Week 9 notes
... – Most stars appear to be REDDER than they really are (cooler) – Stars of a given luminosity appear FAINTER than you would calculate given their distance and the inverse square law. ...
... – Most stars appear to be REDDER than they really are (cooler) – Stars of a given luminosity appear FAINTER than you would calculate given their distance and the inverse square law. ...
Astrophysics Presentation
... It is found that there is a simple massluminosity relationship for main sequence stars The luminosity increases with the cube of the mass (this is consistent with other clues about the size, density and mass) – big is brighter (much!) Big bright stars are burning ferociously and don’t last long! Thi ...
... It is found that there is a simple massluminosity relationship for main sequence stars The luminosity increases with the cube of the mass (this is consistent with other clues about the size, density and mass) – big is brighter (much!) Big bright stars are burning ferociously and don’t last long! Thi ...
Teacher Sheet 1. What variables does the HR Diagram compare
... 14. Describe stars A, B, C, and D in terms of their brightness and temperature. Star A is red and therefore, cool. Its luminosity is 1/1000 of that of the sun; therefore, it is dim. Star B is a hot, blue star and very luminous. Both A and B are on the Main Sequence. Star C is also a hot, blue star. ...
... 14. Describe stars A, B, C, and D in terms of their brightness and temperature. Star A is red and therefore, cool. Its luminosity is 1/1000 of that of the sun; therefore, it is dim. Star B is a hot, blue star and very luminous. Both A and B are on the Main Sequence. Star C is also a hot, blue star. ...
Chapter 10 Measuring the Stars: Giants, Dwarfs, and the Main
... Luminosity and Apparent Brightness * Apparent Magnitude • Magnitude scale - ranks naked eye stars in 6 categories as originally defined by Hipparchus ...
... Luminosity and Apparent Brightness * Apparent Magnitude • Magnitude scale - ranks naked eye stars in 6 categories as originally defined by Hipparchus ...
Background Information - Eu-Hou
... In the early 20th century, after investigating the effects of an object’s temperature and of the colour of its radiation, scientists reasoned that there should be a relationship between the temperature of a star and its luminosity. If all stars were alike, those with the same luminosity would have e ...
... In the early 20th century, after investigating the effects of an object’s temperature and of the colour of its radiation, scientists reasoned that there should be a relationship between the temperature of a star and its luminosity. If all stars were alike, those with the same luminosity would have e ...
Equivalent Widths and Chemical abundances Equivalent
... the “solar nebula”, i.e. the composition of the gas cloud out of which the sun and solar system formed. That is because we can get the most detailed and precise information about this cloud from spectral analysis of the Sun and from chemical analysis of the most primitive meteorites (Carbonaceous Ch ...
... the “solar nebula”, i.e. the composition of the gas cloud out of which the sun and solar system formed. That is because we can get the most detailed and precise information about this cloud from spectral analysis of the Sun and from chemical analysis of the most primitive meteorites (Carbonaceous Ch ...
Lec7_2D
... Astronomers originally classified the spectra of stars A through O based on the amount of hydrogen absorption. But since hydrogen absorption is strongest at intermediate temperatures, this sequence was wrong! ...
... Astronomers originally classified the spectra of stars A through O based on the amount of hydrogen absorption. But since hydrogen absorption is strongest at intermediate temperatures, this sequence was wrong! ...
Document
... Please indicate the best answer to the following question on the answer sheet provided. 1. Of all the stars that are currently on the main sequence, which spectral type would be least abundant? a. A, b. B, c. K, d. M 2. What mechanism is responsible for the twisting of the Sun's magnetic filed lines ...
... Please indicate the best answer to the following question on the answer sheet provided. 1. Of all the stars that are currently on the main sequence, which spectral type would be least abundant? a. A, b. B, c. K, d. M 2. What mechanism is responsible for the twisting of the Sun's magnetic filed lines ...
Classifying Stars - Concord Academy Boyne
... Click on the picture above to watch a video from the history channel on the life cycle of a star! Quit ...
... Click on the picture above to watch a video from the history channel on the life cycle of a star! Quit ...
Study Guide: Unit 1, The Universe and its Stars, HS
... A) chemical burning B) nuclear fission C) potential energy ...
... A) chemical burning B) nuclear fission C) potential energy ...
The Life Cycle of Stars Webquest
... http://www.seasky.org/cosmic/sky7a01.html and answer the following questions: 1. Stars begin their lives as clouds of dust and gas called. 2. What is a protostar? ...
... http://www.seasky.org/cosmic/sky7a01.html and answer the following questions: 1. Stars begin their lives as clouds of dust and gas called. 2. What is a protostar? ...
The Life Cycle of Stars Webquest
... http://www.seasky.org/cosmic/sky7a01.html and answer the following questions: 1. Stars begin their lives as clouds of dust and gas called. 2. What is a protostar? ...
... http://www.seasky.org/cosmic/sky7a01.html and answer the following questions: 1. Stars begin their lives as clouds of dust and gas called. 2. What is a protostar? ...
Mr. Scharff
... Wksht. Stars and the Hertzsprung-Russell Diagram Directions. Review the Hertzsprung-Russell diagram in Chapter 26, Exploring the Universe, on Mr. Scharff’s website. Introduction. The Hertzsprung-Russell diagram is actually a graph that illustrates the relationship that exists between the average sur ...
... Wksht. Stars and the Hertzsprung-Russell Diagram Directions. Review the Hertzsprung-Russell diagram in Chapter 26, Exploring the Universe, on Mr. Scharff’s website. Introduction. The Hertzsprung-Russell diagram is actually a graph that illustrates the relationship that exists between the average sur ...
Stars PowerPoint Slides
... spectrum or matching continuous spectrum to that of a blackbody –Assume radiate somewhat like blackbodies (Planck curve) ...
... spectrum or matching continuous spectrum to that of a blackbody –Assume radiate somewhat like blackbodies (Planck curve) ...
Stellar Evolution: After the Main Sequence
... • The duration of a star’s main sequence lifetime depends on the amount of hydrogen in the star’s core and the rate at which the hydrogen is consumed • The more massive a star, the shorter is its mainsequence lifetime ...
... • The duration of a star’s main sequence lifetime depends on the amount of hydrogen in the star’s core and the rate at which the hydrogen is consumed • The more massive a star, the shorter is its mainsequence lifetime ...
The Future Sun • Homework 5 is due Wed, 24 March at 6:30am
... Not all fainter stars were observed. ...
... Not all fainter stars were observed. ...
Stars
... • If the remaining mass of the star is about 1.4 times that of our Sun, the core is unable to support itself and it will collapse further to become a neutron star • Neutron star = star remnant that results from collapse of a massive star after a ...
... • If the remaining mass of the star is about 1.4 times that of our Sun, the core is unable to support itself and it will collapse further to become a neutron star • Neutron star = star remnant that results from collapse of a massive star after a ...
Astronomy Universe2
... What is a Main Sequence Star? • The H-R diagram represents a pattern that was discovered that allows stars to be compared by brightness and color. • The majority of stars are found in a band stretching diagonally across the diagram called the “Main Sequence”. • Stars start out in the Main Sequence ...
... What is a Main Sequence Star? • The H-R diagram represents a pattern that was discovered that allows stars to be compared by brightness and color. • The majority of stars are found in a band stretching diagonally across the diagram called the “Main Sequence”. • Stars start out in the Main Sequence ...
Stars
... d. their size. ______ 18. Stars are now classified by a. their elements. b. their temperature. c. their age. d. their size. ______ 19. Class O stars, the hottest stars, are a. yellow. b. orange. c. red. d. blue. 20. Early astronomers called the brightest stars in the sky ...
... d. their size. ______ 18. Stars are now classified by a. their elements. b. their temperature. c. their age. d. their size. ______ 19. Class O stars, the hottest stars, are a. yellow. b. orange. c. red. d. blue. 20. Early astronomers called the brightest stars in the sky ...
Lifetimes of stars
... Stellar Lifetimes • The Sun (and all stars) will eventually run out of fuel (hydrogen in regions where it is hot enough for fusion). • If all the hydrogen in the Sun could fuse to helium, the Sun’s lifetime would be 100 billion years. • But, by the time about 10% of the Sun’s H has been converted in ...
... Stellar Lifetimes • The Sun (and all stars) will eventually run out of fuel (hydrogen in regions where it is hot enough for fusion). • If all the hydrogen in the Sun could fuse to helium, the Sun’s lifetime would be 100 billion years. • But, by the time about 10% of the Sun’s H has been converted in ...
AST 207 Test 2 Answers 20 October 2010
... star A. Prof. Adams says he discovered a new type of star that is fainter than white dwarfs. Has he discovered a new type of star? Explain. The clues are very much like Walter Adams’ discovery that Sirius B is a white dwarf. However, there is a crucial missing clue. Since Sirius A and B were known t ...
... star A. Prof. Adams says he discovered a new type of star that is fainter than white dwarfs. Has he discovered a new type of star? Explain. The clues are very much like Walter Adams’ discovery that Sirius B is a white dwarf. However, there is a crucial missing clue. Since Sirius A and B were known t ...
1 Ay 124 Winter 2014 – HOMEWORK #2 Problem 1
... a) Find the slope x such that an observer in a homogeneous, isotropic region counts, at every apparent bolmetric magnitude, equal numbers of stars in each octave of luminosity. What type of star dominates the counts if x is flatter than this critical value? b) Find the slope x such that an observer ...
... a) Find the slope x such that an observer in a homogeneous, isotropic region counts, at every apparent bolmetric magnitude, equal numbers of stars in each octave of luminosity. What type of star dominates the counts if x is flatter than this critical value? b) Find the slope x such that an observer ...
Stellar classification
In astronomy, stellar classification is the classification of stars based on their spectral characteristics. Light from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting the rainbow of colors interspersed with absorption lines. Each line indicates an ion of a certain chemical element, with the line strength indicating the abundance of that ion. The relative abundance of the different ions varies with the temperature of the photosphere. The spectral class of a star is a short code summarizing the ionization state, giving an objective measure of the photosphere's temperature and density.Most stars are currently classified under the Morgan–Keenan (MK) system using the letters O, B, A, F, G, K, and M, a sequence from the hottest (O type) to the coolest (M type). Each letter class is then subdivided using a numeric digit with 0 being hottest and 9 being coolest (e.g. A8, A9, F0, F1 form a sequence from hotter to cooler). The sequence has been expanded with classes for other stars and star-like objects that do not fit in the classical system, such class D for white dwarfs and class C for carbon stars.In the MK system a luminosity class is added to the spectral class using Roman numerals. This is based on the width of certain absorption lines in the star's spectrum which vary with the density of the atmosphere and so distinguish giant stars from dwarfs. Luminosity class 0 or Ia+ stars for hypergiants, class I stars for supergiants, class II for bright giants, class III for regular giants, class IV for sub-giants, class V for main-sequence stars, class sd for sub-dwarfs, and class D for white dwarfs. The full spectral class for the Sun is then G2V, indicating a main-sequence star with a temperature around 5,800K.