Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
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Textbook Question
Chapter 19, Problem 16E
Figure 19.9 is the light curve for the prototype cepheid variable Delta Cephei. How does the luminosity of this star compare with that of the Sun?
Figure 19.9 Cepheid Light Curve. This light curve shows how the brightness changes with time for a typical cepheid variable, with a period of about 6 days.
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The mass-luminosity relation describes the mathematical relationship between luminosity and mass for main sequence stars. It describes how a star with a mass of 4 M⊙ would have a luminosity of ______ L⊙.
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Please answer question 13 thank you.
Chapter 19 Solutions
Astronomy
Ch. 19 - Explain how parallax measurements can be used to...Ch. 19 - Suppose you have discovered a new cepheid variable...Ch. 19 - Explain how you would use the spectrum of a star...Ch. 19 - Which method would you use to obtain the distance...Ch. 19 - What are the luminosity class and spectral type of...Ch. 19 - The meter was redefined as a reference to Earth,...Ch. 19 - While a meter is the fundamental unit of length,...Ch. 19 - Most distances in the Galaxy are measured in...Ch. 19 - The AU is defined as the average distance between...Ch. 19 - What would be the advantage of making parallax...
Ch. 19 - Parallaxes are measured in fractions of an...Ch. 19 - For centuries, astronomers wondered whether comets...Ch. 19 - The Sun is much closer to Earth than are the...Ch. 19 - Parallaxes of stars are sometimes measured...Ch. 19 - Estimating the luminosity class of an M star is...Ch. 19 - Figure 19.9 is the light curve for the prototype...Ch. 19 - Which of the following can you determine about a...Ch. 19 - A G2 star has a luminosity 100 times that of the...Ch. 19 - A star has a temperature of 10,000 K and a...Ch. 19 - What is the advantage of measuring a parallax...Ch. 19 - What is the disadvantage of the parallax method,...Ch. 19 - Luhman 16 and WISE 0720 are brown dwarfs, also...Ch. 19 - Most stars close to the Sun are red dwarfs. What...Ch. 19 - Why would it be easier to measure the...Ch. 19 - When Henrietta Leavitt discovered the...Ch. 19 - A radar astronomer who is new at the job claims...Ch. 19 - The New Horizons probe flew past Pluto in July...Ch. 19 - Estimate the maximum and minimum time it takes a...Ch. 19 - The Apollo program (not the lunar missions with...Ch. 19 - In 1974, the Arecibo Radio telescope in Puerto...Ch. 19 - Demonstrate that 1 pc equals 3.091013 k m and that...Ch. 19 - The best parallaxes obtained with Hipparcos have...Ch. 19 - Astronomers are always making comparisons between...Ch. 19 - Gaia will have greatly improved precision over the...Ch. 19 - Using the same techniques as used in Exercise...Ch. 19 - The human eye is capable of an angular resolution...Ch. 19 - How much better is the resolution of the Gaia...Ch. 19 - The most recently discovered system close to Earth...Ch. 19 - What would the parallax of Luhman 16 (see Exercise...Ch. 19 - The New Horizons probe that passed by Pluto during...Ch. 19 - What physical properties are different for an M...
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