Life in the Universe (4th Edition)
4th Edition
ISBN: 9780134089089
Author: Jeffrey O. Bennett, Seth Shostak
Publisher: PEARSON
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Chapter 12, Problem 49IF
Power Used by E.T. A modern SETI search using the 300-meter-diameter Arecibo Radio Telescope in Puerto Rico could pick up a 10-million-watt signal from 1000 light-years away (assuming that the broadcasting aliens had a transmitting antenna that was also 300 meters in diameter). Suppose we used Arecibo to search the far side of the Milky Way Galaxy (roughly 80,000 light-years away). Making the same assumptions about our setup and the transmitting antenna, determine how powerful the alien transmitter would have to be for us to detect the signal.
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In a globular cluster, astronomers (someday) discover a star with the same mass as our Sun, but consisting entirely of hydrogen and helium. Is this star a good place to point our SETI antennas and search for radio signals from an advanced civilization?
Group of answer choices
No, because such a star (and any planets around it) would not have the heavier elements (carbon, nitrogen, oxygen, etc.) that we believe are necessary to start life as we know it.
Yes, because globular clusters are among the closest star clusters to us, so that they would be easy to search for radio signals.
Yes, because we have already found radio signals from another civilization living near a star in a globular cluster.
No, because such a star would most likely not have a stable (main-sequence) stage that is long enough for a technological civilization to develop.
Yes, because such a star is probably old and a technological civilization will have had a long time to evolve and develop there.
When Mars is 90 million km (9 x 10^10 m) from Earth, a) How long would it take for a radio wave from a video camera mounted on the back of a Mars Rover to tell ground control on earth that the Rover is about to go over a cliff? b) How long would it take for a radio signal from Earth to reach the Rover saying "STOP". c) Why do our Mars Rovers have to be "intelligent" enough to figure out how to deal with obstacles themselves?
Suppose that stars were born at random times over the last 1010 years. The rate of star formation is simply the number of stars divided by 1010 years. The fraction of stars with detected extrasolar planets is at least 11 %. The rate of star formation can be multiplied by this fraction to find the rate planet formation. How often (in years) does a planetary system form in our galaxy? Assume the Milky Way contains 3 × 1011 stars.
Chapter 12 Solutions
Life in the Universe (4th Edition)
Ch. 12 - What is the purpose of the Drake equation? Define...Ch. 12 - What is convergent evolution? How does this idea...Ch. 12 - Prob. 3RQCh. 12 - Prob. 4RQCh. 12 - Briefly describe early attempts at interplanetary...Ch. 12 - Briefly discuss early SETI efforts. What do we...Ch. 12 - What are the three general categories of signals...Ch. 12 - Why do SETI researchers assume that beacon signals...Ch. 12 - Summarize the current techniques of radio SETI and...Ch. 12 - Explain why it is reasonable to imagine optical or...
Ch. 12 - Prob. 11RQCh. 12 - What are the three distinct categories of...Ch. 12 - Briefly discuss some of the issues that would...Ch. 12 - Discuss several types of claims about alien...Ch. 12 - Humans are the crown of creation and an inevitable...Ch. 12 - If, for some reason, we humans were to suddenly...Ch. 12 - Prob. 17TYUCh. 12 - Most of the intelligence in the universe is not...Ch. 12 - Because SETI researchers are listening to star...Ch. 12 - Prob. 20TYUCh. 12 - Prob. 21TYUCh. 12 - Looking for signals from star systems is a poor...Ch. 12 - If 10,000 people saw the same UFO, scientists...Ch. 12 - The absence of any scientific evidence for alien...Ch. 12 - The end result of a calculation with the Drake...Ch. 12 - Which of the following statements is true about...Ch. 12 - The fact that marine predators like dolphins and...Ch. 12 - Which of the following would lead an animal to a...Ch. 12 - Prob. 29TYUCh. 12 - Why are we more likely to be able to detect a...Ch. 12 - What is the distinguishing characteristic that...Ch. 12 - Two-way conversation with other societies is...Ch. 12 - Prob. 33TYUCh. 12 - One reason scientists doubt that crop circles have...Ch. 12 - Alien Visits. Learn more about a particular claim...Ch. 12 - Prob. 39IFCh. 12 - Evolution of Intelligence. Based on your...Ch. 12 - Intelligence on Other Worlds. Consider again the...Ch. 12 - Talking Back. Suppose SETI were to find a signal...Ch. 12 - Contact. Watch the movie Contact, paying careful...Ch. 12 - Invasions of Movie Aliens. Choose a science...Ch. 12 - Prob. 47IFCh. 12 - Actual SETI Searches. Project Phoenix, the largest...Ch. 12 - Power Used by E.T. A modern SETI search using the...Ch. 12 - Detecting Signals. SETI scientists are sometimes...Ch. 12 - Societal Reaction. It is frequently said that the...Ch. 12 - Dealing with UFO Claims. Given the large number of...
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