the collapse. There is a critical mass above which the pressure can no longer significantly oppose th ...
Super-Eddington outburst in a binary system: V4641 Sgr Mikhail Revnivtsev, Marat Gilfanov
... M . Ratio of the accretion disk size to the companion star size is • Optical companion is large M > 3 − 5M . Ratio of the accretion large disk size to the companion star size • Surface temperature of the is not more than unity. companion star T < 5000K. temperature of the Much smaller than the surfa ...
... M . Ratio of the accretion disk size to the companion star size is • Optical companion is large M > 3 − 5M . Ratio of the accretion large disk size to the companion star size • Surface temperature of the is not more than unity. companion star T < 5000K. temperature of the Much smaller than the surfa ...
- National Optical Astronomy Observatory
... Movement of the Iron ions is restricted to the magnetic field lines from within the umbra to the edge of the penumbra. This is supported by the data, which shows an initial outward flow of the ions and then a downward flow near penumbra. Because the nickel particles are not ionized, their velocities ...
... Movement of the Iron ions is restricted to the magnetic field lines from within the umbra to the edge of the penumbra. This is supported by the data, which shows an initial outward flow of the ions and then a downward flow near penumbra. Because the nickel particles are not ionized, their velocities ...
Abd al-Rahman al-Sufi and his book of the fixed stars: a journey of
... important books in the history of Arabic and Islamic astronomy. This book was called Șuwar al-Kawākib al-Thamāniyah wa-al-Ārba'een, later known by its short name The Book of the Fixed Stars. It was written in Arabic by the famous Persian author and astronomer ′Abd alRaḥmān al-Ṣūfī around A.D. 964. E ...
... important books in the history of Arabic and Islamic astronomy. This book was called Șuwar al-Kawākib al-Thamāniyah wa-al-Ārba'een, later known by its short name The Book of the Fixed Stars. It was written in Arabic by the famous Persian author and astronomer ′Abd alRaḥmān al-Ṣūfī around A.D. 964. E ...