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THE SHAPES OF ATOMIC LINES FROM THE SURFACES OF
THE SHAPES OF ATOMIC LINES FROM THE SURFACES OF

Is $^ 6$ Li in metal-poor halo stars produced in situ by solar
Is $^ 6$ Li in metal-poor halo stars produced in situ by solar

... account. Second, it is very likely that most halo stars were much more active in their youth than the contemporary Sun. Indeed stellar rotation being the decisive factor of solar-like activity of dwarf stars, magnetic braking during the main sequence leads to a well-known decay with stellar age of c ...
Statistical analysis of stellar evolution
Statistical analysis of stellar evolution

... of the Sun, M , its core will ignite in a thermonuclear reaction that is powered by the fusion of hydrogen into helium. This reaction at the star’s core can continue for millions or billions of years depending on the original mass and composition of the star. More massive stars are denser, and thus ...
Entropy
Entropy

... follows: Teff ʘ = (57±2)∙102 K, Lʘ = (3.8±0.6)∙1026 W, Σʘ = (9±1)∙1022 W ∙ K-1, and ΣV ʘ = (6±2)∙10-5 W ∙ K-1 ∙ m-3. These results conform well with the data given in Refs. [14, 15, 26]. Calculation results of Σ and ΣV for the MS stars are shown in Figure 1-5.3. Using these results, the following co ...
sections 16-18 instructor notes
sections 16-18 instructor notes

... are nearby halo stars that have high apparent velocities relative to the Sun because most of their orbital motion is in the direction of the Galactic centre. The results depend upon the assumption that all such stars are bound to the Galaxy and that their orbits are governed by the mass of the Galax ...
Homework #9 (Ch. 21)
Homework #9 (Ch. 21)

CH14.AST1001.S15.EDS
CH14.AST1001.S15.EDS

... • As a white dwarf's mass approaches 1.4MSun, its electrons must move at nearly the speed of light. • Because nothing can move faster than light, a white dwarf cannot be more massive than 1.4MSun, the white dwarf limit (also known as the Chandrasekhar limit). © 2015 Pearson Education, Inc. ...
The surface composition of Beta Pictoris
The surface composition of Beta Pictoris

... et al. 1995; Grady et al. 1996). In view of this the absence of surface anomalies in a star like β Pic—with its spectacular disk of gas and dust—is puzzling. A possible explanation is that accretion does not occur at all, or at a rate which is too small to compete with meridional mixing. On the basi ...
Andromeda: Daughter of Cassiopeia Ἀνδρομέδη Kaitlyn Heaton
Andromeda: Daughter of Cassiopeia Ἀνδρομέδη Kaitlyn Heaton

Finding the Most Distant Quasars Using Bayesian Selection Methods
Finding the Most Distant Quasars Using Bayesian Selection Methods

... for a good candidate, given that there are so many more stars than quasars. Combining these considerations gives a clear, if qualitative, scheme for prioritising the candidates: identify those which are extreme outliers from the stellar distribution but are also consistent with being DQs. The remain ...
ASTRO-114--Lecture 47-
ASTRO-114--Lecture 47-

... maybe have formed in the past and left some of the clo ud behind. So we’re pretty sure we’re getting more or less a map of the galaxy by looking at hydrogen radiation. Not actually photographing it, but we’re making measurements that help us to map it. Now, notice that spiral pattern there in the ga ...
Local Group Encyclopedia of Astronomy & Astrophysics eaa.iop.org Mario L Mateo
Local Group Encyclopedia of Astronomy & Astrophysics eaa.iop.org Mario L Mateo

... Much of the recent success in finding new Local Group members is due to the availability of the many largescale photographic surveys of the sky carried out since the seminal Palomar Sky Survey of the 1950s. Soon after these surveys were begun, visual searches of the photographic plates identified ne ...
PDF Full-text
PDF Full-text

... the photodissociation rate for H2 O in exoplanets with solar-type and M dwarf host stars including the observed UV fluxes and Lyman-α corrected for interstellar absorption to evaluate the H2 O loss rate. At this time, however, there are very few disequilibrium chemistry calculations that include obs ...
Neutron Stars
Neutron Stars

... were apparently affecting the orbital motion, and the momentus discovery that the orbit was slowly shrinking, presumably due to the predicted emission of gravitational radiation, allowed the measurements of the individual masses in this system. The invisible companion’s mass turned out to be nearly e ...
Homework Due
Homework Due

View the pdf here
View the pdf here

... but it is dedicated to von humboldt. he contrasts the positions of aristotle, bacon, hume, kant, bentham, and mill, for example. he quotes them. it is a defense of imagination, intuition, and improvisation in all the paths of human inquiry, including the sciences, and it is a reasoned defense by a c ...
Annual report 2004 - Département d`Astrophysique, Géophysique et
Annual report 2004 - Département d`Astrophysique, Géophysique et

... eccentric orbit (e=0.81) and similar component masses with a mass ratio M1/M2=1.02. Cen forms a challenge for current evolution scenarios in close binaries and it is also a puzzle how a massive binary with such a large eccentricity could have formed in the first place. Both the primary and the secon ...
Relativity, Space-Time And Cosmology
Relativity, Space-Time And Cosmology

... During the nineteenth century, more accurate instruments were used to test Newton’s theory, these observations uncovered some slight discrepancies. Albert Einstein proposed his theories of Relativity, which explained the newly observed facts and made more predictions. Those predictions have now been ...
G060048-00 - DCC
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What problems of physics and astrophysics seem
What problems of physics and astrophysics seem

... There, each problem of the `list' is commented on. I cannot do the same here, and therefore I shall restrict myself to separate, sometimes fragmentary remarks and comments 1. The basic goal is to elucidate the development of physics over the last four or five years, that is, after the book [2] was p ...
KINEMATIC DISCOVERY OF A STELLAR STREAM LOCATED IN
KINEMATIC DISCOVERY OF A STELLAR STREAM LOCATED IN

bars and secular evolution
bars and secular evolution

Mergers of massive main sequence binaries
Mergers of massive main sequence binaries

... content which leads to high luminosities. We then used the data of this analysis to simulate a cluster of a large number of stars with a binary percentage of 50% which formed instantaneously. The result of this simulation is that merger stars of close massive main-sequence binaries are dominant amon ...
1: Properties of Pulsars
1: Properties of Pulsars

... where G is the gravitational constant. The period of the Crab pulsars hence requires a maximum radius of only 105 metres which is two orders of magnitude smaller than what is typical for white dwarfs. Only neutron stars were left as a possible explanation. Periods for radial oscillations of neutron ...
ATLAS lifts the Cup: discovery of a new Milky Way satellite in Crater⋆†
ATLAS lifts the Cup: discovery of a new Milky Way satellite in Crater⋆†

... No globular cluster has ever accomplished the feat of prolonging its star formation by several Gyr. Therefore, if our hypothesis that the blue bright stars in Crater are blue loop giants is correct, the new satellite should be classified as a dwarf galaxy with unusual properties. Note that only 10◦ ...
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Future of an expanding universe

Observations suggest that the expansion of the universe will continue forever. If so, the universe will cool as it expands, eventually becoming too cold to sustain life. For this reason, this future scenario is popularly called the Big Freeze.If dark energy—represented by the cosmological constant, a constant energy density filling space homogeneously, or scalar fields, such as quintessence or moduli, dynamic quantities whose energy density can vary in time and space—accelerates the expansion of the universe, then the space between clusters of galaxies will grow at an increasing rate. Redshift will stretch ancient, incoming photons (even gamma rays) to undetectably long wavelengths and low energies. Stars are expected to form normally for 1012 to 1014 (1–100 trillion) years, but eventually the supply of gas needed for star formation will be exhausted. And as existing stars run out of fuel and cease to shine, the universe will slowly and inexorably grow darker, one star at a time. According to theories that predict proton decay, the stellar remnants left behind will disappear, leaving behind only black holes, which themselves eventually disappear as they emit Hawking radiation. Ultimately, if the universe reaches a state in which the temperature approaches a uniform value, no further work will be possible, resulting in a final heat death of the universe.
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