Compact objects for everyone: I. White dwarf stars - Rose
... Fermi–Thomas distance, the analogue for more massive atoms of the Bohr radius for hydrogen. The density of a collapsed star is so high that the mean distance between nuclei is less than the Fermi–Thomas distance: the matter is ‘pressure-ionized’, with the electrons forming an effectively free gas. H ...
... Fermi–Thomas distance, the analogue for more massive atoms of the Bohr radius for hydrogen. The density of a collapsed star is so high that the mean distance between nuclei is less than the Fermi–Thomas distance: the matter is ‘pressure-ionized’, with the electrons forming an effectively free gas. H ...
Energy Production in Stars
... reaction with protons will lead to the emission of an cx-particle so that the original nucleus is permanently destroyed. For all nuclei heavier than fluorine, only radiative capture of the protons occurs, also destroying the original nucleus. Oxygen and fluorine reactions mostly lead back to nitroge ...
... reaction with protons will lead to the emission of an cx-particle so that the original nucleus is permanently destroyed. For all nuclei heavier than fluorine, only radiative capture of the protons occurs, also destroying the original nucleus. Oxygen and fluorine reactions mostly lead back to nitroge ...
Dynamical Petschek Reconnection
... conductive plasma of the solar corona. Petschek proposed another reconnection theory, in which small magnetic diffusion region realizes efficient reconnection with the energy conversion occurring in slow mode MHD shocks. However, recent numerical simulations suggest that Petschek reconnection is not ...
... conductive plasma of the solar corona. Petschek proposed another reconnection theory, in which small magnetic diffusion region realizes efficient reconnection with the energy conversion occurring in slow mode MHD shocks. However, recent numerical simulations suggest that Petschek reconnection is not ...
STUDY OF UMBRA-PENUMBRA AREA RATIO OF SUNSPOTS
... cycle. The two factors which determine the most likely nuclear reactions are the abundance of the reacting species and the reaction probability at the temperatures prevailing in the solar core. The Sun’s low density indicates that it is made of very light elements, mostly hydrogen and helium. Also, ...
... cycle. The two factors which determine the most likely nuclear reactions are the abundance of the reacting species and the reaction probability at the temperatures prevailing in the solar core. The Sun’s low density indicates that it is made of very light elements, mostly hydrogen and helium. Also, ...
Real World Science: The Solar System
... own unique qualities. For example, Saturn is surrounded by rings made of ice and rock. One of Saturn’s moons, Titan, is different than other moons because it has its own atmosphere. Moons like Titan are known as satellites because they orbit larger ...
... own unique qualities. For example, Saturn is surrounded by rings made of ice and rock. One of Saturn’s moons, Titan, is different than other moons because it has its own atmosphere. Moons like Titan are known as satellites because they orbit larger ...
The quest for life in extrasolar planets
... relatively small rocky planets, close to the Sun giant gaseous/icy planets, far away from the Sun ...
... relatively small rocky planets, close to the Sun giant gaseous/icy planets, far away from the Sun ...
THE NAMING OF STARS AND THE STUDY OF PROTOSTARS D. R.
... It is considered that stars are formed from protostars which are large clouds of material which mainly under gravity, coalesce to give 1, or 2 or 3 or more centres. Some of these centres are sufficiently large that they give stars. The result is that about 65% of stars are in binary systems and less ...
... It is considered that stars are formed from protostars which are large clouds of material which mainly under gravity, coalesce to give 1, or 2 or 3 or more centres. Some of these centres are sufficiently large that they give stars. The result is that about 65% of stars are in binary systems and less ...
The stellar populations of Lyman Break Galaxies at z~5 in...
... synthesis models. The comparisons of the distributions of parameters for our z~5 sample with those for z=2-3 samples in fixed rest-frame UV and optical ranges shows the increase of the stellar mass from z~5 to z=2-3 and that the z~5 galaxies are relatively younger than the z=2-3 galaxies. The star f ...
... synthesis models. The comparisons of the distributions of parameters for our z~5 sample with those for z=2-3 samples in fixed rest-frame UV and optical ranges shows the increase of the stellar mass from z~5 to z=2-3 and that the z~5 galaxies are relatively younger than the z=2-3 galaxies. The star f ...
Document
... About 150 planets discovered around other stars. Most are massive and close to the star! Why? vstar α Mplanet/√a The closer the planet the star and the larger the mass, the larger the velocity of the star. That is why most of the discovered planets have a distance of less than 1 AU and mass like Ju ...
... About 150 planets discovered around other stars. Most are massive and close to the star! Why? vstar α Mplanet/√a The closer the planet the star and the larger the mass, the larger the velocity of the star. That is why most of the discovered planets have a distance of less than 1 AU and mass like Ju ...
Who’s Afraid of a Stellar Superflare? Rachel Osten GSFC
... investigated the putative effects of a SNe; gamma rays and cosmic rays can cause significant disruption of terrestrial ozone for d<8 pc. Based on SN rate, this is an unlikely mass ...
... investigated the putative effects of a SNe; gamma rays and cosmic rays can cause significant disruption of terrestrial ozone for d<8 pc. Based on SN rate, this is an unlikely mass ...
Astronomy Practice Test 1
... B. Earth's gravity has less effect on objects as they get farther away from Earth. C. the mass of the object is less in space. D. the space shuttle's engines cause too much vibration for objects to remain still. 23. Earth is made of solid materials. Jupiter, Saturn, Uranus, and Neptune are all made ...
... B. Earth's gravity has less effect on objects as they get farther away from Earth. C. the mass of the object is less in space. D. the space shuttle's engines cause too much vibration for objects to remain still. 23. Earth is made of solid materials. Jupiter, Saturn, Uranus, and Neptune are all made ...
![Chapter 4 [PDF only] - Princeton University Press](http://s1.studyres.com/store/data/016931743_1-7c8ec22374457bf50a0a03f55488ddc7-300x300.png)
Chapter 4 [PDF only] - Princeton University Press
... So far, we have considered only stars in static equilibrium, and found that a star of a given mass and composition has a unique, fully determined, structure. However, it is now also clear that true equilibrium cannot exist. Nuclear reactions in the central regions synthesize hydrogen into helium, an ...
... So far, we have considered only stars in static equilibrium, and found that a star of a given mass and composition has a unique, fully determined, structure. However, it is now also clear that true equilibrium cannot exist. Nuclear reactions in the central regions synthesize hydrogen into helium, an ...
Document
... have lower [α/Fe] than in inner parts/solar neighborhood – shortest delay time for Type Ia ...
... have lower [α/Fe] than in inner parts/solar neighborhood – shortest delay time for Type Ia ...
The BI-Gravitational Solar System: Center-Point
... masses and gravity pull of the nine planets upon the Sun, and vice versa. Obviously, the numerical rendering of the barycenter is a purely theoretical exercise based upon the concept of a centerpoint of gravity between two objects with definite and commensurable mass. To illustrate the difficulty of ...
... masses and gravity pull of the nine planets upon the Sun, and vice versa. Obviously, the numerical rendering of the barycenter is a purely theoretical exercise based upon the concept of a centerpoint of gravity between two objects with definite and commensurable mass. To illustrate the difficulty of ...
Dark Matter Concept Questions
... (CDMS) located 700 m underground in an abandoned mine. It involves a number of 250 g crystals of germanium (Ge) that are cooled down to just above absolute zero (–273o C). According to the weakly interacting massive particle (WIMP) theory of dark matter, billions of WIMPs from outer space are rainin ...
... (CDMS) located 700 m underground in an abandoned mine. It involves a number of 250 g crystals of germanium (Ge) that are cooled down to just above absolute zero (–273o C). According to the weakly interacting massive particle (WIMP) theory of dark matter, billions of WIMPs from outer space are rainin ...
FP11: DRAKE et al. - Astronomical Institute WWW Homepage
... rotational phases of HD 3980 were calculated using the ephemeris from Maitzen et al. (1980). Two “Li spots” are observed on the surface of the star. The Li I line originated in spot 1 appears at the phase φ = – 0.146 = 0.832 and moves to the red up to the phase φ = 0.146. The second Li-rich spot (sp ...
... rotational phases of HD 3980 were calculated using the ephemeris from Maitzen et al. (1980). Two “Li spots” are observed on the surface of the star. The Li I line originated in spot 1 appears at the phase φ = – 0.146 = 0.832 and moves to the red up to the phase φ = 0.146. The second Li-rich spot (sp ...