Universe: Stars And Galaxies
6th Edition
ISBN: 9781319115098
Author: Roger Freedman, Robert Geller, William J. Kaufmann
Publisher: W. H. Freeman
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Chapter 17, Problem 32Q
To determine
The value of B-V color index for very hot and very cold stars.
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"51 Pegasi" is the name of the first normal star (besides the Sun) around which a planet was discovered. It is in the constellation Pegasus the horse. Its parallax is measured to be 0.064 arcsec.
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(Round your answer to at least one decimal place.)
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Balmer-alpha (656.3 nm)
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Chapter 17 Solutions
Universe: Stars And Galaxies
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- As a star runs out of hydrogen to fuel nuclear fusion in its core, changes within the star usually cause it to leave the main sequence, expanding and cooling as it does so. Would a star with a radius 6 times that of the Sun, but a surface temperature 0.4 times that of the Sun, be more, or less luminous than the Sun? Show and explain your reasoning. You may assume the surface area of a sphere is A = 4πr2.arrow_forwardv Correct Part C Which has a greater luminosity, a star with absolute magnitude -2 or a star with absolute magnitude 8 ? O A star with absolute magnitude 8. A star with absolute magnitude -2. Submit Previous Answers Correct Part D By how much? LM=-2 LM-8 000000001 Submit Previous Answers Request Answer X Incorrect; Try Again; 5 attempts remaining Next > Provide Feedback P Pearson 8:58 PM (cp ツ 4/2/202 earson Education Inc. All rights reserved. | Terms of Use Privacy Policy Permissions Contact Us | 49°F Sunnyarrow_forwardThe a star system contains two stars, one with apparent magnitude m = 10.5 and the other with m = 10.9. What is the combined apparent magnitude of the two stars?arrow_forward
- L = ( 0.0813 ) x (Rs) ^2 x 10-0.4m x Ls where L = luminosity of the desired star Rs = distance of the stars in light years m = apparent magnitude of star Ls = Luminosity of Sun = 1.00 The calculated value of Polaris' luminosity is: a. 2382 times Ls b. 6040 times Ls c. 5566 times Ls d. 2612 times Lsarrow_forward15: A star has a parallax angle of 0.0270 arcseconds and an apparent magnitude of 4.641. What is the distance to this star? Answer: 37 16: What is the absolute magnitude of this star? Answer:1.8 17: Is this star more or less luminous than the Sun? Answer "M" for More luminous or "L" for Less luminous. (HINT: the absolute magnitude of the Sun is 4.8) Answer: M 18: What is the luminosity of this star? (HINT: The luminosity of the Sun is 3.85×1026 W.) Please answer question #18, #15-17 are correct, the photos provide the work for them.arrow_forwardThe Hα spectral line has a rest wavelength of 6562.8 ˚A (remember: 1 ˚A = 10−10 m). In star A, the lineis seen at 6568.4 ˚A, in star B it’s seen at 6560.3 ˚A, and in star C it’s seen at 6562.8 ˚A. Which star ismoving the fastest (along the line of sight) and what is the radial velocity of each star?arrow_forward
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