Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
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Textbook Question
Chapter 19, Problem 17E
Which of the following can you determine about a star without knowing its distance, and which can you not determine: radial velocity, temperature, apparent brightness, or luminosity? Explain.
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Chapter 19 Solutions
Astronomy
Ch. 19 - Explain how parallax measurements can be used to...Ch. 19 - Suppose you have discovered a new cepheid variable...Ch. 19 - Explain how you would use the spectrum of a star...Ch. 19 - Which method would you use to obtain the distance...Ch. 19 - What are the luminosity class and spectral type of...Ch. 19 - The meter was redefined as a reference to Earth,...Ch. 19 - While a meter is the fundamental unit of length,...Ch. 19 - Most distances in the Galaxy are measured in...Ch. 19 - The AU is defined as the average distance between...Ch. 19 - What would be the advantage of making parallax...
Ch. 19 - Parallaxes are measured in fractions of an...Ch. 19 - For centuries, astronomers wondered whether comets...Ch. 19 - The Sun is much closer to Earth than are the...Ch. 19 - Parallaxes of stars are sometimes measured...Ch. 19 - Estimating the luminosity class of an M star is...Ch. 19 - Figure 19.9 is the light curve for the prototype...Ch. 19 - Which of the following can you determine about a...Ch. 19 - A G2 star has a luminosity 100 times that of the...Ch. 19 - A star has a temperature of 10,000 K and a...Ch. 19 - What is the advantage of measuring a parallax...Ch. 19 - What is the disadvantage of the parallax method,...Ch. 19 - Luhman 16 and WISE 0720 are brown dwarfs, also...Ch. 19 - Most stars close to the Sun are red dwarfs. What...Ch. 19 - Why would it be easier to measure the...Ch. 19 - When Henrietta Leavitt discovered the...Ch. 19 - A radar astronomer who is new at the job claims...Ch. 19 - The New Horizons probe flew past Pluto in July...Ch. 19 - Estimate the maximum and minimum time it takes a...Ch. 19 - The Apollo program (not the lunar missions with...Ch. 19 - In 1974, the Arecibo Radio telescope in Puerto...Ch. 19 - Demonstrate that 1 pc equals 3.091013 k m and that...Ch. 19 - The best parallaxes obtained with Hipparcos have...Ch. 19 - Astronomers are always making comparisons between...Ch. 19 - Gaia will have greatly improved precision over the...Ch. 19 - Using the same techniques as used in Exercise...Ch. 19 - The human eye is capable of an angular resolution...Ch. 19 - How much better is the resolution of the Gaia...Ch. 19 - The most recently discovered system close to Earth...Ch. 19 - What would the parallax of Luhman 16 (see Exercise...Ch. 19 - The New Horizons probe that passed by Pluto during...Ch. 19 - What physical properties are different for an M...
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