Elliptical galaxies
... Mg (by type II SNe, on short timescales), Fe (by type Ia SNe, on longer timescale), the Mg/Fe-mass relation implies that the more massive objects should have formed faster than the less massive ones Pipino & Matteucci (2004) implemented an infall term in the chemical evolution equation and found tha ...
... Mg (by type II SNe, on short timescales), Fe (by type Ia SNe, on longer timescale), the Mg/Fe-mass relation implies that the more massive objects should have formed faster than the less massive ones Pipino & Matteucci (2004) implemented an infall term in the chemical evolution equation and found tha ...
distribution and properties of a sample of massive young stars
... Source or RMS survey1 ) with the specific aim of identifying a large well-selected sample of massive young stellar objects (MYSOs). Observationally, an MYSO is defined as a stellar object which is mid-IR bright and processes sufficient luminosity to form a massive star (greater than a few times 103 ...
... Source or RMS survey1 ) with the specific aim of identifying a large well-selected sample of massive young stellar objects (MYSOs). Observationally, an MYSO is defined as a stellar object which is mid-IR bright and processes sufficient luminosity to form a massive star (greater than a few times 103 ...
Altair - the hottest `cool` star in X-rays
... 2.4 MK and its emission measure distribution (EMD) is dominated by rather cool plasma at temperatures in the range of 1 – 4 MK, additionally a weak hotter component seems to contribute at a few percent level. These properties are quite typical for weakly active stars and similar to those of the quie ...
... 2.4 MK and its emission measure distribution (EMD) is dominated by rather cool plasma at temperatures in the range of 1 – 4 MK, additionally a weak hotter component seems to contribute at a few percent level. These properties are quite typical for weakly active stars and similar to those of the quie ...
Is the central binary system of the planetary nebula Henize 2
... in Abell 48 whose central star is a WN star (Todt et al., 2013). Most interestingly, in the study by Weidmann and Gamen (2011) there are several PNe that show a wide He II 5412 Å absorption line with a weak emission feature in the center of the wide absorption line. This forms a spectral structure ...
... in Abell 48 whose central star is a WN star (Todt et al., 2013). Most interestingly, in the study by Weidmann and Gamen (2011) there are several PNe that show a wide He II 5412 Å absorption line with a weak emission feature in the center of the wide absorption line. This forms a spectral structure ...
Active Galactic Nuclei
... Quasars are observed only at high redshifts – at large lookback times, so they existed in the distant past. There are no nearby quasars. The lower luminosity AGN’s, the Seyfert and starburst galaxies, bridge the gap between us and the more distant quasars ...
... Quasars are observed only at high redshifts – at large lookback times, so they existed in the distant past. There are no nearby quasars. The lower luminosity AGN’s, the Seyfert and starburst galaxies, bridge the gap between us and the more distant quasars ...
IEEE 2 Column Format
... interstellar medium, (viii) age of a star, (ix) the effect of tidal forces of nearby stars, and (x) nucleus activities in interior of star. The variable candidates were identified by inspecting their light curves [1]. The identification of variable stars is a crucial task due to following reasons: ( ...
... interstellar medium, (viii) age of a star, (ix) the effect of tidal forces of nearby stars, and (x) nucleus activities in interior of star. The variable candidates were identified by inspecting their light curves [1]. The identification of variable stars is a crucial task due to following reasons: ( ...
Introduction to Basic Stargazing Part I - Naples Free-Net
... This brings up an important point. Wherever spot you choose to star gaze needs to be dark, as dark a place as you can find. Not just on the ground like inside the shadow of a building, but the sky needs to be dark too. So dark, that a passing cloud looks like a black hole in the sky. Those places a ...
... This brings up an important point. Wherever spot you choose to star gaze needs to be dark, as dark a place as you can find. Not just on the ground like inside the shadow of a building, but the sky needs to be dark too. So dark, that a passing cloud looks like a black hole in the sky. Those places a ...
Universe 8e Lecture Chapter 24 Galaxies
... Hot intergalactic gases in rich clusters account for a small part of the unobserved mass. These gases are detected by their X-ray emission. The remaining unobserved mass is probably in the form of dark-matter halos that surround the galaxies in these clusters. Gravitational lensing of remote galaxie ...
... Hot intergalactic gases in rich clusters account for a small part of the unobserved mass. These gases are detected by their X-ray emission. The remaining unobserved mass is probably in the form of dark-matter halos that surround the galaxies in these clusters. Gravitational lensing of remote galaxie ...
Absorption efficiencies of antenna complexes in photosynthetic
... signal of vegetation on exoplanets, it will be a direct evidence of a trace of life. However, a trace of the vegetation on the exoplanets is uncertain, when the primal star is different from the Sun. As the first step before detecting the trace of the vegetation on the planets, it should be examined ...
... signal of vegetation on exoplanets, it will be a direct evidence of a trace of life. However, a trace of the vegetation on the exoplanets is uncertain, when the primal star is different from the Sun. As the first step before detecting the trace of the vegetation on the planets, it should be examined ...
129 DYNAMICAL STREAMS IN THE SOLAR NEIGHBOURHOOD B
... alone is not sufficient to create the observed streams. Nevertheless, De Simone et al. (2004) have shown that the structure of the local distribution function could well be due to a lumpy potential related to the presence of strong transient spiral waves. Besides those simulations, a recent model of ...
... alone is not sufficient to create the observed streams. Nevertheless, De Simone et al. (2004) have shown that the structure of the local distribution function could well be due to a lumpy potential related to the presence of strong transient spiral waves. Besides those simulations, a recent model of ...
NRO M33 All Disk Survey of Giant Molecular Clouds (NRO MAGiC
... The interstellar medium (ISM) is one of the essential components of galaxies because stars are born in and return to them. The ISM is greatly influenced by massive stars due to their stellar winds and supernova after their death. Therefore, the formation process of massive stars within the ISM is cru ...
... The interstellar medium (ISM) is one of the essential components of galaxies because stars are born in and return to them. The ISM is greatly influenced by massive stars due to their stellar winds and supernova after their death. Therefore, the formation process of massive stars within the ISM is cru ...
Activity 1: The Scientific Method
... 1) Start by becoming aware of your own biases. Do you believe any of the data is correlated? If so how? Relationship Example: radial motion of the stars and temperature Should state relationships that you believe might exist ...
... 1) Start by becoming aware of your own biases. Do you believe any of the data is correlated? If so how? Relationship Example: radial motion of the stars and temperature Should state relationships that you believe might exist ...
19_Testbank - Lick Observatory
... Answer: A star made of only helium and hydrogen would have to be among the first generation of stars ever born, arising out of the primordial mix of elements that came from the Big Bang. The oldest stars we know about are over 12-15 billion years old—a star made of only helium and hydrogen would hav ...
... Answer: A star made of only helium and hydrogen would have to be among the first generation of stars ever born, arising out of the primordial mix of elements that came from the Big Bang. The oldest stars we know about are over 12-15 billion years old—a star made of only helium and hydrogen would hav ...
white dwarfs.
... in the Big Bang. by nucleosynthesis in massive stars. in the cores of stars like the Sun. within planetary nebula. They have always existed. ...
... in the Big Bang. by nucleosynthesis in massive stars. in the cores of stars like the Sun. within planetary nebula. They have always existed. ...
Learning About Stars
... How to Find Polaris First, you need to find the Big Dipper. The Big Dipper is not a constellation itself. It is an asterism. An asterism is a group of stars that are part of another constellation. The Big Dipper is part of Ursa Major (the Great Bear). It is fairly easy to find in the sky. ...
... How to Find Polaris First, you need to find the Big Dipper. The Big Dipper is not a constellation itself. It is an asterism. An asterism is a group of stars that are part of another constellation. The Big Dipper is part of Ursa Major (the Great Bear). It is fairly easy to find in the sky. ...
Lecture Notes – Galaxies
... Discovered in the 1940s by Carl Seyfert and appear as normal spirals but with very bright nuclei and emit strong non-thermal spectrum. The visible spectrum contains broad (5 000–10 000 km/s) emission lines indicating clouds of gas moving at very high speeds in the nucleus of the galaxy. 1% of spiral ...
... Discovered in the 1940s by Carl Seyfert and appear as normal spirals but with very bright nuclei and emit strong non-thermal spectrum. The visible spectrum contains broad (5 000–10 000 km/s) emission lines indicating clouds of gas moving at very high speeds in the nucleus of the galaxy. 1% of spiral ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.