CHAPTER 1 The Formation and Structure of Stars
... • The stability of a star depends on the relation between gas pressure and temperature. • Nuclear fusion at the centers of stars heats their interiors, creates high gas pressures, and thus balances the inward forces of gravity. – If an increase or decrease in temperature produces a corresponding cha ...
... • The stability of a star depends on the relation between gas pressure and temperature. • Nuclear fusion at the centers of stars heats their interiors, creates high gas pressures, and thus balances the inward forces of gravity. – If an increase or decrease in temperature produces a corresponding cha ...
Chapter 13 – Behavior of Spectral Lines
... • When Hbf opacity dominates, is independent of Pe, while the line absorption coefficient is proportional to Pe, so line strength is too • In hotter stars (with electron scattering) is nearly independent of pressure while the number of neutral H atoms is proportional to Pe2. Balmer profiles ar ...
... • When Hbf opacity dominates, is independent of Pe, while the line absorption coefficient is proportional to Pe, so line strength is too • In hotter stars (with electron scattering) is nearly independent of pressure while the number of neutral H atoms is proportional to Pe2. Balmer profiles ar ...
Abstract - UChicago High Energy Physics
... where, ǫ(ρ, I) is the energy per nucleon, ρ = ρn + ρp , I = (ρn − ρp )/ρ is the asymmetry with ρn and ρp being densities for the neutrons and the protons. The ǫ(ρ, 0) is the EOS for the symmetric nuclear matter and S(ρ) is the symmetry energy coefficient at a density ρ. The EOS of the symmetric nucl ...
... where, ǫ(ρ, I) is the energy per nucleon, ρ = ρn + ρp , I = (ρn − ρp )/ρ is the asymmetry with ρn and ρp being densities for the neutrons and the protons. The ǫ(ρ, 0) is the EOS for the symmetric nuclear matter and S(ρ) is the symmetry energy coefficient at a density ρ. The EOS of the symmetric nucl ...
Constellation Classification Cards*
... and appears that way in both sets. Use the first number for Albireo when forming the graph. Albireo is a beautiful double star (the stars are close to each other in the sky, but may not be orbiting each other, i.e., not a binary). 7. Students with stars less than 0 on the brightness scale should tak ...
... and appears that way in both sets. Use the first number for Albireo when forming the graph. Albireo is a beautiful double star (the stars are close to each other in the sky, but may not be orbiting each other, i.e., not a binary). 7. Students with stars less than 0 on the brightness scale should tak ...
Debris disks: dynamics of small particles in
... with a radius ~55 AU, and a dust mass 5 x 10-4 Mearth • Thus it has at least ten times more mass than the Kuiper Belt ~10-5 Mearth • The only solar-type (age and spectral type) star with confirmed debris disk 850 μm ...
... with a radius ~55 AU, and a dust mass 5 x 10-4 Mearth • Thus it has at least ten times more mass than the Kuiper Belt ~10-5 Mearth • The only solar-type (age and spectral type) star with confirmed debris disk 850 μm ...
analysis of eclipsing binary data - Astrophysics
... determination exercise, but the recommended epoch must be used for the preparation of light and radial velocity curves to be submitted for marking. It is suggested that a wide period range be selected initially, with a period increment chosen so that something like ten or twenty periods will be trie ...
... determination exercise, but the recommended epoch must be used for the preparation of light and radial velocity curves to be submitted for marking. It is suggested that a wide period range be selected initially, with a period increment chosen so that something like ten or twenty periods will be trie ...
11 The Interstellar Medium
... sequence and will remain there as long as it has hydrogen to fuse in its core. ...
... sequence and will remain there as long as it has hydrogen to fuse in its core. ...
EQUINOCTIAL vLOBE ·
... Fig. 1. Let P be the pole of the ecliptic CV" $ � vY. N the pole of the equator CV" �, cutting the ecliptic in
... Fig. 1. Let P be the pole of the ecliptic CV" $ � vY. N the pole of the equator CV" �, cutting the ecliptic in
FREE Sample Here
... and set the magnitude limit to -30.0 to 5.0 and turn off the display of all objects except stars, planets, moon, and sun. For now turn off all reference lines, including the constellation reference lines. Now you’re ready to begin the demonstration. Press Alt+> and the program will display the daily ...
... and set the magnitude limit to -30.0 to 5.0 and turn off the display of all objects except stars, planets, moon, and sun. For now turn off all reference lines, including the constellation reference lines. Now you’re ready to begin the demonstration. Press Alt+> and the program will display the daily ...
Video Lesson Information Astronomy: Observations & Theories Astronomy 1
... Saturn’s interior and atmosphere are compared with those of Jupiter. The formation and characteristics of the ice giants Uranus and Neptune are also discussed. Lesson 19 - Solar System Debris This examination of solar system “debris”: meteorites, asteroids, and comets concludes the exploration of th ...
... Saturn’s interior and atmosphere are compared with those of Jupiter. The formation and characteristics of the ice giants Uranus and Neptune are also discussed. Lesson 19 - Solar System Debris This examination of solar system “debris”: meteorites, asteroids, and comets concludes the exploration of th ...
chapter 2 - Test Bank 1
... and set the magnitude limit to -30.0 to 5.0 and turn off the display of all objects except stars, planets, moon, and sun. For now turn off all reference lines, including the constellation reference lines. Now you’re ready to begin the demonstration. Press Alt+> and the program will display the daily ...
... and set the magnitude limit to -30.0 to 5.0 and turn off the display of all objects except stars, planets, moon, and sun. For now turn off all reference lines, including the constellation reference lines. Now you’re ready to begin the demonstration. Press Alt+> and the program will display the daily ...
Doppler imaging of stellar surfaces
... been from the application of Doppler imaging (DI). Radio long-baseline interferometry may give us milliarcsecond resolution but Doppler imaging can reach an effective resolution several orders of magnitude better than that. The application of DI over the last decade has produced images of many stars ...
... been from the application of Doppler imaging (DI). Radio long-baseline interferometry may give us milliarcsecond resolution but Doppler imaging can reach an effective resolution several orders of magnitude better than that. The application of DI over the last decade has produced images of many stars ...
Notable long-period eclipsing binaries. Part I. - Project VS
... Long-period eclipsing binary stars are very important for stellar astrophysicists, because they offer the chance to study the characteristics of isolated stars with a high degree of precision and accuracy. The most interesting fact about eclipsing binaries is that all kinds of stars are found as mem ...
... Long-period eclipsing binary stars are very important for stellar astrophysicists, because they offer the chance to study the characteristics of isolated stars with a high degree of precision and accuracy. The most interesting fact about eclipsing binaries is that all kinds of stars are found as mem ...
Lecture 12: Evolution of the Galaxy
... heavy element mass fraction, Z, at the time of their birth. The youngest stars are therefore the most heavy-element rich, and the oldest ones (Population II stars) are the most deficient in heavy elements relative to the Sun. • Halo Population II stars have Z ~ 10-3 to 10-1 Z⊙ • Disk Population I st ...
... heavy element mass fraction, Z, at the time of their birth. The youngest stars are therefore the most heavy-element rich, and the oldest ones (Population II stars) are the most deficient in heavy elements relative to the Sun. • Halo Population II stars have Z ~ 10-3 to 10-1 Z⊙ • Disk Population I st ...
The Galactic evolution of phosphorus
... log (EW/λ) ≤ −5.5, and a Gaussian profile is a good approximation for the line profile fitting. The P i line at 1051 nm is, for several stars, contaminated by telluric absorption (see upperleft panel of Fig. 1). When possible, we measured the EW of the P i line taking into account the presence of th ...
... log (EW/λ) ≤ −5.5, and a Gaussian profile is a good approximation for the line profile fitting. The P i line at 1051 nm is, for several stars, contaminated by telluric absorption (see upperleft panel of Fig. 1). When possible, we measured the EW of the P i line taking into account the presence of th ...
cohen_paris_v2_may2009 - Astronomy at Swarthmore College
... consistent with the predictions of the wind instability model. Photoelectric absorption’s effect on the profile shapes can be used as a mass-loss rate diagnostic: massloss rates are lower than previously thought. ...
... consistent with the predictions of the wind instability model. Photoelectric absorption’s effect on the profile shapes can be used as a mass-loss rate diagnostic: massloss rates are lower than previously thought. ...
Visual Photometry - El Camino College
... 2) List 2 or more sources of uncertainty (things that give you trouble) in performing visual photometry. For the clear night lab, list those that you gave in the cloudy night lab, if applicable here, as well as 2 (or more) new sources of error introduced by doing this experiment using a real telesco ...
... 2) List 2 or more sources of uncertainty (things that give you trouble) in performing visual photometry. For the clear night lab, list those that you gave in the cloudy night lab, if applicable here, as well as 2 (or more) new sources of error introduced by doing this experiment using a real telesco ...
Annual report 2004 - Département d`Astrophysique, Géophysique et
... period of 357.0 days. We derive for the first time the orbital parameters of the system and find a very 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 bi ...
... period of 357.0 days. We derive for the first time the orbital parameters of the system and find a very 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 bi ...
ppt - SLAC
... 2. Atmospheric pressure depends on the star's surface gravity and so, roughly, on its size —a giant, dwarf, or in between. The size and surface brightness yield the star's luminosity and often its evolutionary status (young, middle-aged, or nearing death). Apparent brightness then gives an idea of t ...
... 2. Atmospheric pressure depends on the star's surface gravity and so, roughly, on its size —a giant, dwarf, or in between. The size and surface brightness yield the star's luminosity and often its evolutionary status (young, middle-aged, or nearing death). Apparent brightness then gives an idea of t ...
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.