Chapter 1 The Discovery of Open Clusters - Willmann-Bell
... Very faint nebulae Planetary nebulae Very large nebulae Very compressed, rich clusters of stars Compressed clusters of small and large stars Coarsely scattered clusters of stars. Although now long superseded, the Herschel designations which resulted from this classification system proved sufficientl ...
... Very faint nebulae Planetary nebulae Very large nebulae Very compressed, rich clusters of stars Compressed clusters of small and large stars Coarsely scattered clusters of stars. Although now long superseded, the Herschel designations which resulted from this classification system proved sufficientl ...
Scientific Evidence for A
... Nucleon, it is impossible to make elements above Iron by simple Neutron capture and Beta decay! The only way to produce elements heavier than Iron is by neutron capture on a fast time scale before any of the short lived intermediaries can decay. This must occur during a super Novae explosion, where ...
... Nucleon, it is impossible to make elements above Iron by simple Neutron capture and Beta decay! The only way to produce elements heavier than Iron is by neutron capture on a fast time scale before any of the short lived intermediaries can decay. This must occur during a super Novae explosion, where ...
Astronomy Astrophysics First detection of the field star overdensity in the Perseus... &
... we use intermediate young stars with effective temperatures in the range [15 000, 9000] K (B4–A1 spectral type). These stars are excellent tracers of this overdensity as 1) they are bright enough to reach large distances from the Sun; and 2) they are old enough to have had time to respond to the spir ...
... we use intermediate young stars with effective temperatures in the range [15 000, 9000] K (B4–A1 spectral type). These stars are excellent tracers of this overdensity as 1) they are bright enough to reach large distances from the Sun; and 2) they are old enough to have had time to respond to the spir ...
The Norma cluster (ACO3627) – II. The near-infrared Ks
... Not all clusters can be modelled by a Schechter function, however. The Virgo cluster, for example, has a LF with a ‘double-wave’ structure (Binggeli et al. 1988). Clusters containing cD galaxies seem to have a steeper bright end than those without cD galaxies. Often the brightest galaxy is excluded ...
... Not all clusters can be modelled by a Schechter function, however. The Virgo cluster, for example, has a LF with a ‘double-wave’ structure (Binggeli et al. 1988). Clusters containing cD galaxies seem to have a steeper bright end than those without cD galaxies. Often the brightest galaxy is excluded ...
Celestial Navigation Second Edition
... learning process is exactly that. Leaning the pitfalls of possible mistakes and how to avoid them. This course offers so many practice examples, that you will have this under control before you set off. It is obviously much better to make all the mistakes on land, and save your time at sea for other ...
... learning process is exactly that. Leaning the pitfalls of possible mistakes and how to avoid them. This course offers so many practice examples, that you will have this under control before you set off. It is obviously much better to make all the mistakes on land, and save your time at sea for other ...
Spectroscopy-Heidelberg
... For low orders m (low spectral resolution, large free spectral range) one can use a filter that blocks light from the other orders For high orders m (the free spectral range is very small), use “cross disperser”: a second dispersive element (usually a prism), mounted with the dispersion direction pe ...
... For low orders m (low spectral resolution, large free spectral range) one can use a filter that blocks light from the other orders For high orders m (the free spectral range is very small), use “cross disperser”: a second dispersive element (usually a prism), mounted with the dispersion direction pe ...
the iconography of ancient astronomy
... can’t make an omelette without breaking an egg!). In Avestan mythology Orion and his dog Sirius/Tishtrya are central, and its tradition is implicit in Mithraic iconography. But for the sake of its new adherents in the Roman world, such imagery from Persia had to be spelled out explicitly, reinstatin ...
... can’t make an omelette without breaking an egg!). In Avestan mythology Orion and his dog Sirius/Tishtrya are central, and its tradition is implicit in Mithraic iconography. But for the sake of its new adherents in the Roman world, such imagery from Persia had to be spelled out explicitly, reinstatin ...
Folie 1
... How to answer some of these? Monitor the brightness of many YSOs over a long period of time. ...
... How to answer some of these? Monitor the brightness of many YSOs over a long period of time. ...
The physics of white dwarfs
... a result, detailed spectroscopic information has now been acquired for more than 400 of these stars. More recently, satellite and rocket-borne observations have begun to open up the far ultraviolet and x-ray regions of the spectrum that are inaccessible from ground-based observations, and important ...
... a result, detailed spectroscopic information has now been acquired for more than 400 of these stars. More recently, satellite and rocket-borne observations have begun to open up the far ultraviolet and x-ray regions of the spectrum that are inaccessible from ground-based observations, and important ...
Binary Star Formation Part 2
... Therefore stars must almost always be born in multiple systems and then multiplicity declines after ~300,000 years. ...
... Therefore stars must almost always be born in multiple systems and then multiplicity declines after ~300,000 years. ...
15.6 Planets Beyond the Solar System
... Jupiter-like planetary orbits have been found Recently, more Jupiter-like orbits have been found; this one has twice the mass of Jupiter and an orbital period of 6 years. You can see why it has taken so long to discover planets in Jupiter-like orbits: You have to observe for at least one orbital pe ...
... Jupiter-like planetary orbits have been found Recently, more Jupiter-like orbits have been found; this one has twice the mass of Jupiter and an orbital period of 6 years. You can see why it has taken so long to discover planets in Jupiter-like orbits: You have to observe for at least one orbital pe ...
April 2015 Astronomy Calendar by Dave Mitsky
... Mercury reaches superior conjunction on April 10th and disappears from view for most of the month. It reaches perihelion on April 19th. Brilliant Venus is positioned high in the west at sunset. It sets about three hours after the Sun in early April and three-and-one-half hours after sunset by month’ ...
... Mercury reaches superior conjunction on April 10th and disappears from view for most of the month. It reaches perihelion on April 19th. Brilliant Venus is positioned high in the west at sunset. It sets about three hours after the Sun in early April and three-and-one-half hours after sunset by month’ ...
The Marine Sextant
... Use of the Sextant • A sextant is used to determine the sextant altitude (hs) of a celestial body. • First, we have to decide which stars to observe; this is done using a Rude Starfinder or other methods. • When making an observation, the star should look as shown in the next slide... ...
... Use of the Sextant • A sextant is used to determine the sextant altitude (hs) of a celestial body. • First, we have to decide which stars to observe; this is done using a Rude Starfinder or other methods. • When making an observation, the star should look as shown in the next slide... ...
Article PDF - IOPscience
... three early-type stars in the Bridge between the LMC and the SMC with those observed in ““ normal ÏÏ B-type stars near the Sun. They found an average metal deÐciency [m/H] \ [1.05 ^ 0.12 for these objects. Surprisingly, this value falls well below the present (Luck et al. 1998) SMC metallicity [Fe/H ...
... three early-type stars in the Bridge between the LMC and the SMC with those observed in ““ normal ÏÏ B-type stars near the Sun. They found an average metal deÐciency [m/H] \ [1.05 ^ 0.12 for these objects. Surprisingly, this value falls well below the present (Luck et al. 1998) SMC metallicity [Fe/H ...
Historical astronomy How Johannes Kepler Johannes
... embarked on his lifelong quest for harmony. In a flight of mathematical mysticism, he tried to link the known planets to Plato’s five geometrical solids (the cube, tetrahedron, octahedron, icosahedron, and dodecahedron). By nesting each geometrical solid between the orbits of the planets, he thought ...
... embarked on his lifelong quest for harmony. In a flight of mathematical mysticism, he tried to link the known planets to Plato’s five geometrical solids (the cube, tetrahedron, octahedron, icosahedron, and dodecahedron). By nesting each geometrical solid between the orbits of the planets, he thought ...
The GL 569 Multiple System
... 9.81 ± 0.16 pc, and GL 569 B, thought to be a binary brown dwarf with period ∼ 876 days (Zapatero Osorio et al. 2004). We began a study of GL 569 B in 2002 because the astrometric orbit is well determined and the components, Ba and Bb, are bright enough to be observed at high spectral resolution in ...
... 9.81 ± 0.16 pc, and GL 569 B, thought to be a binary brown dwarf with period ∼ 876 days (Zapatero Osorio et al. 2004). We began a study of GL 569 B in 2002 because the astrometric orbit is well determined and the components, Ba and Bb, are bright enough to be observed at high spectral resolution in ...
Image filtering
... Sky noise-limited: all pixels have equal variance. The flux measurement of the fitted profile is equivalent to a profile-weighted aperture photometry Star photon noise-limited: variance is proportional to the pixel values above the background level. The flux measurement of the fitted profile is ...
... Sky noise-limited: all pixels have equal variance. The flux measurement of the fitted profile is equivalent to a profile-weighted aperture photometry Star photon noise-limited: variance is proportional to the pixel values above the background level. The flux measurement of the fitted profile is ...
The motions of the Earth
... • This scale was reversed: Magnitude 1 corresponded to the brightest stars; Magnitude 6 corresponded to the faintest stars visible with naked eyes. • This scale was logarithmic: stars of magnitude “n” were “seen” twice as bright as stars of magnitude “n+1”. • In 1856, Norman Robert Pogson proposed a ...
... • This scale was reversed: Magnitude 1 corresponded to the brightest stars; Magnitude 6 corresponded to the faintest stars visible with naked eyes. • This scale was logarithmic: stars of magnitude “n” were “seen” twice as bright as stars of magnitude “n+1”. • In 1856, Norman Robert Pogson proposed a ...
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... production mechanism. Our findings for R Hya and V441 Cyg have some important consequences for these intriguing objects. It was speculated that the declining pulsation period of R Hya is caused by a recent thermal pulse (TP). While not detecting Tc does not rule out a TP, it indicates that the TPs a ...
... production mechanism. Our findings for R Hya and V441 Cyg have some important consequences for these intriguing objects. It was speculated that the declining pulsation period of R Hya is caused by a recent thermal pulse (TP). While not detecting Tc does not rule out a TP, it indicates that the TPs a ...
Note - HKU Physics
... within a space of radius of the order of 100 light years. Thus, we can safely assume that stars in a single star cluster are formed from roughly the same material at about the same time under roughly the same physical conditions. Thus, mass of a star is perhaps the most important parameter to determ ...
... within a space of radius of the order of 100 light years. Thus, we can safely assume that stars in a single star cluster are formed from roughly the same material at about the same time under roughly the same physical conditions. Thus, mass of a star is perhaps the most important parameter to determ ...
The old globular cluster system of the dIrr galaxy NGC 1427A in the
... In all these models, the GCSs of low-mass dwarf galaxies, the most numerous galaxy type in galaxy clusters (Sandage 2005, and references therein), are envisioned as the building blocks of the GCSs of the more massive galaxies. At present the role of the GCSs of dIrr galaxies in the frame of galaxy f ...
... In all these models, the GCSs of low-mass dwarf galaxies, the most numerous galaxy type in galaxy clusters (Sandage 2005, and references therein), are envisioned as the building blocks of the GCSs of the more massive galaxies. At present the role of the GCSs of dIrr galaxies in the frame of galaxy f ...
Corvus (constellation)
Corvus is a small constellation in the Southern Celestial Hemisphere. Its name comes from the Latin word ""raven"" or ""crow"". It includes only 11 stars with brighter than 4.02 magnitudes. One of the 48 constellations listed by the 2nd-century astronomer Ptolemy, it remains one of the 88 modern constellations. The four brightest stars, Gamma, Delta, Epsilon, and Beta Corvi from a distinctive quadrilateral in the night sky. The young star Eta Corvi has been found to have two debris disks.