ppt - 2006 Mitchell Symposium
... Core collapse polarization tends to be larger at later times when see deeper in and larger when outer hydrogen envelope is less when see deeper in, both imply it is the machinery, the core collapse mechanism itself that is strongly asymmetric (Wang et al. 1996, 2001; Leonard et al. 2001). The explos ...
... Core collapse polarization tends to be larger at later times when see deeper in and larger when outer hydrogen envelope is less when see deeper in, both imply it is the machinery, the core collapse mechanism itself that is strongly asymmetric (Wang et al. 1996, 2001; Leonard et al. 2001). The explos ...
Sun: Nuclear Powerhouse - Wayne State University Physics and
... Balancing Fusion, Gravity, and Pressure If the fusion rate increases, then thermal pressure increases causing the star to expand the star expands to a new point where gravity would balance the thermal pressure the expansion would reduce the pressure inside the core the temperature in the core would ...
... Balancing Fusion, Gravity, and Pressure If the fusion rate increases, then thermal pressure increases causing the star to expand the star expands to a new point where gravity would balance the thermal pressure the expansion would reduce the pressure inside the core the temperature in the core would ...
Document
... The bigger the Star the smaller its lifespan • The most massive stars have the shortest lives. • Stars that are 25 to 50 times that of the Sun live for only a few million years. • Stars like our Sun live for about 10 billion years (our Sun is about half way through its life cycle!) • Stars less mas ...
... The bigger the Star the smaller its lifespan • The most massive stars have the shortest lives. • Stars that are 25 to 50 times that of the Sun live for only a few million years. • Stars like our Sun live for about 10 billion years (our Sun is about half way through its life cycle!) • Stars less mas ...
PH607lec12-5gal3
... the Milky Way is only about 0.25 degrees. In fact, pitch angles measured from photographs range from about 5 degrees for Sa galaxies to 20 degrees for Sc galaxies. The most likely implication is that spiral arms are not material features. First ingredient for producing spiral arms is differential ro ...
... the Milky Way is only about 0.25 degrees. In fact, pitch angles measured from photographs range from about 5 degrees for Sa galaxies to 20 degrees for Sc galaxies. The most likely implication is that spiral arms are not material features. First ingredient for producing spiral arms is differential ro ...
9 Dwarf Galaxies
... the Milky Way is only about 0.25 degrees. In fact, pitch angles measured from photographs range from about 5 degrees for Sa galaxies to 20 degrees for Sc galaxies. The most likely implication is that spiral arms are not material features. First ingredient for producing spiral arms is differential ro ...
... the Milky Way is only about 0.25 degrees. In fact, pitch angles measured from photographs range from about 5 degrees for Sa galaxies to 20 degrees for Sc galaxies. The most likely implication is that spiral arms are not material features. First ingredient for producing spiral arms is differential ro ...
PH607lec10-4gal2
... the Milky Way is only about 0.25 degrees. In fact, pitch angles measured from photographs range from about 5 degrees for Sa galaxies to 20 degrees for Sc galaxies. The most likely implication is that spiral arms are not material features. First ingredient for producing spiral arms is differential ro ...
... the Milky Way is only about 0.25 degrees. In fact, pitch angles measured from photographs range from about 5 degrees for Sa galaxies to 20 degrees for Sc galaxies. The most likely implication is that spiral arms are not material features. First ingredient for producing spiral arms is differential ro ...
using a cepheid variable to determine distance
... USING A CEPHEID VARIABLE TO DETERMINE DISTANCE ...
... USING A CEPHEID VARIABLE TO DETERMINE DISTANCE ...
Chandra Observation of Pulsar Wind Nebula
... Materials ejected by the binary system during its evolution? The mass donor is suggested to be very similar to the Sun but a slightly evolved, it can not contribute to the cloud during its lifetime. The planetary nebula surrounding the exploded white dwarf could be a source of the cloud materia ...
... Materials ejected by the binary system during its evolution? The mass donor is suggested to be very similar to the Sun but a slightly evolved, it can not contribute to the cloud during its lifetime. The planetary nebula surrounding the exploded white dwarf could be a source of the cloud materia ...
Discovery of a strong magnetic field in the rapidly rotating B2Vn star
... models from TLUSTY (Lanz & Hubeny 2007) and also the SYNSPEC line formation code.2 Effective temperatures (Teff ) from 15 000 to 22 000 K (steps of 1000 K) and surface gravities (log g) from 3.0 to 4.0 (steps of 0.25 dex) were considered to model the observed optical and UV spectra.3 The spectral ty ...
... models from TLUSTY (Lanz & Hubeny 2007) and also the SYNSPEC line formation code.2 Effective temperatures (Teff ) from 15 000 to 22 000 K (steps of 1000 K) and surface gravities (log g) from 3.0 to 4.0 (steps of 0.25 dex) were considered to model the observed optical and UV spectra.3 The spectral ty ...
Galactic Rotation
... The mean azimuthal velocity of a population of stars differs from the circular velocity due to the asymmetric drift. This offset arises because both the density of stars and the velocity dispersion typically decline with radius. This means that more stars with guiding centers at R < R0 are passing t ...
... The mean azimuthal velocity of a population of stars differs from the circular velocity due to the asymmetric drift. This offset arises because both the density of stars and the velocity dispersion typically decline with radius. This means that more stars with guiding centers at R < R0 are passing t ...
Chapter 8 – Continuous Absorption
... Free-Free Absorption from H I • Much less than bf absorption • Kramers (1923) + Gaunt (1930) again • Absorption coefficient depends on the speed of the electron (slower electrons are more likely to absorb a photon because their encounters with H atoms take longer) • Adopt a Maxwell-Boltzman distribu ...
... Free-Free Absorption from H I • Much less than bf absorption • Kramers (1923) + Gaunt (1930) again • Absorption coefficient depends on the speed of the electron (slower electrons are more likely to absorb a photon because their encounters with H atoms take longer) • Adopt a Maxwell-Boltzman distribu ...
Homework
... Warm Up-Accelerated Thursday, February 4 Are we made of “Star Stuff?” A newspaper article reported that astronomers claim people are made of stardust. What does this mean? Pick the answer that best matches what you think “being made of stardust” means. a. “Being made of stardust” is not intended to ...
... Warm Up-Accelerated Thursday, February 4 Are we made of “Star Stuff?” A newspaper article reported that astronomers claim people are made of stardust. What does this mean? Pick the answer that best matches what you think “being made of stardust” means. a. “Being made of stardust” is not intended to ...
Spiral galaxies: Spiral galaxies: Inclination Spiral galaxies: Internal
... • In denser regions of the ISM, collisions between atoms become frequent enough to form molecules. • The most common molecule is H2, but since H2 is a symmetric molecule, it has no rotational quantum transitions. It is therefore extremely difficult to detect. • As a tracer of H2, astronomers usually ...
... • In denser regions of the ISM, collisions between atoms become frequent enough to form molecules. • The most common molecule is H2, but since H2 is a symmetric molecule, it has no rotational quantum transitions. It is therefore extremely difficult to detect. • As a tracer of H2, astronomers usually ...
Star Finder
... connecting them goes almost directly to the NORTH Celestial POLE or the pole star “Polaris” III: THE SKY DURING THE SEASONS: Since the entire sky rotates through the day if you stayed up all night you would see almost all the constellations. We speak of seasonal stars as those seen before Midnight s ...
... connecting them goes almost directly to the NORTH Celestial POLE or the pole star “Polaris” III: THE SKY DURING THE SEASONS: Since the entire sky rotates through the day if you stayed up all night you would see almost all the constellations. We speak of seasonal stars as those seen before Midnight s ...
PH607lec11-4gal2
... the Milky Way is only about 0.25 degrees. In fact, pitch angles measured from photographs range from about 5 degrees for Sa galaxies to 20 degrees for Sc galaxies. The most likely implication is that spiral arms are not material features. First ingredient for producing spiral arms is differential ro ...
... the Milky Way is only about 0.25 degrees. In fact, pitch angles measured from photographs range from about 5 degrees for Sa galaxies to 20 degrees for Sc galaxies. The most likely implication is that spiral arms are not material features. First ingredient for producing spiral arms is differential ro ...
The Milky Way
... • That makes for a galactic year (circumference divided by velocity) of • (2 ) x 8,000 x (3.0857 x 1013 km) / 220 km/s = 7.1 x 1015 s = 2.24 x 108 yr. • So, roughly 225 million years is ONE GALACTIC YEAR. • How old is the solar system in galactic years? • At nearly 4.6 billion years of age, the SS ...
... • That makes for a galactic year (circumference divided by velocity) of • (2 ) x 8,000 x (3.0857 x 1013 km) / 220 km/s = 7.1 x 1015 s = 2.24 x 108 yr. • So, roughly 225 million years is ONE GALACTIC YEAR. • How old is the solar system in galactic years? • At nearly 4.6 billion years of age, the SS ...
Lec2015_22
... Structure and Evolution of Stars Lecture 22: Nucleosynthesis and Population III • Nucleosynthesis – where did the elements come from? ...
... Structure and Evolution of Stars Lecture 22: Nucleosynthesis and Population III • Nucleosynthesis – where did the elements come from? ...
Powerpoint
... • RR Lyrae stars all have about the same luminosity; knowing their apparent magnitude allows us to calculate the distance. • Cepheids have a luminosity that is strongly correlated with the period of their oscillations; once the period is measured, the luminosity is known and ...
... • RR Lyrae stars all have about the same luminosity; knowing their apparent magnitude allows us to calculate the distance. • Cepheids have a luminosity that is strongly correlated with the period of their oscillations; once the period is measured, the luminosity is known and ...
- newmanlib.ibri.org
... Because gravity is a spherically symmetric force, a star is spherical, except for a larger or smaller bulge at its equator, depending on how fast it is spinning. The force of gravity heats up the gas inside the star, until it reaches a temperature high enough to turn on a nuclear reaction by which h ...
... Because gravity is a spherically symmetric force, a star is spherical, except for a larger or smaller bulge at its equator, depending on how fast it is spinning. The force of gravity heats up the gas inside the star, until it reaches a temperature high enough to turn on a nuclear reaction by which h ...
IK Pegasi
IK Pegasi (or HR 8210) is a binary star system in the constellation Pegasus. It is just luminous enough to be seen with the unaided eye, at a distance of about 150 light years from the Solar System.The primary (IK Pegasi A) is an A-type main-sequence star that displays minor pulsations in luminosity. It is categorized as a Delta Scuti variable star and it has a periodic cycle of luminosity variation that repeats itself about 22.9 times per day. Its companion (IK Pegasi B) is a massive white dwarf—a star that has evolved past the main sequence and is no longer generating energy through nuclear fusion. They orbit each other every 21.7 days with an average separation of about 31 million kilometres, or 19 million miles, or 0.21 astronomical units (AU). This is smaller than the orbit of Mercury around the Sun.IK Pegasi B is the nearest known supernova progenitor candidate. When the primary begins to evolve into a red giant, it is expected to grow to a radius where the white dwarf can accrete matter from the expanded gaseous envelope. When the white dwarf approaches the Chandrasekhar limit of 1.44 solar masses (M☉), it may explode as a Type Ia supernova.