the Local Group - Simon P Driver
... velocities in a group • the mutual gravitaitonal pulls of the galaxies hold them together as a group – the group must have assembled fairly early on, or the expansion of the Universe would have spread galaxies out more evenly • several kinds of motions are possible – stable orbits around the gro ...
... velocities in a group • the mutual gravitaitonal pulls of the galaxies hold them together as a group – the group must have assembled fairly early on, or the expansion of the Universe would have spread galaxies out more evenly • several kinds of motions are possible – stable orbits around the gro ...
PH607lec08
... Triaxiality is also supported by observations of isophotal twists in some galaxies (would not see these if oblate or prolate) It was once thought that the shape of ellipticals varied from spherical to highly elongated. The Hubble classification of elliptical galaxies ranges from E0 for those that ar ...
... Triaxiality is also supported by observations of isophotal twists in some galaxies (would not see these if oblate or prolate) It was once thought that the shape of ellipticals varied from spherical to highly elongated. The Hubble classification of elliptical galaxies ranges from E0 for those that ar ...
148 Jun - British Astronomical Association
... cloud of dust and gas that partially obscures epsilon. Egress was interrupted by a denser part of the disk which may suggest a ring structure. Professionals involved in the international observing campaign have requested that observations (visual) and measurements (CCD / DSLR photometry) continue fo ...
... cloud of dust and gas that partially obscures epsilon. Egress was interrupted by a denser part of the disk which may suggest a ring structure. Professionals involved in the international observing campaign have requested that observations (visual) and measurements (CCD / DSLR photometry) continue fo ...
A Spitzer mid-infrared spectral survey of mass
... variability. Where further data are available, we list JHKL photometry averaged over the cycle in Table 2. Also listed are pulsation periods, taken from Whitelock et al. (2003), Wood (1998), Nishida et al. (2000), Ita et al. (2004) and Groenewegen (2004). Where available, periods from Whitelock et a ...
... variability. Where further data are available, we list JHKL photometry averaged over the cycle in Table 2. Also listed are pulsation periods, taken from Whitelock et al. (2003), Wood (1998), Nishida et al. (2000), Ita et al. (2004) and Groenewegen (2004). Where available, periods from Whitelock et a ...
A Variability Study of the Typical Red Supergiant Antares A
... the exception of the bright M-class supergiant Betelgeuse (α Orionis, M2 Iab). Betelgeuse has been well studied both observationally and theoretically, and has many features that are well described by models of convection. It was these studies of Betelgeuse that provided the main motivation for this ...
... the exception of the bright M-class supergiant Betelgeuse (α Orionis, M2 Iab). Betelgeuse has been well studied both observationally and theoretically, and has many features that are well described by models of convection. It was these studies of Betelgeuse that provided the main motivation for this ...
The Milky Way - The Independent School
... Several million, up to more than a billion solar masses! Supermassive ...
... Several million, up to more than a billion solar masses! Supermassive ...
docx file
... APOD: 2009 December 16 - Comet Hyakutake Passes the Earth Explanation: In 1996, an unexpectedly bright comet passed by planet Earth. Discovered less than two months before, Comet C/1996 B2 Hyakutake came within only 1/10th of the Earth-Sun distance from the Earth in late March. At that time, Comet H ...
... APOD: 2009 December 16 - Comet Hyakutake Passes the Earth Explanation: In 1996, an unexpectedly bright comet passed by planet Earth. Discovered less than two months before, Comet C/1996 B2 Hyakutake came within only 1/10th of the Earth-Sun distance from the Earth in late March. At that time, Comet H ...
Ages of Young Stars
... These results show that LDB age uncertainties have yet to attain the floor set by levels of theoretical understanding. There is scope for improvement, particularly in defining the position of the LDB, photometric calibration of cool stars and better estimates of cluster distances. The LDB technique ...
... These results show that LDB age uncertainties have yet to attain the floor set by levels of theoretical understanding. There is scope for improvement, particularly in defining the position of the LDB, photometric calibration of cool stars and better estimates of cluster distances. The LDB technique ...
365 days of SKYWATCHING
... Unlike a star chart, Moon feature instructions are based on lunar topography and not our Earthly cardinal directions. While these pages outline what features should be visible on any given night, the position of the terminator may be slightly different for viewers in various time zones. Let’s start ...
... Unlike a star chart, Moon feature instructions are based on lunar topography and not our Earthly cardinal directions. While these pages outline what features should be visible on any given night, the position of the terminator may be slightly different for viewers in various time zones. Let’s start ...
Planetary Nebula
... It’s the dim star, not the bright one, near the center of NGC 3132 that created this odd but beautiful planetary nebula. The pool of light seen surrounding this binary system is energized by the hot surface of the faint star. Blue represents the hottest gas, which is confined to the inner region of ...
... It’s the dim star, not the bright one, near the center of NGC 3132 that created this odd but beautiful planetary nebula. The pool of light seen surrounding this binary system is energized by the hot surface of the faint star. Blue represents the hottest gas, which is confined to the inner region of ...
Article PDF - IOPscience
... temperature regime where the physics of line broadening— van der Waals broadening in particular—becomes more questionable. The closest DB star with reliable atmospheric parameters lies at a distance of ∼30 pc. Finally, an initial sample of 169 white dwarf candidates has been retained for this analys ...
... temperature regime where the physics of line broadening— van der Waals broadening in particular—becomes more questionable. The closest DB star with reliable atmospheric parameters lies at a distance of ∼30 pc. Finally, an initial sample of 169 white dwarf candidates has been retained for this analys ...
Luminosities and mass-loss rates of SMC and LMC AGB stars and
... 86 M-stars. Tables 1 and 2 list basic information: some common names (as listed by SIMBAD), an OGLE-iii identifier when this lightcurve is analysed and shown in Fig. 3, R.A. and declination in decimal degrees, the identifier used in figures and tables below, the adopted pulsation period, the (semi-) ...
... 86 M-stars. Tables 1 and 2 list basic information: some common names (as listed by SIMBAD), an OGLE-iii identifier when this lightcurve is analysed and shown in Fig. 3, R.A. and declination in decimal degrees, the identifier used in figures and tables below, the adopted pulsation period, the (semi-) ...
1998 - Universitäts-Sternwarte München
... strictly differential with respect to the Sun. The modeling of the spectral lines is based on T. Gehren’s (1975) atmosphere program that makes use of the standard assumptions such as hydrostatic equilibrium, plane-parallel layers and local thermodynamic equilibrium, and is fed by the opacity distrib ...
... strictly differential with respect to the Sun. The modeling of the spectral lines is based on T. Gehren’s (1975) atmosphere program that makes use of the standard assumptions such as hydrostatic equilibrium, plane-parallel layers and local thermodynamic equilibrium, and is fed by the opacity distrib ...
ancient cultures 114 - Stellenbosch University
... true astronomical terms, however, a star is a giant ball of gas, constantly undergoing nuclear processes, and as such constantly emitting electromagnetic waves. The light waves produced from these reactions are particularly intense, such that the object can be seen from extremely far away. Our Sun i ...
... true astronomical terms, however, a star is a giant ball of gas, constantly undergoing nuclear processes, and as such constantly emitting electromagnetic waves. The light waves produced from these reactions are particularly intense, such that the object can be seen from extremely far away. Our Sun i ...
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 ...
A catalogue of the Chandra Deep Field South with multi
... MIDAS package. A WFI image processing pipeline was developed by Wolf et al. (2001) and makes intensive use of programmes developed by K. Meisenheimer, H.-J. Röser and H. Hippelein for the Calar Alto Deep Imaging Survey (CADIS). The pipeline performes basic image reduction and standard operations of ...
... MIDAS package. A WFI image processing pipeline was developed by Wolf et al. (2001) and makes intensive use of programmes developed by K. Meisenheimer, H.-J. Röser and H. Hippelein for the Calar Alto Deep Imaging Survey (CADIS). The pipeline performes basic image reduction and standard operations of ...
Statistical properties of a sample of periodically variable B-type supergiants ⋆
... He I 4471 line. Besides these, we observed one silicon line for each star with the goal to obtain an accurate temperature estimate. Depending on spectral type, this is either the Si II 4130 doublet (late B-type) or the Si III 4560 triplet (early B-type). The spectra were reduced in the standard way, ...
... He I 4471 line. Besides these, we observed one silicon line for each star with the goal to obtain an accurate temperature estimate. Depending on spectral type, this is either the Si II 4130 doublet (late B-type) or the Si III 4560 triplet (early B-type). The spectra were reduced in the standard way, ...
Chemical composition of 90 F and G disk dwarfs
... The parallax is taken from the Hipparcos Satellite observations (ESA 1997). For most program stars, the relative error in the parallax is of the order of 5%. Only two stars in our sample have errors larger than 10%. From these accurate parallaxes, stellar distances and absolute magnitudes were obtai ...
... The parallax is taken from the Hipparcos Satellite observations (ESA 1997). For most program stars, the relative error in the parallax is of the order of 5%. Only two stars in our sample have errors larger than 10%. From these accurate parallaxes, stellar distances and absolute magnitudes were obtai ...
Reassessing the formation of the inner Oort cloud
... which relied on extrasolar comets rather than indigenous comets to populate the Oort cloud, all of the above works suffer from the limitation that the stars are treated as hyperbolic encounters and the Sun is on a fixed orbit in the cluster. Both of these assumptions are wrong: the stars’ motion wi ...
... which relied on extrasolar comets rather than indigenous comets to populate the Oort cloud, all of the above works suffer from the limitation that the stars are treated as hyperbolic encounters and the Sun is on a fixed orbit in the cluster. Both of these assumptions are wrong: the stars’ motion wi ...
Boötes
Boötes /boʊˈoʊtiːz/ is a constellation in the northern sky, located between 0° and +60° declination, and 13 and 16 hours of right ascension on the celestial sphere. The name comes from the Greek Βοώτης, Boōtēs, meaning herdsman or plowman (literally, ox-driver; from βοῦς bous “cow”). The ""ö"" in the name is a diaeresis, not an umlaut, meaning that each 'o' is to be pronounced separately.One of the 48 constellations described by the 2nd century astronomer Ptolemy, Boötes is now one of the 88 modern constellations. It contains the fourth brightest star in the night sky, the orange-hued Arcturus. Boötes is home to many other bright stars, including eight above the fourth magnitude and an additional 21 above the fifth magnitude, making a total of 29 stars easily visible to the naked eye.