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 21, Problem 38Q
To determine
(a)
Theradius of the orbit.
To determine
(b)
Theproof that the mass of the x-ray source is at least
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Chapter 21 Solutions
Universe: Stars And Galaxies
Ch. 21 - Prob. 1QCh. 21 - Prob. 2QCh. 21 - Prob. 3QCh. 21 - Prob. 4QCh. 21 - Prob. 5QCh. 21 - Prob. 6QCh. 21 - Prob. 7QCh. 21 - Prob. 8QCh. 21 - Prob. 9QCh. 21 - Prob. 10Q
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- 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 pcarrow_forwardThe total intensity of light measured on earth, from an ecliptic binary, is plotted in the figure as a function of time (it's called a light curve). Careful measurements indicate that the intensities of the incident light from the stars corresponding to the minima are respectively 90 and 63 percent of the maximum intensity, Io. temperatures of two stars in an eclipsing binary are T1 and T2 (T1 > T2), and the corresponding radii (R1 > R2), respectively. received from both stars.Surface аге R1 and R2 Find the ratio T1/T2. Round you answer to two significant figures. 1.0- 0.8 1/1o =0.90 0.6- 04- 1|1. =0.63 0.2 1.0 2.0 3.0 4.0 5.0 6.0 Time (days)arrow_forwardWR 68a is a relatively newly discovered (2015) double-lined spectroscopic binary. It has an orbital pe- riod of 5.22 days, a nearly circular orbit, and photometric light curves that are fit best using an inclination, i≈ 80°. Spectral lines show maximum Doppler shifts in the two components of K₁ = 144 km/s and Kg = 295 km/s. Find the masses of the two components. Your answers should be given in units of Mearrow_forward
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