Life in the Universe (4th Edition)
4th Edition
ISBN: 9780134089089
Author: Jeffrey O. Bennett, Seth Shostak
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 12, Problem 8RQ
Why do SETI researchers assume that beacon signals would be designed for easy decoding, and how might we recognize them?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
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?
A radio broadcast left Earth in 1911. How far in light years has it traveled?
If there is, on average, 1 star system per 400 cubic light years, how many star systems has this broadcast reached?
Assume that the fraction of these star systems that have planets is 0.50 and that, in a given planetary system, the average number of planets that have orbited in the habitable zone for 4 billion years is 0.20. How many possible planets with life could have heard this signal?
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.
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...
Additional Science Textbook Solutions
Find more solutions based on key concepts
Choose the best answer to each of the following. Explain your reasoning. Which of the following did not occur d...
Cosmic Perspective Fundamentals
The force, when you push against a wall with your fingers, they bend.
Conceptual Physics (12th Edition)
31. (I) A novice skier starting from rest, slides down an icy frictionless 8.0° incline whose vertical height i...
Physics: Principles with Applications
Whether the refractive index of the oil is greater than the refractive index of water or not.
Physics (5th Edition)
9. The forces in FIGURE EX6.9 act on a 2.0 kg object. What are the values of ax and ay, the x- and y-componen...
Physics for Scientists and Engineers: A Strategic Approach, Vol. 1 (Chs 1-21) (4th Edition)
Knowledge Booster
Learn more about
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
- What are the advantages to using radio waves for communication between civilizations that live around different stars? List as many as you can.arrow_forwardWhat is the difference between chemical evolution and biological evolution?arrow_forwardWhat are the three requirements that scientists believe an environment needs to supply life with in order to be considered habitable?arrow_forward
- The Drake equation attempts to calculate the number of communicative civilizations in the galaxy. What does the factor F S represent and why is it considered to be the most uncertain of all the factors in this equation?arrow_forwardTutorial A radio broadcast left Earth in 1923. How far in light years has it traveled? If there is, on average, 1 star system per 400 cubic light years, how many star systems has this broadcast reached? Assume that the fraction of these star systems that have planets is 0.50 and that, in a given planetary system, the average number of planets that have orbited in the habitable zone for 4 billion years is 0.40. How many possible planets with life could have heard this signal? Part 1 of 3 To figure out how many light years a signal has traveled we need to know how long since the signal left Earth. If the signal left in 1923, distance in light years = time since broadcast left Earth. d = tnow - broadcast d = 97 97 light years Part 2 of 3 Since the radio signal travels in all directions, it expanded as a sphere with a radius equal to the distance it has traveled so far. To determine the number of star systems this signal has reached, we need to determine the volume of that sphere. V, = Vb…arrow_forwardTutorial A radio broadcast left Earth in 1925. How far in light years has it traveled? If there is, on average, 1 star system per 400 cubic light years, how many star systems has this broadcast reached? Assume that the fraction of these star systems that have planets is 0.30 and that, in a given planetary system, the average number of planets that have orbited in the habitable zone for 4 billion years is 0.85. How many possible planets with life could have heard this signal? Part 1 of 3 To figure out how many light years a signal has traveled we need to know how long since the signal left Earth. If the signal left in 1925, distance in light years = time since broadcast left Earth. d = tnow - tbroadcast d = light years Submit Skip (you cannot come back)arrow_forward
- If you detected radio signals with an average wavelength of 37 cm and suspected that they came from a civilization on a distant Earth-like exoplanet, roughly how much of a change in wavelength (in cm) should you expect to detect as a result of the orbital motion of the distant exoplanet? (Hint: Use the Doppler shift formula.) (Note: Earth's orbital velocity is 30 km/s.) cmarrow_forwardIf you detected radio signals with an average wavelength of 68 cm and suspected that they came from a civilization on a distant Earth-like exoplanet, roughly how much of a change in wavelength (in cm) should you expect to detect as a result of the orbital motion of the distant exoplanet? (Hint: Use the Doppler shift formula.) (Note: Earth's orbital velocity is 30 km/s.)arrow_forwardConsider Figure 25-8. What is the ratio of the length of time since the origin of fish to the time since the origin of mammals? What does this value indicate?arrow_forward
- Suppose there are l0,000 civilizations broadcasting radio signals in the Milky Way GaIaxy right now. On average, how many stars would we have to search before we would expect to hear a signal? Assume there are 500 billion stars in the galaxy. How would the answer change if there were only 100 civilizations instead of 10,000?arrow_forwardWhen Mars is 90 million km 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?arrow_forward
arrow_back_ios
arrow_forward_ios
Recommended textbooks for you
Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Stars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage Learning
AstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax
Stars and GalaxiesPhysicsISBN:9781305120785Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Foundations of Astronomy (MindTap Course List)
Physics
ISBN:9781337399920
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
Stars and Galaxies (MindTap Course List)
Physics
ISBN:9781337399944
Author:Michael A. Seeds
Publisher:Cengage Learning
Astronomy
Physics
ISBN:9781938168284
Author:Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher:OpenStax
Stars and Galaxies
Physics
ISBN:9781305120785
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
General Relativity: The Curvature of Spacetime; Author: Professor Dave Explains;https://www.youtube.com/watch?v=R7V3koyL7Mc;License: Standard YouTube License, CC-BY