Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
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Textbook Question
Chapter 6, Problem 12E
Look back at Figure 6.18 of Cygnus A and read its caption again. The material in the giant lobes at the edges of the image had to have been ejected from the center at least how many years ago?
Figure 6.18 Radio Image. This image has been constructed of radio observations at the Very Large Array of a galaxy called Cygnus A. Colors have been added to help the eye sort out regions of different radio intensities. Red regions are the most intense, blue the least. The visible galaxy would be a small dot in the center of the image. The radio image reveals jets of expelled material (more than 160,000 light-years long) on either side of the galaxy. (credit: NRAO/AUI)
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Chapter 6 Solutions
Astronomy
Ch. 6 - What are the three basic components of a modern...Ch. 6 - Name the two spectral windows through which...Ch. 6 - List the largest-aperture single telescope...Ch. 6 - When astronomers discuss the apertures of their...Ch. 6 - The Hooker telescope at Palomar Observatory has a...Ch. 6 - What is meant by “reflecting” and “refracting”...Ch. 6 - Why are the largest visible-light telescopes in...Ch. 6 - Compare the eye, photographic film, and CCDs as...Ch. 6 - What is a charge-coupled device (CCD), and how is...Ch. 6 - Why is it difficult to observe at infrared...
Ch. 6 - Radio and radar observations are often made with...Ch. 6 - Look back at Figure 6.18 of Cygnus A and read its...Ch. 6 - Why do astronomers place telescopes in Earth’s...Ch. 6 - What was the problem with the Hubble Space...Ch. 6 - Describe the techniques radio astronomers use to...Ch. 6 - What kind of visible-light and infrared telescopes...Ch. 6 - Describe one visible-light or infrared telescope...Ch. 6 - What happens to the image produced by a lens if...Ch. 6 - What would be the properties of an ideal...Ch. 6 - Many decades ago, the astronomers on the staff of...Ch. 6 - The largest observatory complex in the world is on...Ch. 6 - Suppose you are looking for sites for a...Ch. 6 - Radio astronomy involves wavelengths much longer...Ch. 6 - The dean of a university located near the ocean...Ch. 6 - What is the area, in square meters, of a 10-m...Ch. 6 - Approximately 9000 stars are visible to the naked...Ch. 6 - Theoretically (that is, if seeing were not an...Ch. 6 - In broad daylight, the size of your pupil is...Ch. 6 - How much more light can be gathered by a telescope...Ch. 6 - How much more light can the Keck telescope (with...Ch. 6 - People are often bothered when they discover that...Ch. 6 - Telescopes can now be operated remotely from a...Ch. 6 - The HST cost about $1.7 billion for construction...Ch. 6 - How much more light can the James Webb Space...Ch. 6 - The Palomar telescope’s 5-m mirror weighs 14.5...
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