Nucleosynthesis and Chemical Evolution of Oxygen
... only one particular model, its yields are fairly representative of the ejecta from any star more than ten times the mass of the Sun. Chemical evolution models using detailed stellar model yields have long shown that the Galaxy’s supply 16O is dominantly from massive stars (e.g., B. M. Tinsley 1980—“ ...
... only one particular model, its yields are fairly representative of the ejecta from any star more than ten times the mass of the Sun. Chemical evolution models using detailed stellar model yields have long shown that the Galaxy’s supply 16O is dominantly from massive stars (e.g., B. M. Tinsley 1980—“ ...
The colours of the Universe, the amateur astronomical spectroscopy.
... elements such as: Balmer's hydrogen spectral series, helium, nitrogen and carbon, which prove their presence in the Mintaka's chromospheres. In the stars of high temperature, spectral type O, there are ionized atoms, because at such a high temperature bonds between the atomic nucleus and the electro ...
... elements such as: Balmer's hydrogen spectral series, helium, nitrogen and carbon, which prove their presence in the Mintaka's chromospheres. In the stars of high temperature, spectral type O, there are ionized atoms, because at such a high temperature bonds between the atomic nucleus and the electro ...
Galaxy Classification - VCI
... he began to classify them into different types. The shape and color of a galaxy tell us a lot about the events that have happened within that galaxy. ...
... he began to classify them into different types. The shape and color of a galaxy tell us a lot about the events that have happened within that galaxy. ...
Searching for the oldest, most metal-poor stars in the SkyMapper Survey
... termed Population III stars, began to form a few hundred million years after the Big Bang. These stars were very massive - much more massive than typical stars observed today in the universe. Like all stars, the Population III stars performed nuclear fusion in their cores. Hydrogen atoms are fused t ...
... termed Population III stars, began to form a few hundred million years after the Big Bang. These stars were very massive - much more massive than typical stars observed today in the universe. Like all stars, the Population III stars performed nuclear fusion in their cores. Hydrogen atoms are fused t ...
SRMP Stars Curriculum - American Museum of Natural History
... ACTIVITY: Stellar Temperature and Distance In this activity, students will be given two tables of data – one of nearby stars, and one of bright stars in our sky. There is some overlap in stars, but most of them are separate. The table includes each star’s name, spectral type, apparent and absolute m ...
... ACTIVITY: Stellar Temperature and Distance In this activity, students will be given two tables of data – one of nearby stars, and one of bright stars in our sky. There is some overlap in stars, but most of them are separate. The table includes each star’s name, spectral type, apparent and absolute m ...
Quasars
... Galactic nuclei have different degrees of activity in the sense they emit variable and intense radiation. Quasars are the brightest type of active galactic nucleus. The viewpoint now is that a supermassive black hole is consuming stars and gas and dust clouds in their near vacinity and creating an a ...
... Galactic nuclei have different degrees of activity in the sense they emit variable and intense radiation. Quasars are the brightest type of active galactic nucleus. The viewpoint now is that a supermassive black hole is consuming stars and gas and dust clouds in their near vacinity and creating an a ...
Betelgeuse: an unauthorized biography
... (i.e. main sequence) mass 15+2 –5 M, the 15 M corresponding (with mass loss rates from Schaller et al.) to about 13.7 M now. This mass, combined with a radius of 780, 700 or 640 R implies a surface gravity of log g = –0.20, –0.11 and –0.04 respectively, very much in line with the value 0.0 (with ...
... (i.e. main sequence) mass 15+2 –5 M, the 15 M corresponding (with mass loss rates from Schaller et al.) to about 13.7 M now. This mass, combined with a radius of 780, 700 or 640 R implies a surface gravity of log g = –0.20, –0.11 and –0.04 respectively, very much in line with the value 0.0 (with ...
Introduction to Galaxies - West Jefferson Local Schools
... The spiral galaxies M 91 (left) and M 109 (right) have bars across their nuclei from which spiral arms unwind. In virtually all spirals (barred or not) the galaxies rotate such that the spiral arms trail behind in the rotation. The Milky Way is thought to be a barred spiral galaxy. ...
... The spiral galaxies M 91 (left) and M 109 (right) have bars across their nuclei from which spiral arms unwind. In virtually all spirals (barred or not) the galaxies rotate such that the spiral arms trail behind in the rotation. The Milky Way is thought to be a barred spiral galaxy. ...
Lecture 12
... requires measuring the entire EM spectrum of a source, which is impossible with a single type detector. • Bolometric fluxes have to be inferred by knowledge of the physics producing the luminous source for which you have partial information, or pieced together from observations at all parts of the E ...
... requires measuring the entire EM spectrum of a source, which is impossible with a single type detector. • Bolometric fluxes have to be inferred by knowledge of the physics producing the luminous source for which you have partial information, or pieced together from observations at all parts of the E ...
Primordial planets, comets and moons foster life in the cosmos
... of the plasma when it first fragmented at 1012 s. It is no coincidence that this is the observed density of old globular star clusters OGCs. Clumps of planet-mass clouds are termed proto-globular-starclusters PGCs. No dark age exists for HGD because the first stars appear in a gravitational free fal ...
... of the plasma when it first fragmented at 1012 s. It is no coincidence that this is the observed density of old globular star clusters OGCs. Clumps of planet-mass clouds are termed proto-globular-starclusters PGCs. No dark age exists for HGD because the first stars appear in a gravitational free fal ...
Modeling White Dwarf Star Magnetization - Blogs at H-SC
... and because there is no more fusion, or producing heat energy, the cooling process slows down gradually. A white dwarf star is believed white due to its color of the temperature on H-R diagram. However, most of the white dwarf stars have the surface temperature that is still hotter than that of the ...
... and because there is no more fusion, or producing heat energy, the cooling process slows down gradually. A white dwarf star is believed white due to its color of the temperature on H-R diagram. However, most of the white dwarf stars have the surface temperature that is still hotter than that of the ...
Galaxies and Their Structure
... radiation from a tiny region in the galactic core • Radio Galaxies • Galaxies with massive radio emissions from jets • Quasars • Distant active/radio galaxies • Seyfert Galaxies a spiral galaxy with abnormally luminous core from a region less than a ly year across • Jets in Quasars sometimes move wi ...
... radiation from a tiny region in the galactic core • Radio Galaxies • Galaxies with massive radio emissions from jets • Quasars • Distant active/radio galaxies • Seyfert Galaxies a spiral galaxy with abnormally luminous core from a region less than a ly year across • Jets in Quasars sometimes move wi ...
arXiv:astro-ph/0411296v1 11 Nov 2004
... stars (Speck et al. 1997), it results in a feature which peaks at 11.3 µm and is too narrow to fit the broad 12 µm ‘plateau’ feature. However, in the absence of an alternative identification, we have used α-SiC optical constants (Pègouriè 1988) to produce a feature in this wavelength range. The 81 ...
... stars (Speck et al. 1997), it results in a feature which peaks at 11.3 µm and is too narrow to fit the broad 12 µm ‘plateau’ feature. However, in the absence of an alternative identification, we have used α-SiC optical constants (Pègouriè 1988) to produce a feature in this wavelength range. The 81 ...
White dwarf cooling sequences and cosmochronology
... remaining quantities, the initial mass function, (M), and the star formation rate, (t), are not known a priori and depend on the astronomical properties of the stellar population under study. Since the total density of white dwarfs of a given population is not usually well known, to compare the th ...
... remaining quantities, the initial mass function, (M), and the star formation rate, (t), are not known a priori and depend on the astronomical properties of the stellar population under study. Since the total density of white dwarfs of a given population is not usually well known, to compare the th ...
Teacher`s Guide - Cornell Science Inquiry Partnerships
... This activity makes an analogy between stars and humans, which are easier to relate to. By having students graph properties of populations of humans based on a “snapshot” in time (i.e., a photograph or a census) and seeing what they can infer about these populations and how they change, the activity ...
... This activity makes an analogy between stars and humans, which are easier to relate to. By having students graph properties of populations of humans based on a “snapshot” in time (i.e., a photograph or a census) and seeing what they can infer about these populations and how they change, the activity ...
Brown Dwarfs - The University of Toledo
... Not defined by spectral type, but includes late M,L,and T spectral types. No central, stable H fusion. Convection is the dominant form of energy transport. (M < 0.3M) Defined by mass (but hard to directly determine): ...
... Not defined by spectral type, but includes late M,L,and T spectral types. No central, stable H fusion. Convection is the dominant form of energy transport. (M < 0.3M) Defined by mass (but hard to directly determine): ...
The Mass of Quasar Broad Emission Line Regions
... the ratio of radiation to gas pressures, and nH, 10 is the density of hydrogen in units of 1010 cm3. A cursory reading of these texts would leave the impression that MBLR is anywhere from 2 to 2000 M. However, there are different choices of luminosity and density (and also of other parameters) buri ...
... the ratio of radiation to gas pressures, and nH, 10 is the density of hydrogen in units of 1010 cm3. A cursory reading of these texts would leave the impression that MBLR is anywhere from 2 to 2000 M. However, there are different choices of luminosity and density (and also of other parameters) buri ...
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.