21st Century Astronomy
6th Edition
ISBN: 9780393428063
Author: Kay
Publisher: NORTON
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Chapter 16, Problem 20QP
To determine
The distances to the galaxies.
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Skeleton Densities.
Part A: Create a ratio the neutron star density (ρns = 1015 g/cm3) to the white dwarf density (ρwd = 2×106 g/cm3).
Please round your answer to one significant digit.
Part B: Which stellar property results in electron degeneracy pressure supporting white dwarfs and neutron degeneracy pressure supporting neutron stars?
The figure below shows the spectra of two galaxies A and B.
Please can i get help with this questions below:
1. Which of these galaxies has ongoing star formation? How can you tell?2. One of these galaxies has Hubble type E3 while the other is SBb. Which is which? What does the 3 inE3 tell you about the galaxy? What does the SB in SBb tell you about the galaxy?3. What effects would dust have on the two spectra?4. Which galaxy would you expect to have more far-infrared emission? Expl
1.2
1.0
0.8
0.6
Cosmic background
data from COBE
0.4
0.2
0.0
0.5
10
Wavelength A in mm
c)
Background (CMB) undertaken by the COBE satellite. Use this diagram to estimate the
current temperature of the CMB. Based on your estimate, what would the temperature of
the CMB have been at a redshift of z = 5000?
The left hand diagram above shows the results from observations of the Cosmic Microwave
Radiated Intensity per Unit Wavelength
(16° Watts/m per mm)
Chapter 16 Solutions
21st Century Astronomy
Ch. 16.1 - Prob. 16.1CYUCh. 16.3 - Prob. 16.3CYUCh. 16.4 - Prob. 16.4CYUCh. 16.5 - Prob. 16.5CYUCh. 16 - Prob. 1QPCh. 16 - Prob. 2QPCh. 16 - Prob. 3QPCh. 16 - Prob. 4QPCh. 16 - Prob. 5QPCh. 16 - Prob. 6QP
Ch. 16 - Prob. 8QPCh. 16 - Prob. 9QPCh. 16 - Prob. 10QPCh. 16 - Prob. 11QPCh. 16 - Prob. 12QPCh. 16 - Prob. 13QPCh. 16 - Prob. 14QPCh. 16 - Prob. 15QPCh. 16 - Prob. 16QPCh. 16 - Prob. 17QPCh. 16 - Prob. 18QPCh. 16 - Prob. 19QPCh. 16 - Prob. 20QPCh. 16 - Prob. 21QPCh. 16 - Prob. 23QPCh. 16 - Prob. 24QPCh. 16 - Prob. 25QPCh. 16 - Prob. 26QPCh. 16 - Prob. 27QPCh. 16 - Prob. 28QPCh. 16 - Prob. 29QPCh. 16 - Prob. 30QPCh. 16 - Prob. 31QPCh. 16 - Prob. 32QPCh. 16 - Prob. 33QPCh. 16 - Prob. 34QPCh. 16 - Prob. 35QPCh. 16 - Prob. 36QPCh. 16 - Prob. 37QPCh. 16 - Prob. 38QPCh. 16 - Prob. 39QPCh. 16 - Prob. 40QPCh. 16 - Prob. 41QPCh. 16 - Prob. 42QPCh. 16 - Prob. 43QPCh. 16 - Prob. 44QPCh. 16 - Prob. 45QP
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