The Cosmic Perspective (9th Edition)
9th Edition
ISBN: 9780134874364
Author: Jeffrey O. Bennett, Megan O. Donahue, Nicholas Schneider, Mark Voit
Publisher: PEARSON
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Question
Chapter 21, Problem 47EAP
To determine
The expected average number of galaxies similar in size to the milky way in cubes of side-length of 10 million light years.
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Chapter 21 Solutions
The Cosmic Perspective (9th Edition)
Ch. 21 - Prob. 1VSCCh. 21 - Prob. 2VSCCh. 21 - Prob. 3VSCCh. 21 - Prob. 4VSCCh. 21 - Prob. 1EAPCh. 21 - Prob. 2EAPCh. 21 - Prob. 3EAPCh. 21 - Prob. 4EAPCh. 21 - Prob. 5EAPCh. 21 - Prob. 6EAP
Ch. 21 - Prob. 7EAPCh. 21 - Prob. 9EAPCh. 21 - Prob. 10EAPCh. 21 - Prob. 11EAPCh. 21 - Prob. 12EAPCh. 21 - Prob. 13EAPCh. 21 - Prob. 14EAPCh. 21 - Prob. 15EAPCh. 21 - Prob. 16EAPCh. 21 - Prob. 17EAPCh. 21 - Prob. 18EAPCh. 21 - Prob. 19EAPCh. 21 - Prob. 20EAPCh. 21 - Prob. 21EAPCh. 21 - Prob. 22EAPCh. 21 - Prob. 23EAPCh. 21 - Prob. 24EAPCh. 21 - Prob. 25EAPCh. 21 - Prob. 26EAPCh. 21 - Prob. 27EAPCh. 21 - Prob. 28EAPCh. 21 - Prob. 29EAPCh. 21 - Prob. 30EAPCh. 21 - Prob. 31EAPCh. 21 - Prob. 32EAPCh. 21 - Prob. 34EAPCh. 21 - Prob. 36EAPCh. 21 - Life Story of a Spiral. Imagine that you are a...Ch. 21 - Prob. 39EAPCh. 21 - Prob. 40EAPCh. 21 - Prob. 41EAPCh. 21 - Prob. 42EAPCh. 21 - Prob. 43EAPCh. 21 - Prob. 44EAPCh. 21 - Prob. 45EAPCh. 21 - Prob. 46EAPCh. 21 - Prob. 47EAPCh. 21 - A Nearby Starburst. The galaxy M82, shown in...Ch. 21 - Prob. 49EAPCh. 21 - Prob. 50EAPCh. 21 - Prob. 51EAPCh. 21 - Prob. 52EAPCh. 21 - Prob. 53EAP
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.Similar questions
- In which type of model universe is space-time infinite in extent and positively curved? List all possibilities.arrow_forwardWhat does it mean to say that the universe is expanding? What is expanding? For example, is your astronomy classroom expanding? Is the solar system? Why or why not?arrow_forwardSuppose astronomers discover a radio message from a civilization whose planet orbits a star 35 lightyears away. Their message encourages us to send a radio answer, which we decide to do. Suppose our governing bodies take 2 years to decide whether and how to answer. When our answer arrives there, their governing bodies also take two of our years to frame an answer to us. How long after we get their first message can we hope to get their reply to ours? (A question for further thinking: Once communication gets going, should we continue to wait for a reply before we send the next message?)arrow_forward
- In which type of model universe is space-time infinite in extent and open? List all possibilities.arrow_forwardThinking about the ideas of space and time in Einstein’s general theory of relativity, how do we explain the fact that all galaxies outside our Local Group show a redshift?arrow_forwardThere is still some uncertainty in the Hubble constant. (a) Current estimates range from about 19.9 km/s per million light-years to 23 km/s per million light-years. Assume that the Hubble constant has been constant since the Big Bang. What is the possible range in the ages of the universe? Use the equation in the text, T0=1H , and make sure you use consistent units. (b) Twenty years ago, estimates for the Hubble constant ranged from 50 to 100 km/s per Mps. What are the possible ages for the universe from those values? Can you rule out some of these possibilities on the basis of other evidence?arrow_forward
- Construct a timeline for the universe and indicate when various significant events occurred, from the beginning of the expansion to the formation of the Sun to the appearance of humans on Earth.arrow_forwardThink of our Milky Way Galaxy as a flat disk of diameter 100,000 light-years. Suppose we are one of 1000 civilizations, randomly distributed through the disk, interested in communicating via radio waves. How far away would the nearest such civilization be from us (on average)?arrow_forwardWould a human have been possible during the first generation of stars that formed right after the Big Bang? Why or why not?arrow_forward
- Suppose the universe expands forever. Describe what will become of the radiation from the primeval fireball. What will the future evolution of galaxies be like? Could life as we know it survive forever in such a universe? Why?arrow_forwardWhat are some answers to the Fermi paradox? Can you think of some that are not discussed in this chapter?arrow_forward
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