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 22, Problem 47Q
To determine
(a)
The distance to the globular cluster from earth named as RR Lyrae star in astronomical units.
To determine
(b)
The distance to the globular cluster from earth named as RR Lyrae star in parsecs.
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a) Calculate the period of the solar system's orbit around the Milky Way. Assume that we are 8.5
kpc from the galactic center and assume that the mass of the Milky Way interior to our orbit is
~ 10¹¹ solar masses.
Alpha Centauri is a multiple star system only 1.34 parsecs away. The apparent magnitudes of the
two main stars are:
a Cen A: my = +0.01;
a Cen B: my = +1.33.
b) Calculate the ratio of the flux we receive in the V filter from a Cen A to the flux we receive
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c) Calculate the absolute magnitude My of a Cen B.
An O8 V star has an apparent visual magnitude of +5. Use the method of spectroscopic parallax to estimate the distance to the star (in pc). (Hints: Refer to one of the H–R diagrams in the chapter, and use the magnitude–distance formula,
d = 10(mV − MV + 5)/5
where d is the distance in parsecs, mV and MV are the apparent and absolute visual magnitude respectively.)
An astronomical image shows two objects that have the same apparent magnitude, i.e., the same brightness. However, spectroscopic follow up observations indicate that while one is a star that is within our galaxy, at a distance dgal away, and has the same luminosity as the Sun, the other is a quasar and has 100x the luminosity of the entire Milky Way galaxy. What is the distance to the quasar? (You may assume, for this rough calculation, that the Milky Way has 1011 stars and that they all have the luminosity as the Sun.) Give your response in Mpc. Value: dgal = 49 pc
Chapter 22 Solutions
Universe: Stars And Galaxies
Ch. 22 - Prob. 1QCh. 22 - Prob. 2QCh. 22 - Prob. 3QCh. 22 - Prob. 4QCh. 22 - Prob. 5QCh. 22 - Prob. 6QCh. 22 - Prob. 7QCh. 22 - Prob. 8QCh. 22 - Prob. 9QCh. 22 - Prob. 10Q
Ch. 22 - Prob. 11QCh. 22 - Prob. 12QCh. 22 - Prob. 13QCh. 22 - Prob. 14QCh. 22 - Prob. 15QCh. 22 - Prob. 16QCh. 22 - Prob. 17QCh. 22 - Prob. 18QCh. 22 - Prob. 19QCh. 22 - Prob. 20QCh. 22 - Prob. 21QCh. 22 - Prob. 22QCh. 22 - Prob. 23QCh. 22 - Prob. 24QCh. 22 - Prob. 25QCh. 22 - Prob. 26QCh. 22 - Prob. 27QCh. 22 - Prob. 28QCh. 22 - Prob. 29QCh. 22 - Prob. 30QCh. 22 - Prob. 31QCh. 22 - Prob. 32QCh. 22 - Prob. 33QCh. 22 - Prob. 34QCh. 22 - Prob. 35QCh. 22 - Prob. 36QCh. 22 - Prob. 37QCh. 22 - Prob. 38QCh. 22 - Prob. 39QCh. 22 - Prob. 40QCh. 22 - Prob. 41QCh. 22 - Prob. 42QCh. 22 - Prob. 43QCh. 22 - Prob. 44QCh. 22 - Prob. 45QCh. 22 - Prob. 46QCh. 22 - Prob. 47QCh. 22 - Prob. 48QCh. 22 - Prob. 49QCh. 22 - Prob. 50Q
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