lecture18
... The universe started out containing mainly hydrogen (90%) and helium (about 10%), formed at the birth of the universe. The nuclear burning in stars transforms some of this material into heavier elements – carbon, oxygen, calcium etc. up to iron. When a supernova erupts, these newly formed elements a ...
... The universe started out containing mainly hydrogen (90%) and helium (about 10%), formed at the birth of the universe. The nuclear burning in stars transforms some of this material into heavier elements – carbon, oxygen, calcium etc. up to iron. When a supernova erupts, these newly formed elements a ...
2015 SAO Summer Intern AAS Abstracts - Harvard
... throughout our Galaxy as well as others, with the star formation rate (SFR) in a given region being proportional to the amount of gas above a threshold density. The Central Molecular Zone (CMZ) of our Galaxy is an excellent place to test these models. It is home to the highest amount of dense, molec ...
... throughout our Galaxy as well as others, with the star formation rate (SFR) in a given region being proportional to the amount of gas above a threshold density. The Central Molecular Zone (CMZ) of our Galaxy is an excellent place to test these models. It is home to the highest amount of dense, molec ...
Black Holes and the Scientific Process
... situation presented itself about half a century ago when the very first strong X-ray emission was observed from Galactic sources. The paradigm of black holes, neutron stars (and also white dwarfs) in a binary system with a normal main sequence companion was hypothesized to explain the origin of the ...
... situation presented itself about half a century ago when the very first strong X-ray emission was observed from Galactic sources. The paradigm of black holes, neutron stars (and also white dwarfs) in a binary system with a normal main sequence companion was hypothesized to explain the origin of the ...
ppt - WISH
... z > 1.5 represents a key period where such structures are collapsing and attaining virial equilibrium optical-IR searches + photo-z will detect clusters - but a lot of filaments, LSS and projections as well X-ray plus SZ turns this into an opportunity: we can identify virial and non-virial structure ...
... z > 1.5 represents a key period where such structures are collapsing and attaining virial equilibrium optical-IR searches + photo-z will detect clusters - but a lot of filaments, LSS and projections as well X-ray plus SZ turns this into an opportunity: we can identify virial and non-virial structure ...
THE SUN - University of Mass Lowell, Space Science Laboratory
... markedly during periods of solar activity, and this causes some of the most ...
... markedly during periods of solar activity, and this causes some of the most ...
white dwarf
... • Infalling material is forced to follow the magnetic field lines • Gas is initially in free-fall but then it encounters a shock front • Shock converts kinetic energy into thermal energy (bulk motion into random motion) temperature increases to ~50 keV • Velocity drops by 1/4 and density increases ...
... • Infalling material is forced to follow the magnetic field lines • Gas is initially in free-fall but then it encounters a shock front • Shock converts kinetic energy into thermal energy (bulk motion into random motion) temperature increases to ~50 keV • Velocity drops by 1/4 and density increases ...
The impact of X-rays on molecular cloud fragmentation and the IMF
... the impact of X-rays. Simulation B has a cloud near an inactive black hole and has isothermal conditions, with an equation of state of the form P ∝ ρ. The XDR code that updates the thermodynamics is only linked with simulation A where we do have Xrays. The 107 M¯ black hole, at 10% of Eddington, yie ...
... the impact of X-rays. Simulation B has a cloud near an inactive black hole and has isothermal conditions, with an equation of state of the form P ∝ ρ. The XDR code that updates the thermodynamics is only linked with simulation A where we do have Xrays. The 107 M¯ black hole, at 10% of Eddington, yie ...
050802CWUhighSchoolStudents
... “matter tells space how to curve” “Space tells matter how to move” This looks to us like gravity General relativity predicts 43 arc sec. of perihelion shift for Mercury due to the curvature of spacetime near the sun. ...
... “matter tells space how to curve” “Space tells matter how to move” This looks to us like gravity General relativity predicts 43 arc sec. of perihelion shift for Mercury due to the curvature of spacetime near the sun. ...
The Distance Ladder I - Sierra College Astronomy Home Page
... Stars are in a state of balance, where the (inward) force of gravity is balanced by the (outward) force produced by pressure differences— the deeper into a star you go, the higher the pressure. If a star collapsed inwards upon itself (for fictional reasons), it would convert gravitational collapse e ...
... Stars are in a state of balance, where the (inward) force of gravity is balanced by the (outward) force produced by pressure differences— the deeper into a star you go, the higher the pressure. If a star collapsed inwards upon itself (for fictional reasons), it would convert gravitational collapse e ...
Non-Thermal Radio Emission from Binary Systems
... Weak-lined (WTT): non-thermal radio emission from magnetically active regions ...
... Weak-lined (WTT): non-thermal radio emission from magnetically active regions ...
Solution key
... approximately 10 Billion Years / 22.3 = 2 Billion years. This is close enough to Fig. 16-8B which says 0.9 Billion years. d. (1 point) Which image (A through F) best represents this HR diagram? ...
... approximately 10 Billion Years / 22.3 = 2 Billion years. This is close enough to Fig. 16-8B which says 0.9 Billion years. d. (1 point) Which image (A through F) best represents this HR diagram? ...
Globular Cluster Formation in CDM Cosmologies
... devoid of metals, dust, strong B field,… Going back in time – to 400 million years after the Big Bang – to the “dark era” In what kind of objects did such stars form, and how did they influence their environment… ...
... devoid of metals, dust, strong B field,… Going back in time – to 400 million years after the Big Bang – to the “dark era” In what kind of objects did such stars form, and how did they influence their environment… ...
Pulsars
... by Baade & Zwicky in 1934: "With all reserve we advance the view that a supernova represents the transition of an ordinary star into a new form of star, the neutron star, which would be the end point of stellar evolution. Such a star may possess a very small radius and an extremely high density." Pu ...
... by Baade & Zwicky in 1934: "With all reserve we advance the view that a supernova represents the transition of an ordinary star into a new form of star, the neutron star, which would be the end point of stellar evolution. Such a star may possess a very small radius and an extremely high density." Pu ...
Lectures 12 & 13 powerpoint (stellar death)
... into smaller nuclei, and the A: As the matter falls inward, it creates a degenerate electrons that shockwave that travels outward. supported the core are This shockwave is aided by two additional removed core contracts sources of energy; 2. T so high that the average 1. The disrupted nuclei in the ...
... into smaller nuclei, and the A: As the matter falls inward, it creates a degenerate electrons that shockwave that travels outward. supported the core are This shockwave is aided by two additional removed core contracts sources of energy; 2. T so high that the average 1. The disrupted nuclei in the ...
High Resolution Chandra Spectroscopy of Gamma Cassiopeia (B0
... binary system (see Harmanec et al. 2000; Miroshnichenko, Bjorkman, & Krugov 2002), the wide separation (P ≈ 204 days, with low to moderate eccentricity) makes it difficult to understand the high Lx if the companion were a white dwarf. Moreover, for a companion to have evolved to a degenerate star, i ...
... binary system (see Harmanec et al. 2000; Miroshnichenko, Bjorkman, & Krugov 2002), the wide separation (P ≈ 204 days, with low to moderate eccentricity) makes it difficult to understand the high Lx if the companion were a white dwarf. Moreover, for a companion to have evolved to a degenerate star, i ...
solar.gmu.edu
... •A quasar’s luminosity can be calculated from its apparent brightness and the distance using the inverse-square law •Even though small, the luminosity of a quasar (1038 to 1042 Watts) can be very larger, i.e., several thousand times more than the entire Milly Way Galaxies (1037). •A quasar has emiss ...
... •A quasar’s luminosity can be calculated from its apparent brightness and the distance using the inverse-square law •Even though small, the luminosity of a quasar (1038 to 1042 Watts) can be very larger, i.e., several thousand times more than the entire Milly Way Galaxies (1037). •A quasar has emiss ...
Core Collapse Supernovae and Neutron Star Kicks, a Primer David
... Core collapse supernovae represent the last stages in the life of high mass stars. Stars above the Chandrasekhar limit of ~1.4 solar masses will undergo a supernova once nuclear burning at their core can no longer support the mass of the star from gravitational collapse (Slide 2 shows the life cycle ...
... Core collapse supernovae represent the last stages in the life of high mass stars. Stars above the Chandrasekhar limit of ~1.4 solar masses will undergo a supernova once nuclear burning at their core can no longer support the mass of the star from gravitational collapse (Slide 2 shows the life cycle ...
How we know black holes exist
... theory is that as a supermassive black hole’s gravity distorts space-time nearby, it also twists its magnetic field. So when material spirals into the black hole, magnetic field lines funnel radiation and matter into regions perpendicular to the disk. This creates high-speed jets. For decades, scien ...
... theory is that as a supermassive black hole’s gravity distorts space-time nearby, it also twists its magnetic field. So when material spirals into the black hole, magnetic field lines funnel radiation and matter into regions perpendicular to the disk. This creates high-speed jets. For decades, scien ...
Lecture 24
... “Active galactic nucleus” Bright X-ray source Find signature of a gas disk in X-ray spectrum This disk is orbiting something at 30% speed of light! Also see strong “gravitational redshifts” Strong evidence for a very massive black hole in this object. ...
... “Active galactic nucleus” Bright X-ray source Find signature of a gas disk in X-ray spectrum This disk is orbiting something at 30% speed of light! Also see strong “gravitational redshifts” Strong evidence for a very massive black hole in this object. ...
Lecture 12
... We will see in next lectures what the implications of this are for other phenomena in the Universe. It actually led to the discovery of dark energy! The collapse of massive stars produces two types of remnants - neutron stars and black holes. Their masses have been measured in X-ray emitting binary ...
... We will see in next lectures what the implications of this are for other phenomena in the Universe. It actually led to the discovery of dark energy! The collapse of massive stars produces two types of remnants - neutron stars and black holes. Their masses have been measured in X-ray emitting binary ...
The Herschel view on the dust properties of the Large Magellanic
... • Motivations. The electromagnetic emission from a galaxy contains information about the physical conditions therein experienced. In star forming regions, most of the power is reradiated by dust, in the infrared. The knowledge of the grain properties (their abundance, chemical composition and size d ...
... • Motivations. The electromagnetic emission from a galaxy contains information about the physical conditions therein experienced. In star forming regions, most of the power is reradiated by dust, in the infrared. The knowledge of the grain properties (their abundance, chemical composition and size d ...
Neutron Stars - Lick Observatory
... matter density at # ! 2 × 1014 g cm!3, where the transition to a spatially uniform state occurs which is believed to be a superfluid (see figure 2). In the core of neutron stars many other problems arise. The basic difficulty in predicting neutron star properties is that matter at supernuclear densi ...
... matter density at # ! 2 × 1014 g cm!3, where the transition to a spatially uniform state occurs which is believed to be a superfluid (see figure 2). In the core of neutron stars many other problems arise. The basic difficulty in predicting neutron star properties is that matter at supernuclear densi ...
N j
... the GOODS area by fitting the luminosity functions using Markov-Chain Monte Carlo simulations. We are expanding on this technique to include uncertainties in the redshifts (often photometric) and uncertainties in the spectral energy distributions of the sources. Future work will also include perform ...
... the GOODS area by fitting the luminosity functions using Markov-Chain Monte Carlo simulations. We are expanding on this technique to include uncertainties in the redshifts (often photometric) and uncertainties in the spectral energy distributions of the sources. Future work will also include perform ...
Today in Astronomy 102: black hole observations, v.2
... that lie within the central few light years of the Galaxy: Doppler shifts in the spectra of gas clouds. Doppler shifts in the spectra of stars. Proper motions of stars (motion across the sky). From the orbital-motion velocities, one can calculate the mass lying inside each orbit, in much the s ...
... that lie within the central few light years of the Galaxy: Doppler shifts in the spectra of gas clouds. Doppler shifts in the spectra of stars. Proper motions of stars (motion across the sky). From the orbital-motion velocities, one can calculate the mass lying inside each orbit, in much the s ...
Astrophysical X-ray source
Astrophysical X-ray sources are astronomical objects with physical properties which result in the emission of X-rays.There are a number of types of astrophysical objects which emit X-rays, from galaxy clusters, through black holes in active galactic nuclei (AGN) to galactic objects such as supernova remnants, stars, and binary stars containing a white dwarf (cataclysmic variable stars and super soft X-ray sources), neutron star or black hole (X-ray binaries). Some solar system bodies emit X-rays, the most notable being the Moon, although most of the X-ray brightness of the Moon arises from reflected solar X-rays. A combination of many unresolved X-ray sources is thought to produce the observed X-ray background. The X-ray continuum can arise from bremsstrahlung, either magnetic or ordinary Coulomb, black-body radiation, synchrotron radiation, inverse Compton scattering of lower-energy photons be relativistic electrons, knock-on collisions of fast protons with atomic electrons, and atomic recombination, with or without additional electron transitions.Furthermore, celestial entities in space are discussed as celestial X-ray sources. The origin of all observed astronomical X-ray sources is in, near to, or associated with a coronal cloud or gas at coronal cloud temperatures for however long or brief a period.