![Hot DQ White Dwarfs: Something Different](http://s1.studyres.com/store/data/017212575_1-86657b5394a7054d4d7bd9806c08401a-300x300.png)
Ptolemy: on trial for fraud
... lower limit did not arise in scholarly arguments position are too small by about 1°, but his latinever existed. Thus Ptolemy is not the greatest until much later (Goldstein 1982) and thus did tudes are basically correct. Precession – a slow astronomer of antiquity, but he is something not slow Dreye ...
... lower limit did not arise in scholarly arguments position are too small by about 1°, but his latinever existed. Thus Ptolemy is not the greatest until much later (Goldstein 1982) and thus did tudes are basically correct. Precession – a slow astronomer of antiquity, but he is something not slow Dreye ...
... Limitations of Hubble’s Law • Galaxies and other objects may have motions that have nothing to do with the expansion of space • When galaxies orbit each other, sometimes their orbital speed is much larger than the redshift caused by expansion. • We cannot use Hubble’s law for nearby galaxies, and c ...
Introduction: The History and Technique of Stellar Classification
... the old spectral types were consolidated together, and the types were re-arranged to reflect a steady change in the strengths of representative spectral lines. The order of the spectral classes became O, B, A, F, G, K, and M, and though the letter designations have no meaning other than that imposed ...
... the old spectral types were consolidated together, and the types were re-arranged to reflect a steady change in the strengths of representative spectral lines. The order of the spectral classes became O, B, A, F, G, K, and M, and though the letter designations have no meaning other than that imposed ...
PPT presentation
... luminosity functions, indistinguishable from those observed in the spiral galaxies M31 and M81. The invariance with galaxy type and metallicity demonstrated the PNLF to be an excellent standard candle. Model simulations indicated a central star mass distribution highly peaked at ~0.6 Msun, similar t ...
... luminosity functions, indistinguishable from those observed in the spiral galaxies M31 and M81. The invariance with galaxy type and metallicity demonstrated the PNLF to be an excellent standard candle. Model simulations indicated a central star mass distribution highly peaked at ~0.6 Msun, similar t ...
Classification of Variable Stars
... and Jaschek (Sterken and Jaschek 1996). As more classification schemes are proposed, each will be considered and integrated based on their merit. Two families of variable stars exist traditionally: intrinsic and extrinsic variable stars regardless of available classification scheme examined. The int ...
... and Jaschek (Sterken and Jaschek 1996). As more classification schemes are proposed, each will be considered and integrated based on their merit. Two families of variable stars exist traditionally: intrinsic and extrinsic variable stars regardless of available classification scheme examined. The int ...
Stellar astrophysics based on interferometry
... • Intensity profiles change with time (pulsation, variable features, etc.). • Distance is often not well known (absolute radii). ...
... • Intensity profiles change with time (pulsation, variable features, etc.). • Distance is often not well known (absolute radii). ...
Stars and Galaxies - Red Hook Central Schools
... http://hubblesite.org/newscenter/archive/releases/star/supernova/2004/09/results/50/ http://hubblesite.org/newscenter/archive/releases/nebula/supernova-remnant/2005/37/results/50/ http://chandra.harvard.edu/photo/2009/casa/ ...
... http://hubblesite.org/newscenter/archive/releases/star/supernova/2004/09/results/50/ http://hubblesite.org/newscenter/archive/releases/nebula/supernova-remnant/2005/37/results/50/ http://chandra.harvard.edu/photo/2009/casa/ ...
Chemical Evolution of Galactic Systems
... is whether pollution from intermediate-mass stellar winds is responsible for anomalous abundances in globular cluster stars. We test this scenario by modelling the formation and chemical evolution of a globular cluster. Recently, the most detailed abundance pattern ever measured beyond the local uni ...
... is whether pollution from intermediate-mass stellar winds is responsible for anomalous abundances in globular cluster stars. We test this scenario by modelling the formation and chemical evolution of a globular cluster. Recently, the most detailed abundance pattern ever measured beyond the local uni ...
CW9_MOST_GSphot_RK_v1
... “A BAD COMPARISON STAR” HD209775 is an F0 (V=7.59) field star close to (~1.2deg) the well known exo-planet transiting system HD209458 ...
... “A BAD COMPARISON STAR” HD209775 is an F0 (V=7.59) field star close to (~1.2deg) the well known exo-planet transiting system HD209458 ...
white dwarfs and the age of the universe
... the masses of the hydrogen layer are in the range between 10−8 and 10−4 M⊙ thus indicating that DAs are born with a variety of layer masses. As the DA star cools down, the convective region deepens and, depending on the mass, reaches the helium layer. When this happens, helium is dredged up and the ...
... the masses of the hydrogen layer are in the range between 10−8 and 10−4 M⊙ thus indicating that DAs are born with a variety of layer masses. As the DA star cools down, the convective region deepens and, depending on the mass, reaches the helium layer. When this happens, helium is dredged up and the ...
THE MONTHLY SKY GUIDE, SIXTH EDITION
... streak of light dash across the sky like a cosmic laser beam, lasting no more than a second or so. This is a meteor, popularly termed a shooting star. Do not misidentify shooting stars with satellites or high-flying aeroplanes, which look like moving stars but drift at a more leisurely pace. Despite ...
... streak of light dash across the sky like a cosmic laser beam, lasting no more than a second or so. This is a meteor, popularly termed a shooting star. Do not misidentify shooting stars with satellites or high-flying aeroplanes, which look like moving stars but drift at a more leisurely pace. Despite ...
PDF only - at www.arxiv.org.
... 2. Studying the dynamics of wide binary systems by means of using the available catalogues, parallaxes, and radial velocities. 3. Performing statistical work concerning with the systematic and accidental errors detected in visual double star observations, obtained by the Zeiss-60cm double refractor, ...
... 2. Studying the dynamics of wide binary systems by means of using the available catalogues, parallaxes, and radial velocities. 3. Performing statistical work concerning with the systematic and accidental errors detected in visual double star observations, obtained by the Zeiss-60cm double refractor, ...
Evolution of low mass stars
... The core of my Ph.D. project is building a new PARSEC database of α enhanced stellar evolutionary tracks and isochrones for Gaia. Precise studies on the Galactic bulge, globular cluster, Galactic halo and Galactic thick disk require stellar models with α enhancement and various helium contents. It i ...
... The core of my Ph.D. project is building a new PARSEC database of α enhanced stellar evolutionary tracks and isochrones for Gaia. Precise studies on the Galactic bulge, globular cluster, Galactic halo and Galactic thick disk require stellar models with α enhancement and various helium contents. It i ...
Penn State Astronomy 11 Laboratory
... You will have a planisphere, which can be purchased from the bookstore, to help you find stars and constellations. Most observations can be done during class time, weather permitting, but many must be done outside of class time. For out-of-class observations, you are encouraged to observe on your ow ...
... You will have a planisphere, which can be purchased from the bookstore, to help you find stars and constellations. Most observations can be done during class time, weather permitting, but many must be done outside of class time. For out-of-class observations, you are encouraged to observe on your ow ...
Chapter 2
... depend on the time or place where observations are made, they can be used to arrange the stars in order in catalogues. Catalogues are used by astronomers to find a particular star to observe. The fact that right ascension and declination don’t vary with time or place is an advantage in this case. It ...
... depend on the time or place where observations are made, they can be used to arrange the stars in order in catalogues. Catalogues are used by astronomers to find a particular star to observe. The fact that right ascension and declination don’t vary with time or place is an advantage in this case. It ...
High ions towards white dwarfs: circumstellar line shifts and stellar
... In principal, the three possible sources of absorption features in DA white dwarf UV spectra should be identifiable by an accurate measurement of their interstellar, photospheric and circumstellar velocities (Vism , Vphot and Vcirc ). This is especially true for nearby targets where the interstellar ...
... In principal, the three possible sources of absorption features in DA white dwarf UV spectra should be identifiable by an accurate measurement of their interstellar, photospheric and circumstellar velocities (Vism , Vphot and Vcirc ). This is especially true for nearby targets where the interstellar ...
Stellar kinematics
Stellar kinematics is the study of the movement of stars without needing to understand how they acquired their motion. This differs from stellar dynamics, which takes into account gravitational effects. The motion of a star relative to the Sun can provide useful information about the origin and age of a star, as well as the structure and evolution of the surrounding part of the Milky Way.In astronomy, it is widely accepted that most stars are born within molecular clouds known as stellar nurseries. The stars formed within such a cloud compose open clusters containing dozens to thousands of members. These clusters dissociate over time. Stars that separate themselves from the cluster's core are designated as members of the cluster's stellar association. If the remnant later drifts through the Milky Way as a coherent assemblage, then it is termed a moving group.