Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
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Chapter 21, Problem 22E
When astronomers found the first giant planets with orbits of only a few days, they did not know whether those planets were gaseous and liquid like Jupiter or rocky like Mercury. The observations of HD 209458 settled this question because observations of the transit of the star by this planet made it possible to determine the radius of the planet. Use the data given in the text to estimate the density of this planet, and then use that information to explain why it must be a gas giant.
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Chapter 21 Solutions
Astronomy
Ch. 21 - Give several reasons the Orion molecular cloud is...Ch. 21 - Why is star formation more likely to occur in cold...Ch. 21 - Why have we learned a lot about star formation...Ch. 21 - Describe what happens when a star forms. Begin...Ch. 21 - Describe how the T Tauri star stage in the life of...Ch. 21 - Look at the four stages shown in Figure 21.8. In...Ch. 21 - The evolutionary track for a star of 1 solar mass...Ch. 21 - Two protostars, one 10 times the mass of the Sun...Ch. 21 - Compare the scale (size) of a typical dusty disk...Ch. 21 - Why is it so hard to see planets around other...
Ch. 21 - Why did it take astronomers until 1995 to discover...Ch. 21 - Which types of planets are most easily detected by...Ch. 21 - List three ways in which the exoplanets we have...Ch. 21 - List any similarities between discovered...Ch. 21 - What revisions to the theory of planet formation...Ch. 21 - Why are young Jupiters easier to see with direct...Ch. 21 - A friend of yours who did not do well in her...Ch. 21 - Observations suggest that it takes more than 3...Ch. 21 - Suppose you wanted to observe a planet around...Ch. 21 - Why were giant planets close to their stars the...Ch. 21 - Exoplanets in eccentric orbits experience large...Ch. 21 - When astronomers found the first giant planets...Ch. 21 - An exoplanetary system has two known planets....Ch. 21 - Kepler’s third law says that the orbital period...Ch. 21 - Calculate the transit depth for an M dwarf star...Ch. 21 - If a transit depth of 0.00001 can be detected with...Ch. 21 - What fraction of gas giant planets seems to have...
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