NAS biographical memoir of Martin Schwarzschild
... Schwarzschild’s style as a scientist combined traits rarely found together in a single individual: a broad and vigorous creativity that was based on a thorough understanding of physical principles; a passion for detailed and precise numerical work to determine the consequences of physical models; an ...
... Schwarzschild’s style as a scientist combined traits rarely found together in a single individual: a broad and vigorous creativity that was based on a thorough understanding of physical principles; a passion for detailed and precise numerical work to determine the consequences of physical models; an ...
RApid Temporal Survey-RATS I: Overview and first results
... between frames. For each chip we flat-fielded and bias subtracted each image. The analysis (for each chip) consisted of following steps: the first 5 frames of each field were combined in order to form a ‘master’ image of the field. This master image was then searched for all the sources above a 5σ d ...
... between frames. For each chip we flat-fielded and bias subtracted each image. The analysis (for each chip) consisted of following steps: the first 5 frames of each field were combined in order to form a ‘master’ image of the field. This master image was then searched for all the sources above a 5σ d ...
WGCP 5th Jan 16 Astrophotography by Steve Baldwin
... There is a significant list of subjects that fall under the umbrella of astrophotography, not all of them visible after dark: • Lunar images *#% • Starscapes (landscapes taken after dark) and star trails *#% • Milky Way *#% • Planetary conjunctions *#% • ISS and satellites *#% • Meteor showers *# • ...
... There is a significant list of subjects that fall under the umbrella of astrophotography, not all of them visible after dark: • Lunar images *#% • Starscapes (landscapes taken after dark) and star trails *#% • Milky Way *#% • Planetary conjunctions *#% • ISS and satellites *#% • Meteor showers *# • ...
The Milky Way as a galaxy
... (color-magnitude diagrams for some star clusters are displayed in Fig. 2.5); since they are all located at the same distance, their main sequence is already defined in a colormagnitude diagram in which only apparent magnitudes are plotted. This cluster main sequence can then be fitted to a calibrate ...
... (color-magnitude diagrams for some star clusters are displayed in Fig. 2.5); since they are all located at the same distance, their main sequence is already defined in a colormagnitude diagram in which only apparent magnitudes are plotted. This cluster main sequence can then be fitted to a calibrate ...
DUSTY CIRCUMSTELLAR DISKS B. Zuckerman
... of disks that orbit a few of the Vega-like stars (including Vega itself). These observations have been of thermal emission from grains at IR wavelengths between 10 and 25 µm, and, also, in the microwave band, near 1 mm wavelength. In addition, the NICMOS camera on the Hubble space telescope (HST) ha ...
... of disks that orbit a few of the Vega-like stars (including Vega itself). These observations have been of thermal emission from grains at IR wavelengths between 10 and 25 µm, and, also, in the microwave band, near 1 mm wavelength. In addition, the NICMOS camera on the Hubble space telescope (HST) ha ...
The Classification of Galaxies By Daniel Underwood Contents The
... nebulae outside the Milky Way we realised, and it became universally accepted by astronomers that there were other galaxies than our own in the cosmos. However, it wasn’t immediately recognised that these nebulae were actually galaxies like our own, it took time to realise that they weren’t gaseous, ...
... nebulae outside the Milky Way we realised, and it became universally accepted by astronomers that there were other galaxies than our own in the cosmos. However, it wasn’t immediately recognised that these nebulae were actually galaxies like our own, it took time to realise that they weren’t gaseous, ...
Nucleosynthesis and Chemical Evolution of Oxygen
... The model presented here is that of Meyer (2005) using the stellar evolution code of The et al. (2000) and El Eid et al. (2004) but with coupled nuclear burning and convection using routines written by Jordan et al. (2004). The star began with a mass 25 times greater than that of the Sun. By the end ...
... The model presented here is that of Meyer (2005) using the stellar evolution code of The et al. (2000) and El Eid et al. (2004) but with coupled nuclear burning and convection using routines written by Jordan et al. (2004). The star began with a mass 25 times greater than that of the Sun. By the end ...
astro-ph/0303282 PDF
... though the total dust mass is orders of magnitude higher than in our system. Recent sub-mm and mm imaging of these systems (Holland et al. 1998, Greaves et al. 1998, Koerner et al. 2002, Willner et al. 2002, Holland et al. 2002) resolves the circumstellar dust and reveals complex structures, often i ...
... though the total dust mass is orders of magnitude higher than in our system. Recent sub-mm and mm imaging of these systems (Holland et al. 1998, Greaves et al. 1998, Koerner et al. 2002, Willner et al. 2002, Holland et al. 2002) resolves the circumstellar dust and reveals complex structures, often i ...
PH607lec08
... • The dust lanes seen in E galaxies imply that the absorbing material is distributed in rings or disks. Dust lanes may be aligned with either the major or minor axes, or they may be warped. • E galaxies contain modest amounts of cool and warm gas, although not as much as is found in S galaxies. A fe ...
... • The dust lanes seen in E galaxies imply that the absorbing material is distributed in rings or disks. Dust lanes may be aligned with either the major or minor axes, or they may be warped. • E galaxies contain modest amounts of cool and warm gas, although not as much as is found in S galaxies. A fe ...
Astronomy Astrophysics
... Some stars deserve a more detailed discussion because the parameter determination was not straight forward. G 86 - B1B = WD 0518+333: Bergeron et al. (2001) mark this star as possible double degenerate. The atmospheric parameters derived from spectroscopy (Bergeron et al. 1995a) differ considerably f ...
... Some stars deserve a more detailed discussion because the parameter determination was not straight forward. G 86 - B1B = WD 0518+333: Bergeron et al. (2001) mark this star as possible double degenerate. The atmospheric parameters derived from spectroscopy (Bergeron et al. 1995a) differ considerably f ...
20_Testbank
... the Milky Way. Therefore, they serve as a bridge between us and standard candles in other galaxies. Once we determine the distance to another galaxy for which we have observed a whitedwarf supernova, we then can calibrate the average luminosity of white-dwarf supernovae. White-dwarf supernovae and C ...
... the Milky Way. Therefore, they serve as a bridge between us and standard candles in other galaxies. Once we determine the distance to another galaxy for which we have observed a whitedwarf supernova, we then can calibrate the average luminosity of white-dwarf supernovae. White-dwarf supernovae and C ...
hwd_ewd_v3 - X-ray and Observational Astronomy Group
... The basis for understanding the nature of most stars is analysis of their optical spectra and classification according to the characteristics revealed. A number of physical processes can alter the atmospheric composition of a white dwarf as it cools. As noted by Schatzman4, the strong gravitational ...
... The basis for understanding the nature of most stars is analysis of their optical spectra and classification according to the characteristics revealed. A number of physical processes can alter the atmospheric composition of a white dwarf as it cools. As noted by Schatzman4, the strong gravitational ...
PowerPoint Presentation - Isolated Neutron Stars, solid crust
... devoted to study the faint thermal emission from neutron stars and to search for features in their spectrum. Isolated neutron stars play a key role in compact objects astrophysics: these are the only sources in which we can see directly the surface of the compact star. ...
... devoted to study the faint thermal emission from neutron stars and to search for features in their spectrum. Isolated neutron stars play a key role in compact objects astrophysics: these are the only sources in which we can see directly the surface of the compact star. ...
Why is the Sun very dense on the inside?
... Why do the hottest spectra (types O and B) show few absorption lines? ...
... Why do the hottest spectra (types O and B) show few absorption lines? ...
Laboratory A
... 10. On the scale drawing of the NPOI site, 1 in is 140 ft. What is this in centimeters to meters? 2.54 cm to 42.672 m, or 1 cm to 16.8 m 11. On the scale drawing of the NPOI site, 1 in is 140 ft. What are the dimensions of the Beam Combing Building on the drawing in inches? length = 1,125/3,556 in, ...
... 10. On the scale drawing of the NPOI site, 1 in is 140 ft. What is this in centimeters to meters? 2.54 cm to 42.672 m, or 1 cm to 16.8 m 11. On the scale drawing of the NPOI site, 1 in is 140 ft. What are the dimensions of the Beam Combing Building on the drawing in inches? length = 1,125/3,556 in, ...
The empirical mass distribution of hot B subdwarfs
... single stars (11 stars) and sdBs residing in binary systems (11 stars) are very similar (see Table 1). This is an indication that the majority of sdB stars, including the isolated ones, are indeed post-red giant stars. Moreover, the empirical mass distribution strongly peaking at ∼0.47 M suggests t ...
... single stars (11 stars) and sdBs residing in binary systems (11 stars) are very similar (see Table 1). This is an indication that the majority of sdB stars, including the isolated ones, are indeed post-red giant stars. Moreover, the empirical mass distribution strongly peaking at ∼0.47 M suggests t ...
Galaxies - WordPress.com
... A an enormous luminous cloud of gas and dust in the interstellar space. B a collection of planets with a parent star similar to the solar system. C a collection of hundreds of billions of stars sometimes called a galaxy. D a figment of the imagination of early astronomers like, the "seas" of the moo ...
... A an enormous luminous cloud of gas and dust in the interstellar space. B a collection of planets with a parent star similar to the solar system. C a collection of hundreds of billions of stars sometimes called a galaxy. D a figment of the imagination of early astronomers like, the "seas" of the moo ...
The ages of pre-main-sequence stars
... low metallicity is also typical of star-forming regions in the Large Magellanic Cloud. We therefore discuss a set of low-metallicity tracks which demonstrate how both mass and age determinations from colour±magnitude diagrams depend critically on a knowledge of metallicity. Because the stellar mass ...
... low metallicity is also typical of star-forming regions in the Large Magellanic Cloud. We therefore discuss a set of low-metallicity tracks which demonstrate how both mass and age determinations from colour±magnitude diagrams depend critically on a knowledge of metallicity. Because the stellar mass ...
Lecture 16
... In 1962 Maarten Schmidt identified a “star” coincident with the radio source and obtained a spectrum. He discovered it was not a star, and named it a QUASAR. ...
... In 1962 Maarten Schmidt identified a “star” coincident with the radio source and obtained a spectrum. He discovered it was not a star, and named it a QUASAR. ...
Magnetic fields in O-, B- and A-type stars on the main sequence
... An explanation of the observed fields of Ap stars already proposed a long time ago is the fossil origin. The fossil origin suggests that magnetic fields reside inside the star without being continuously renewed. Therefore, these fields have been formed during an early phase of the life of the star. The ...
... An explanation of the observed fields of Ap stars already proposed a long time ago is the fossil origin. The fossil origin suggests that magnetic fields reside inside the star without being continuously renewed. Therefore, these fields have been formed during an early phase of the life of the star. The ...
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.