Horizons: Exploring the Universe (MindTap Course List)
14th Edition
ISBN: 9781305960961
Author: Michael A. Seeds, Dana Backman
Publisher: Cengage Learning
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Chapter 20, Problem 6P
To determine
The size of the smallest Gausses signal element that could be seen from mars closest approach to earth.
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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?
The Mars Reconnaissance Orbiter
(MRO) flies at an average altitude of 280km above the Martian Surface.
If its cameras have an angular resolution of 0.2 arc seconds, what is the
size of the smallest objects that the
MRO
can detect on the Martian surface?
Use the
equation:
S =x × d / 206265 arcseconds / radian
, where S is the true size of the object, d is the distance from the detector to the object, and x is the angular size of the object. Your answer will be in km (you can
ignore the radians unit (it should appear, but the equation made a simplifying assumption that dropped it out.
Think of our Milky Way Galaxy as a flat circular 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 in light years would the nearest such civilization be from us on average? Show your working. (Hint: Begin by calculating the area of the disk. Find the area of one of a 1,000 squares. Consider the separation of the centres of two adjacent squares.)
Chapter 20 Solutions
Horizons: Exploring the Universe (MindTap Course List)
Ch. 20 - If life is based on information, what is that...Ch. 20 - How does the DNA molecule produce a copy of...Ch. 20 - What would happen to a life-form if the genetic...Ch. 20 - What would happen to a life-form if the...Ch. 20 - Give an example of natural selection acting on new...Ch. 20 - Prob. 6RQCh. 20 - Why do scientists generality think that liquid...Ch. 20 - Prob. 8RQCh. 20 - What is the significance of the Miller-Urey...Ch. 20 - Prob. 10RQ
Ch. 20 - Prob. 11RQCh. 20 - Why is it reasonable to suspect that travel...Ch. 20 - How does the stability of technological...Ch. 20 - Prob. 14RQCh. 20 - Prob. 15RQCh. 20 - Prob. 16RQCh. 20 - How Do We know? Why are scientists confident that...Ch. 20 - Do you expect that hypothetical alien recipients...Ch. 20 - Prob. 2DQCh. 20 - Prob. 3DQCh. 20 - A single human cell encloses about 1.5 m of DNA,...Ch. 20 - If you represent Earth’s history by a line 1 m...Ch. 20 - Prob. 3PCh. 20 - If a star must remain on the main sequence for at...Ch. 20 - Prob. 5PCh. 20 - Prob. 6PCh. 20 - Prob. 7PCh. 20 - Calculate the numb of communicative civilizations...Ch. 20 - The star cluster shown in the image in Figure UN...Ch. 20 - Prob. 2LTL
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