Measuring the Distance to the Sun: Final Report
... Because of the difficulties of finding cooperative groups we tested the algorithms and the possibilities of our own equipment in close cooperation with the Astronomische Arbeitsgemeinschaft Osnabrück4 (the details of theses tests are described in the document FirstTests5 . Erwin Heiser took several CC ...
... Because of the difficulties of finding cooperative groups we tested the algorithms and the possibilities of our own equipment in close cooperation with the Astronomische Arbeitsgemeinschaft Osnabrück4 (the details of theses tests are described in the document FirstTests5 . Erwin Heiser took several CC ...
1. Seyfert Galaxies
... Even hot stars cannot ionize gas as highly as these ions require, so that both a strong source of hard radiation and a wide range in gas density must be present to see such spectra. ...
... Even hot stars cannot ionize gas as highly as these ions require, so that both a strong source of hard radiation and a wide range in gas density must be present to see such spectra. ...
Hubble Space Telescope Imaging of Post
... and/or supernova feedback. Observationally, post-starburst galaxies have been linked to mergers and AGN (e.g., Brown et al. 2009; Falkenberg et al. 2009; Wild et al. 2009, and references therein). The environments and morphologies of post-starburst galaxies are heterogeneous, which is suggestive of ...
... and/or supernova feedback. Observationally, post-starburst galaxies have been linked to mergers and AGN (e.g., Brown et al. 2009; Falkenberg et al. 2009; Wild et al. 2009, and references therein). The environments and morphologies of post-starburst galaxies are heterogeneous, which is suggestive of ...
distribution and properties of a sample of massive young stars
... Before we can determine each source’s luminosity and thus, confirm the presence of a massive young star, we need to estimate its heliocentric distance. Kinematic distances can be derived using the source velocities in conjunction with a Galactic rotation model (e.g. Clemens 1985; Alvarez, May & Bron ...
... Before we can determine each source’s luminosity and thus, confirm the presence of a massive young star, we need to estimate its heliocentric distance. Kinematic distances can be derived using the source velocities in conjunction with a Galactic rotation model (e.g. Clemens 1985; Alvarez, May & Bron ...
Plotting the Rotation Curve of M31
... In this activity students use real data, taken from a scientific paper, to plot the rotational curve of M31 (Andromeda), our neighbouring spiral galaxy. They will look at Kepler’s third law to predict the motion of stars around the centre of M31. They will then measure the wavelengths of hydrogen emi ...
... In this activity students use real data, taken from a scientific paper, to plot the rotational curve of M31 (Andromeda), our neighbouring spiral galaxy. They will look at Kepler’s third law to predict the motion of stars around the centre of M31. They will then measure the wavelengths of hydrogen emi ...
Oxygen production on the AGB and the relevance of planetary
... • Figures includes oxygen isotope data from G-K giants, barium stars, MS, S and, C type AGB stars (Harris et al. 1984, 1987, 1988) • Predicted oxygen isotope ratios during the AGB are shown for two low-mass models; AGB evolution shows little shift from FDU values (Karakas et al. 2010) ...
... • Figures includes oxygen isotope data from G-K giants, barium stars, MS, S and, C type AGB stars (Harris et al. 1984, 1987, 1988) • Predicted oxygen isotope ratios during the AGB are shown for two low-mass models; AGB evolution shows little shift from FDU values (Karakas et al. 2010) ...
A CCD Search for Variable Stars of Spectral Type B in the Northern
... the strength of these results, Hill (1967) classified the star as a β Cep variable. However, Delgado et al. (1992), from 42 uvby observations obtained on two nights, concluded that NGC 2169-2 was constant in light. Our 3270 differential V magnitudes of NGC 2169-2, computed with NGC 216911 and 15 as ...
... the strength of these results, Hill (1967) classified the star as a β Cep variable. However, Delgado et al. (1992), from 42 uvby observations obtained on two nights, concluded that NGC 2169-2 was constant in light. Our 3270 differential V magnitudes of NGC 2169-2, computed with NGC 216911 and 15 as ...
Pulsating Stars: Stars that Breathe
... ’Breathing Stars’ In 1914, the American astronomer, Harlow Shapley, suggested that the observed variations in temperature and brightness of Cepheid variables were caused by radial pulsation. He argued that binary theories of stellar pulsation should be discarded and that astronomers should seek a me ...
... ’Breathing Stars’ In 1914, the American astronomer, Harlow Shapley, suggested that the observed variations in temperature and brightness of Cepheid variables were caused by radial pulsation. He argued that binary theories of stellar pulsation should be discarded and that astronomers should seek a me ...
The Formation and Evolution of the Milky Way
... Let’s consider the rate at which the elements are produced in the Galaxy The interstellar medium will be enriched faster in elements produced by shortlived stars (that is, the most massive ones) and more slowly in those elements produced essentially by type Ia supernovae and the low- and intermediat ...
... Let’s consider the rate at which the elements are produced in the Galaxy The interstellar medium will be enriched faster in elements produced by shortlived stars (that is, the most massive ones) and more slowly in those elements produced essentially by type Ia supernovae and the low- and intermediat ...
Read more - University of Central Lancashire
... the top, but near the wick at the bottom it is blue, that is because it is hotter at the bottom. The same idea applies to stars. The different colours tell us how hot the star is, the hottest stars are blue and white and the coolest are red. Is there a star called Bettlegaze? I think you mean a star ...
... the top, but near the wick at the bottom it is blue, that is because it is hotter at the bottom. The same idea applies to stars. The different colours tell us how hot the star is, the hottest stars are blue and white and the coolest are red. Is there a star called Bettlegaze? I think you mean a star ...
Morphology and Environment
... standards’ (Abraham et al. 1996). Instead of forcing distant galaxies into classification schemes based on nearby samples, it makes more sense to adopt a quantitative approach and define image parameters which may be used to classify these galaxies. Galaxies from the HST Medium Deep Survey have been ...
... standards’ (Abraham et al. 1996). Instead of forcing distant galaxies into classification schemes based on nearby samples, it makes more sense to adopt a quantitative approach and define image parameters which may be used to classify these galaxies. Galaxies from the HST Medium Deep Survey have been ...
Wandering in the Redshift Desert
... relief may be offered by Ly-α, if the specSQNFQ@OG HR DEjBHDMS DMNTFG HM SGD 45 Indeed, even if not in emission, Ly-α is such a strong feature that it helps a lot in getting redshifts. However, in a spectrograph such as e.g., VIMOS, Ly-α does not enter before z ~ 1.8, hence the range 1.4 < z < 1.8 i ...
... relief may be offered by Ly-α, if the specSQNFQ@OG HR DEjBHDMS DMNTFG HM SGD 45 Indeed, even if not in emission, Ly-α is such a strong feature that it helps a lot in getting redshifts. However, in a spectrograph such as e.g., VIMOS, Ly-α does not enter before z ~ 1.8, hence the range 1.4 < z < 1.8 i ...
Galaxy Evolution
... times brighter than stars like the Sun, their total luminosity will approximately equal that of 2 × 1010 of these. Thus, during the star formation activity the galaxy increases its luminosity by ∼ 20%. Its colors also become bluer, because the radiation emitted by massive stars is very rich of light ...
... times brighter than stars like the Sun, their total luminosity will approximately equal that of 2 × 1010 of these. Thus, during the star formation activity the galaxy increases its luminosity by ∼ 20%. Its colors also become bluer, because the radiation emitted by massive stars is very rich of light ...
A trip to the end of the universe and the twin “paradox”
... interesting information that both twins can interchange in our example are their individual proper times. They will not be able to determine the time dilation from this proper time because the information carrying the proper time of the other twin needs some time to travel the distance between them. ...
... interesting information that both twins can interchange in our example are their individual proper times. They will not be able to determine the time dilation from this proper time because the information carrying the proper time of the other twin needs some time to travel the distance between them. ...
CENTRAL TEXAS COLLEGE
... provide a sense of the mystery and majesty of the universe. As with our ancestors back beyond recorded time, we can’t help but wonder what kind of Universe is this? What are its fundamental laws? How old is it? How big? What does it contain? How has it changed with time, and what may be its future? ...
... provide a sense of the mystery and majesty of the universe. As with our ancestors back beyond recorded time, we can’t help but wonder what kind of Universe is this? What are its fundamental laws? How old is it? How big? What does it contain? How has it changed with time, and what may be its future? ...
History of IGM (C. Carilli)
... White etal (2002): ‘superluminal’ ionization front Stromgren sphere expands at close to speed of light => obs Ly a photons emitted just after ionizing photons “Delay required to allow light to travel from source to the edge of the sphere is exactly compensated by the ‘speedup’ that results from ...
... White etal (2002): ‘superluminal’ ionization front Stromgren sphere expands at close to speed of light => obs Ly a photons emitted just after ionizing photons “Delay required to allow light to travel from source to the edge of the sphere is exactly compensated by the ‘speedup’ that results from ...
Galaxy Evolution Encyclopedia of Astronomy & Astrophysics eaa.iop.org Mauro Giavalisco
... times brighter than stars like the Sun, their total luminosity will approximately equal that of 2 × 1010 of these. Thus, during the star formation activity the galaxy increases its luminosity by ∼ 20%. Its colors also become bluer, because the radiation emitted by massive stars is very rich of light ...
... times brighter than stars like the Sun, their total luminosity will approximately equal that of 2 × 1010 of these. Thus, during the star formation activity the galaxy increases its luminosity by ∼ 20%. Its colors also become bluer, because the radiation emitted by massive stars is very rich of light ...
Stars
... Magnitude • The classification of stars by absolute magnitude allows comparisons that are based on how bright the stars would appear at equal distances from an observer. The disadvantage of absolute magnitude is that it can be difficult to determine unless the actual distance to a star is known. ...
... Magnitude • The classification of stars by absolute magnitude allows comparisons that are based on how bright the stars would appear at equal distances from an observer. The disadvantage of absolute magnitude is that it can be difficult to determine unless the actual distance to a star is known. ...
radial metallicity gradients and age-metallicity relation of stars in the
... 0.45 +0.5E(B−V); if there were not enough targets, the red edge was extended2. With these criteria, we are predominantly selecting FG stars with magnitudes down to V = 16.5 (Gilmore et al., in prep.). The stellar parameters, T eff , log g, [Fe/H], and abundances for the UVES spectra are determined as ...
... 0.45 +0.5E(B−V); if there were not enough targets, the red edge was extended2. With these criteria, we are predominantly selecting FG stars with magnitudes down to V = 16.5 (Gilmore et al., in prep.). The stellar parameters, T eff , log g, [Fe/H], and abundances for the UVES spectra are determined as ...
Introduction: The History and Technique of Stellar Classification
... ESC 115 Lab 7, Techniques of Stellar Astronomy 3000 K, since molecules are broken apart (dissociated) at high temperatures. Stars with strong hydrogen lines, the A stars, had intermediate temperatures (around 10,000 K). The decimal divisions of spectral types followed the same pattern. Thus a B5 st ...
... ESC 115 Lab 7, Techniques of Stellar Astronomy 3000 K, since molecules are broken apart (dissociated) at high temperatures. Stars with strong hydrogen lines, the A stars, had intermediate temperatures (around 10,000 K). The decimal divisions of spectral types followed the same pattern. Thus a B5 st ...
NASA FUSE Satellite Solves the Case of the Missing Deuterium
... computer models that showed how deuterium, compared to hydrogen, might preferentially bind to interstellar dust grains, changing from an easily detectable gaseous form to an unobservable solid form. The new FUSE data strongly support this theory. In regions that remain undisturbed for long periods, ...
... computer models that showed how deuterium, compared to hydrogen, might preferentially bind to interstellar dust grains, changing from an easily detectable gaseous form to an unobservable solid form. The new FUSE data strongly support this theory. In regions that remain undisturbed for long periods, ...
On the origin of stars with and without planets
... We explore a sample of 148 solar-like stars to search for a possible correlation between the slopes of the abundance trends versus condensation temperature (known as the T c slope) with stellar parameters and Galactic orbital parameters in order to understand the nature of the peculiar chemical sign ...
... We explore a sample of 148 solar-like stars to search for a possible correlation between the slopes of the abundance trends versus condensation temperature (known as the T c slope) with stellar parameters and Galactic orbital parameters in order to understand the nature of the peculiar chemical sign ...
Diapositiva 1 - Yale University
... What is an Astrometric Survey? An astrometric survey can be defined as a search oriented to finding those celestial objects meeting a given accuracy in their absolute or relative positions, motions or trigonometric distances. Some of these surveys have been conducted with ground-based meridian ...
... What is an Astrometric Survey? An astrometric survey can be defined as a search oriented to finding those celestial objects meeting a given accuracy in their absolute or relative positions, motions or trigonometric distances. Some of these surveys have been conducted with ground-based meridian ...
Hot subdwarf stars-galactic orbits and distribution perpendicular to
... We have investigated 41 stars for their kinematic behaviour. The choice of stars was solely determined by the availability of the parameters necessary to calculate orbits. The stars selected are listed in Table 1. The sample includes the stars already investigated by Colin et al. (1994). For 12 star ...
... We have investigated 41 stars for their kinematic behaviour. The choice of stars was solely determined by the availability of the parameters necessary to calculate orbits. The stars selected are listed in Table 1. The sample includes the stars already investigated by Colin et al. (1994). For 12 star ...
Discovery of radio afterglow from most distant cosmic explosion
... • We have detected the radio afterglow of GRB 090324 at z=8.3 • The best-fit broad-band afterglow model is a quasi-spherical (θj>12o), hyper-energetic (1052 erg) explosion in a constant, low density (n=1 cm-3) medium. • GRB 050904 (z=6.26) was also hyper-energetic but it exploded into a high density ...
... • We have detected the radio afterglow of GRB 090324 at z=8.3 • The best-fit broad-band afterglow model is a quasi-spherical (θj>12o), hyper-energetic (1052 erg) explosion in a constant, low density (n=1 cm-3) medium. • GRB 050904 (z=6.26) was also hyper-energetic but it exploded into a high density ...
Cosmic distance ladder
The cosmic distance ladder (also known as the extragalactic distance scale) is the succession of methods by which astronomers determine the distances to celestial objects. A real direct distance measurement of an astronomical object is possible only for those objects that are ""close enough"" (within about a thousand parsecs) to Earth. The techniques for determining distances to more distant objects are all based on various measured correlations between methods that work at close distances and methods that work at larger distances. Several methods rely on a standard candle, which is an astronomical object that has a known luminosity.The ladder analogy arises because no one technique can measure distances at all ranges encountered in astronomy. Instead, one method can be used to measure nearby distances, a second can be used to measure nearby to intermediate distances, and so on. Each rung of the ladder provides information that can be used to determine the distances at the next higher rung.