personal rights of identity in the sneetches and yertle the turtle
... seek to maintain or create new legal distinctions. Dr. Seuss’s 1961 story The Sneetches provides an excellent lens through which to explore the past, present, and future of this struggle. In The Sneetches, there existed two classes of persons: the Star-Belly Sneetches—who had stars on their bellies— ...
... seek to maintain or create new legal distinctions. Dr. Seuss’s 1961 story The Sneetches provides an excellent lens through which to explore the past, present, and future of this struggle. In The Sneetches, there existed two classes of persons: the Star-Belly Sneetches—who had stars on their bellies— ...
A seismic and gravitationally-bound double star observed by Kepler
... pair appears to also be gravitationally bound since they have the same parallax and proper motion (van Leeuwen 2007) but their relative motion observed between 1850 and 2007 does not allow one to derive a meaningful orbit. These binary systems are clearly resolved such that the time series of each c ...
... pair appears to also be gravitationally bound since they have the same parallax and proper motion (van Leeuwen 2007) but their relative motion observed between 1850 and 2007 does not allow one to derive a meaningful orbit. These binary systems are clearly resolved such that the time series of each c ...
REVIEWS The formation of the first stars and galaxies Volker Bromm
... Simply put, population III.1 stars are locally the very first luminous objects, whereas population III.2 stars are those metal-free stars formed from gas that was already affected by previous generations of stars. Population II stars have enough metals to affect their formation and/or their evolutio ...
... Simply put, population III.1 stars are locally the very first luminous objects, whereas population III.2 stars are those metal-free stars formed from gas that was already affected by previous generations of stars. Population II stars have enough metals to affect their formation and/or their evolutio ...
Blackholes - Indiana University Astronomy
... •from 1.4 to about 3 solar masses •Made of pure neutrons – a giant atomic nucleus •About 20 km in diameter •One cc would weigh about a million tons Black Holes •Formed in Supernova explosions •Usually a few times the mass of the Sun •A solar mass black hole is about 3 km in ...
... •from 1.4 to about 3 solar masses •Made of pure neutrons – a giant atomic nucleus •About 20 km in diameter •One cc would weigh about a million tons Black Holes •Formed in Supernova explosions •Usually a few times the mass of the Sun •A solar mass black hole is about 3 km in ...
Contrast the old definition of constellation with the
... If all stars are circumpolar if you lived at the north pole, and all stars rise and set if you lived on the equator, what can you state about the motion of stars if you lived in between the north pole and the equator? ...
... If all stars are circumpolar if you lived at the north pole, and all stars rise and set if you lived on the equator, what can you state about the motion of stars if you lived in between the north pole and the equator? ...
PDF only
... properties and of the physical processes involved: on top of being impossible in such a short lecture format, this would be useless to an audience of nuclear physicists, who are trained in the physics of microscopic systems of degenerate nucleons, but are probably not familiar with astrophysical iss ...
... properties and of the physical processes involved: on top of being impossible in such a short lecture format, this would be useless to an audience of nuclear physicists, who are trained in the physics of microscopic systems of degenerate nucleons, but are probably not familiar with astrophysical iss ...
(March 2004) (ppt-format) - RHIG
... galaxy obtained by dividing the Galaxy's total mass by the mass of a typical star (e.g., 1 solar mass). The result is about 200 billion stars! The actual number of stars could be several tens of billions less or more than this approximate value. All of these numbers are based on luminous matte ...
... galaxy obtained by dividing the Galaxy's total mass by the mass of a typical star (e.g., 1 solar mass). The result is about 200 billion stars! The actual number of stars could be several tens of billions less or more than this approximate value. All of these numbers are based on luminous matte ...
Galaxy Properties - Tufts Institute of Cosmology
... the arms are star forming regions. The massive, hot, young and luminous stars dominate the overall light, thus giving it a bluish hue. The bright yellowish looking regions, mostly the bulge, also have some young stars, however, since there is relatively more dust in the bulge, we see only the longer ...
... the arms are star forming regions. The massive, hot, young and luminous stars dominate the overall light, thus giving it a bluish hue. The bright yellowish looking regions, mostly the bulge, also have some young stars, however, since there is relatively more dust in the bulge, we see only the longer ...
ISOLATED, MASSIVE SUPERGIANTS NEAR THE GALACTIC
... with the radio H ii region H2 and a newly identified star that we refer to as CXOGC J174516.1290315. The infrared spectra of both stars exhibit very strong Br and He i lines and resemble those of massive supergiants that have evolved off of the main sequence but not yet reached the Wolf-Rayet phas ...
... with the radio H ii region H2 and a newly identified star that we refer to as CXOGC J174516.1290315. The infrared spectra of both stars exhibit very strong Br and He i lines and resemble those of massive supergiants that have evolved off of the main sequence but not yet reached the Wolf-Rayet phas ...
Neutron stars: compact objects with relativistic gravity
... was clearly established that the energy is expelled from the system at the rate gravitational waves would take away as predicted within general relativity [30–34]. Given that the strong surface gravity of neutron stars is at a regime not probed by the solar system tests and binary pulsars, one may h ...
... was clearly established that the energy is expelled from the system at the rate gravitational waves would take away as predicted within general relativity [30–34]. Given that the strong surface gravity of neutron stars is at a regime not probed by the solar system tests and binary pulsars, one may h ...
Neutron star to strange star - Institute of Physics, Bhubaneswar
... direction of the magnetic field ( Chakrabarty et al. PRL 78, 2898, ...
... direction of the magnetic field ( Chakrabarty et al. PRL 78, 2898, ...
Properties of long gamma-ray bursts from massive compact binaries
... We use the binary population of Church et al. [7], within which we searched for double blackhole binaries that satisfy the criterion of Levan et al. [6]. In summary, this requires that the binary be tight enough that, assuming tidal locking, the core is spun up sufficiently that its outer parts form ...
... We use the binary population of Church et al. [7], within which we searched for double blackhole binaries that satisfy the criterion of Levan et al. [6]. In summary, this requires that the binary be tight enough that, assuming tidal locking, the core is spun up sufficiently that its outer parts form ...
NATS 1311 From the Cosmos to Earth
... shell outside the core begins. The high rate of fusion in the hydrogen shell forces the star's upper layers to expand outward causing the star to expand greatly in size, moving location on HR diagram up and to the right to the giant ...
... shell outside the core begins. The high rate of fusion in the hydrogen shell forces the star's upper layers to expand outward causing the star to expand greatly in size, moving location on HR diagram up and to the right to the giant ...
3-D Visualization of Cataclysmic Variables With IDL by:
... designed for this specific purpose was already in existence; created by Dr. Cash and previous research students under her supervision. The ultimate goal of this summer's work was to improve upon the already existing program and extend it to a point where it could be efficiently used for other applic ...
... designed for this specific purpose was already in existence; created by Dr. Cash and previous research students under her supervision. The ultimate goal of this summer's work was to improve upon the already existing program and extend it to a point where it could be efficiently used for other applic ...
CONSTELLATION TAURUS, THE BULL The Taurus constellation
... visual magnitude varying between 0.75 and 0.95. It is the brightest star in the constellation Taurus and the 13th brightest in the sky. It has a diameter 44 times that of the Sun and is about 425 times more luminous. The star lies approximately 65 light years from Earth. It is classified as a slow i ...
... visual magnitude varying between 0.75 and 0.95. It is the brightest star in the constellation Taurus and the 13th brightest in the sky. It has a diameter 44 times that of the Sun and is about 425 times more luminous. The star lies approximately 65 light years from Earth. It is classified as a slow i ...
Introduc on to the Fundamental Astrophysics Course
... Being more specific … Stellar Evolu)on • Stellar evolu)on is the process by which a star undergoes a sequence of radical changes during its life)me. • Depending on the mass of the star, this lif ...
... Being more specific … Stellar Evolu)on • Stellar evolu)on is the process by which a star undergoes a sequence of radical changes during its life)me. • Depending on the mass of the star, this lif ...
Detection of isolated population III stars with the James Webb Space
... that the lensed stars are too faint, but that their surface number densities are too low. To detect even one 60 M⊙ population III star when pointing JWST through the galaxy cluster MACS J0717.5+3745, the lensing cluster with the largest Einstein radius detected so far, the cosmic star formation rate ...
... that the lensed stars are too faint, but that their surface number densities are too low. To detect even one 60 M⊙ population III star when pointing JWST through the galaxy cluster MACS J0717.5+3745, the lensing cluster with the largest Einstein radius detected so far, the cosmic star formation rate ...
The Initial Mass Function
... Reipurth, D. Jewitt, and K. Keil (eds), University of Arizona Press, ...
... Reipurth, D. Jewitt, and K. Keil (eds), University of Arizona Press, ...
The Stellar Population And Origin Of The Mysterious K.V. Getman
... The broad age spread found in CG12 is inconsistent with the rapid timescale (few 105 yr) predicted by simple triggered star formation models of CGs. However, more complex models of shock triggered star formation might explain the age distribution of CG12 stars. Two possibilities can be considered. F ...
... The broad age spread found in CG12 is inconsistent with the rapid timescale (few 105 yr) predicted by simple triggered star formation models of CGs. However, more complex models of shock triggered star formation might explain the age distribution of CG12 stars. Two possibilities can be considered. F ...
Barium Stars: Theoretical Interpretation
... Our models are based on franec (Frascati RaphsonNewton Evolutionary Code, Chieffi & Straniero 1989), coupled with a post-process code that includes a full network up to bismuth. According to franec, TDU starts after a limited number of TPs. TDU ceases when the mass of the envelope decreases by mass l ...
... Our models are based on franec (Frascati RaphsonNewton Evolutionary Code, Chieffi & Straniero 1989), coupled with a post-process code that includes a full network up to bismuth. According to franec, TDU starts after a limited number of TPs. TDU ceases when the mass of the envelope decreases by mass l ...
Determining the Nature of a Double Star: The Law of Conservation
... stars. These criteria determine if the observed velocity is within the allowed limits according to the orbital energy conservation equation. They have been used by the LIADA Double Star Section for many years. Finally, I propose to unify these methods and give some examples of applicability. ...
... stars. These criteria determine if the observed velocity is within the allowed limits according to the orbital energy conservation equation. They have been used by the LIADA Double Star Section for many years. Finally, I propose to unify these methods and give some examples of applicability. ...
FRIENDS OF THE PLANETARIUM NEWSLETTER
... month it rises at 04 23 and at 05 22 by month’s end. Venus starts the month in the constellation of Pisces, moving into Aries on June 2 and finally into Taurus on June 19. Winter Solstice The Southern hemisphere Winter Solstice is at 00 26 on June 22. This is when the Sun is at its most Northerly po ...
... month it rises at 04 23 and at 05 22 by month’s end. Venus starts the month in the constellation of Pisces, moving into Aries on June 2 and finally into Taurus on June 19. Winter Solstice The Southern hemisphere Winter Solstice is at 00 26 on June 22. This is when the Sun is at its most Northerly po ...
Energy in The Universe - Physics Department, Princeton University
... from this rule are masses of planetary size or smaller, in which gravitational contraction is halted by the mechanical incompressibility of the material before the ignition point of thermonuclear re actions is reached. The preponderance of hydrogen in the universe ensures that our night sky is fill ...
... from this rule are masses of planetary size or smaller, in which gravitational contraction is halted by the mechanical incompressibility of the material before the ignition point of thermonuclear re actions is reached. The preponderance of hydrogen in the universe ensures that our night sky is fill ...
Main sequence
In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell. Stars on this band are known as main-sequence stars or ""dwarf"" stars.After a star has formed, it generates thermal energy in the dense core region through the nuclear fusion of hydrogen atoms into helium. During this stage of the star's lifetime, it is located along the main sequence at a position determined primarily by its mass, but also based upon its chemical composition and other factors. All main-sequence stars are in hydrostatic equilibrium, where outward thermal pressure from the hot core is balanced by the inward pressure of gravitational collapse from the overlying layers. The strong dependence of the rate of energy generation in the core on the temperature and pressure helps to sustain this balance. Energy generated at the core makes its way to the surface and is radiated away at the photosphere. The energy is carried by either radiation or convection, with the latter occurring in regions with steeper temperature gradients, higher opacity or both.The main sequence is sometimes divided into upper and lower parts, based on the dominant process that a star uses to generate energy. Stars below about 1.5 times the mass of the Sun (or 1.5 solar masses (M☉)) primarily fuse hydrogen atoms together in a series of stages to form helium, a sequence called the proton–proton chain. Above this mass, in the upper main sequence, the nuclear fusion process mainly uses atoms of carbon, nitrogen and oxygen as intermediaries in the CNO cycle that produces helium from hydrogen atoms. Main-sequence stars with more than two solar masses undergo convection in their core regions, which acts to stir up the newly created helium and maintain the proportion of fuel needed for fusion to occur. Below this mass, stars have cores that are entirely radiative with convective zones near the surface. With decreasing stellar mass, the proportion of the star forming a convective envelope steadily increases, whereas main-sequence stars below 0.4 M☉ undergo convection throughout their mass. When core convection does not occur, a helium-rich core develops surrounded by an outer layer of hydrogen.In general, the more massive a star is, the shorter its lifespan on the main sequence. After the hydrogen fuel at the core has been consumed, the star evolves away from the main sequence on the HR diagram. The behavior of a star now depends on its mass, with stars below 0.23 M☉ becoming white dwarfs directly, whereas stars with up to ten solar masses pass through a red giant stage. More massive stars can explode as a supernova, or collapse directly into a black hole.