5.1 Introduction and Definitions
... κes is also a source of continuum opacity. Its value is very small, σT = 6.7 × 10−25 cm2 , some seven orders of magnitude smaller, for example, that the cross-section for photoionisation of neutral hydrogen from the ground state, σ0 = 6.3 × 10−18 cm2 . Thus, Thomson scattering is important only when ...
... κes is also a source of continuum opacity. Its value is very small, σT = 6.7 × 10−25 cm2 , some seven orders of magnitude smaller, for example, that the cross-section for photoionisation of neutral hydrogen from the ground state, σ0 = 6.3 × 10−18 cm2 . Thus, Thomson scattering is important only when ...
Stars: Their Life and Afterlife
... stars. Star formation in any size of cloud requires that cold, dense regions develop – the initial formation of these regions can be triggered by turbulence and motion generated in the rotation of the galactic spiral arms, or by more local events like compression of gas by a nearby supernova remnant ...
... stars. Star formation in any size of cloud requires that cold, dense regions develop – the initial formation of these regions can be triggered by turbulence and motion generated in the rotation of the galactic spiral arms, or by more local events like compression of gas by a nearby supernova remnant ...
Powerpoint of lecture 16
... • Star evolves on thermal timescale of core • Higher-mass stars: L roughly constant (Hertzsprung gap) • Lower-mass stars: L increases, Teff still decreases • When star reaches Hayashi line, it can’t cross it into ‘forbidden region’ • Again need improved surface boundary conditions • Star develops de ...
... • Star evolves on thermal timescale of core • Higher-mass stars: L roughly constant (Hertzsprung gap) • Lower-mass stars: L increases, Teff still decreases • When star reaches Hayashi line, it can’t cross it into ‘forbidden region’ • Again need improved surface boundary conditions • Star develops de ...
Characteristics of Stars
... imagined that groups of stars formed pictures of people or animals. Today, we call these imaginary patterns of stars constellations. Astronomers classify stars according to their physical characteristics. Characteristics used to classify stars include color, temperature, size, composition, and brigh ...
... imagined that groups of stars formed pictures of people or animals. Today, we call these imaginary patterns of stars constellations. Astronomers classify stars according to their physical characteristics. Characteristics used to classify stars include color, temperature, size, composition, and brigh ...
insert - Athens
... medium-sized star like our sun could hold more than a million earths inside it! Other stars such as supergiants may be thousands of times larger than our sun. But the enormous distance between them and our earth makes tham appear tiny in the night sky. So what makes a star shine? Hot gases under eno ...
... medium-sized star like our sun could hold more than a million earths inside it! Other stars such as supergiants may be thousands of times larger than our sun. But the enormous distance between them and our earth makes tham appear tiny in the night sky. So what makes a star shine? Hot gases under eno ...
Variable Stars as Essential Astrophysical Tools
... Surveys of new variable stars Locate detached and semi-detached eclipsing binaries in clusters1 Locate contact eclipsing binaries in clusters2 Period/amplitude variations in contact systems3 Period-to-period variability in long period variables Search for cataclysmic variables in clusters4 Search fo ...
... Surveys of new variable stars Locate detached and semi-detached eclipsing binaries in clusters1 Locate contact eclipsing binaries in clusters2 Period/amplitude variations in contact systems3 Period-to-period variability in long period variables Search for cataclysmic variables in clusters4 Search fo ...
Stars off the Main Sequence - ScienceEducationatNewPaltz
... Red Dwarf Stars Continued Can conserve their fuel for much longer than other stars Some red dwarf stars will burn for up to 10 trillion years The smallest red dwarfs are 0.075 times the mass of the Sun and largest up to ½ our Sun ...
... Red Dwarf Stars Continued Can conserve their fuel for much longer than other stars Some red dwarf stars will burn for up to 10 trillion years The smallest red dwarfs are 0.075 times the mass of the Sun and largest up to ½ our Sun ...
Answers
... stars with different starting masses. ☆ Select a different starting mass for your star in the ‘Star Properties’ banner. ☆ Use the Hertzsprung-Russell diagram tab, click play to watch your new stars evolution. ☆ Try out a few different masses then answer the following questions. 1. Using the Hertzspr ...
... stars with different starting masses. ☆ Select a different starting mass for your star in the ‘Star Properties’ banner. ☆ Use the Hertzsprung-Russell diagram tab, click play to watch your new stars evolution. ☆ Try out a few different masses then answer the following questions. 1. Using the Hertzspr ...
ASTRONOMY 120
... As a dying star sheds its outer layers to make a planetary nebula, the dead core of the star is exposed. In the case of a solar-mass star, this core will be made of carbon. The core stabilizes at a radius roughly equal to that of the Earth. This means it has an incredibly high density, a million tim ...
... As a dying star sheds its outer layers to make a planetary nebula, the dead core of the star is exposed. In the case of a solar-mass star, this core will be made of carbon. The core stabilizes at a radius roughly equal to that of the Earth. This means it has an incredibly high density, a million tim ...
Chapter 12
... 1. The temperature of a star can be determined from its_____________. 2. The pattern of the absorption spectral lines for a star contains information about a star’s________________. 3. The Doppler shift of a star's spectral lines tells us something about the star’s_______________. 4. The distance of ...
... 1. The temperature of a star can be determined from its_____________. 2. The pattern of the absorption spectral lines for a star contains information about a star’s________________. 3. The Doppler shift of a star's spectral lines tells us something about the star’s_______________. 4. The distance of ...
Stellar Evolution – Life of a Star
... • He is now the fuel source, but the temperature and energy needed to ignite He fusion is greater than H. Thus, the energy released by He fusion in the core is greater than needed to support the weight of the outer layer. The excess energy expands the outer layers beyond its previous radius and star ...
... • He is now the fuel source, but the temperature and energy needed to ignite He fusion is greater than H. Thus, the energy released by He fusion in the core is greater than needed to support the weight of the outer layer. The excess energy expands the outer layers beyond its previous radius and star ...
Stars in Their Youth
... The Hertzsprung–Russell Diagram Perhaps the most important diagram in stellar astronomy is what is known as the Hertzsprung–Russell diagram (H–R diagram). It is a plot of the luminosity of a star versus its surface temperature (also known as the effective temperature). Most stars you see in the sky ...
... The Hertzsprung–Russell Diagram Perhaps the most important diagram in stellar astronomy is what is known as the Hertzsprung–Russell diagram (H–R diagram). It is a plot of the luminosity of a star versus its surface temperature (also known as the effective temperature). Most stars you see in the sky ...
The Milky Way - Houston Community College System
... strip (Main Sequence) in the Hertzsprung-Russell diagram. ...
... strip (Main Sequence) in the Hertzsprung-Russell diagram. ...
Слайд 1 - University of Wrocław
... To facilitate simulation one usually subdivides the problems artificially into two parts by analyzing heat transport in the outer heat blanketing envelope and in the interior. ...
... To facilitate simulation one usually subdivides the problems artificially into two parts by analyzing heat transport in the outer heat blanketing envelope and in the interior. ...
HR Diagram - TeacherWeb
... 3. Classify: Click Move all and then Sort stars. Click the Tools palette at lower left and click Screen shot. Right click the image, click Copy Image, and paste a screenshot of the diagram in a blank document that you will turn in with this worksheet. Circle stars that you think belong in a group to ...
... 3. Classify: Click Move all and then Sort stars. Click the Tools palette at lower left and click Screen shot. Right click the image, click Copy Image, and paste a screenshot of the diagram in a blank document that you will turn in with this worksheet. Circle stars that you think belong in a group to ...
Information (Word Doc)
... Gravity pulls the materials together. Compressing the gas and dust into a giant ball that, at it’s centre temperatures are 15 million degrees or so (created by all gas and dust bumping into each other under the great pressure of the surrounding material). The pressure at the centre of the ball becom ...
... Gravity pulls the materials together. Compressing the gas and dust into a giant ball that, at it’s centre temperatures are 15 million degrees or so (created by all gas and dust bumping into each other under the great pressure of the surrounding material). The pressure at the centre of the ball becom ...
Gizmos: H-R Diagrams
... Gizmo Warm-up In the early 1900s, astronomers were able to identify many star characteristics such as color, size, temperature, and luminosity—or how bright a star is. However, astronomers did not yet understand exactly how these characteristics were related. Using the H-R Diagram Gizmo™, you will d ...
... Gizmo Warm-up In the early 1900s, astronomers were able to identify many star characteristics such as color, size, temperature, and luminosity—or how bright a star is. However, astronomers did not yet understand exactly how these characteristics were related. Using the H-R Diagram Gizmo™, you will d ...
Astronomy Assignment #1
... collapsing core is pushed deeper into the star as the core collapses and can now fuse for the first time. Shell Hburning begins. The shell H-burning releases gamma rays that do not have to thermalize out of the core so they hit the envelope with more energy that core gamma rays would and, in effect, ...
... collapsing core is pushed deeper into the star as the core collapses and can now fuse for the first time. Shell Hburning begins. The shell H-burning releases gamma rays that do not have to thermalize out of the core so they hit the envelope with more energy that core gamma rays would and, in effect, ...
Stellar Deaths - Mid
... - Low mass star (< 8 Msun) cannot achieve 600 Million K temp. needed for Carbon fusion ...
... - Low mass star (< 8 Msun) cannot achieve 600 Million K temp. needed for Carbon fusion ...
Spectra of Star Clusters
... spectral types are O, B, A, F, G, K, and M. These are subdivided into numbered categories; for example, the hottest A stars are type A0 and the coolest A stars are type A9, which is slightly ...
... spectral types are O, B, A, F, G, K, and M. These are subdivided into numbered categories; for example, the hottest A stars are type A0 and the coolest A stars are type A9, which is slightly ...