21st Century Astronomy
6th Edition
ISBN: 9780393428063
Author: Kay
Publisher: NORTON
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 15, Problem 37QP
(a)
To determine
Reason why a B8 main-sequence star ionize far more interstellar hydrogen.
(b)
To determine
Properties of star determining whether it can ionize large amounts of interstellar hydrogen.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
What are the on the axes of a Hertzsprung-Russell diagram? (b) Name one thing you can tell about a star from its location in an H-R diagram (Other than luminosity & temperature!) c) Where are most stars located in the diagram?
a) Why don’t stars live forever? Which stars live the longest? b) What is the importance of 1.4 solar masses in stellar evolution?
1. Suppose you observe a tight eclipsing binary with orbital period of 3 days, and radial velocity semi-amplitude for both components of 80 kilometers/second.
a. Without doing any calculation, you know that the mass ratio of the binary is 1:1. Explain why?
b. What are the masses and orbital radii of the two stars?
c. Suppose the binary is perfectly aligned so each eclipse the center of one star goes across the other. How often do you see an eclipse?
d. Suppose one eclipse lasts for 3.5 hours. What is the radius of the stars?
Chapter 15 Solutions
21st Century Astronomy
Ch. 15.1 - Prob. 15.1CYUCh. 15.2 - Prob. 15.2CYUCh. 15.3 - Prob. 15.3CYUCh. 15.4 - Prob. 15.4CYUCh. 15 - Prob. 1QPCh. 15 - Prob. 2QPCh. 15 - Prob. 3QPCh. 15 - Prob. 4QPCh. 15 - Prob. 5QPCh. 15 - Prob. 6QP
Ch. 15 - Prob. 7QPCh. 15 - Prob. 8QPCh. 15 - Prob. 9QPCh. 15 - Prob. 10QPCh. 15 - Prob. 11QPCh. 15 - Prob. 12QPCh. 15 - Prob. 13QPCh. 15 - Prob. 14QPCh. 15 - Prob. 15QPCh. 15 - Prob. 16QPCh. 15 - Prob. 17QPCh. 15 - Prob. 18QPCh. 15 - Prob. 19QPCh. 15 - Prob. 20QPCh. 15 - Prob. 21QPCh. 15 - Prob. 22QPCh. 15 - Prob. 23QPCh. 15 - Prob. 24QPCh. 15 - Prob. 25QPCh. 15 - Prob. 26QPCh. 15 - Prob. 27QPCh. 15 - Prob. 28QPCh. 15 - Prob. 29QPCh. 15 - Prob. 30QPCh. 15 - Prob. 31QPCh. 15 - Prob. 32QPCh. 15 - Prob. 33QPCh. 15 - Prob. 35QPCh. 15 - Prob. 36QPCh. 15 - Prob. 37QPCh. 15 - Prob. 38QPCh. 15 - Prob. 39QPCh. 15 - Prob. 40QPCh. 15 - Prob. 41QPCh. 15 - Prob. 42QPCh. 15 - Prob. 43QPCh. 15 - Prob. 44QPCh. 15 - Prob. 45QP
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
- (a) The surface temperature of a star is 25,000 K and it has a luminosity about 1% that of our Sun. What kind of star is it? (B) The surface temperature of a star is 3,000 K and it has a luminosity about 104 time that of our Sun. What kind of star is it?arrow_forwardA group of graduate students, bored during a cloudy night at a the observatory, begin to make bets about the time different stars will take to evolve. If they have a cluster of stars which were all born roughly the same time, and want to know which star will become a red giant first, which of the following stars should they bet on? a. a star that would type O on the main sequence star b. a star about 1/2 the mass of our sun c. a star about 8% the mass of our sun d. all stars reach the red giant stage in roughly the same number of yearsarrow_forwardA star with spectral type A0 has a surface temperature of 9600 K and a radius of 2.2 RSun. How many times more luminous is this star than the Sun? (if it is less luminous enter a number less than one) This star has a mass of 3.3 MSun. Using the simple approximation that we made in class, what is the main sequence lifetime of this star? You may assume that the lifetime of the sun is 1010 yr. Compare this to the lifetime of a A0 star listed in Table 22.1 (computed using a more sophisticated approach). Is the value you calculated in the previous problem longer or shorter than what is reported in the table? (L for longer, S for shorter) (You only get one try at this problem.)arrow_forward
- a Given a star formation rate of 50 M yr−1, what is the measured Hα flux, in erg/sec? b What types of stars are responsible for this flux? c How do they produce the flux? d Why are they an indicator of star formation?arrow_forwardA star such as our Sun will eventually evolve to a “red giant” star and then to a “whitedwarf” star. A typical white dwarf is approximately the size of Earth, and its surfacetemperature is about 2.5×103 K. A typical red giant has a surface temperature of 3.0×104K and a radius ~100,000 times larger than that of a white dwarf.a) What is the average radiated power per unit area by each of these types of stars?b) What is the ratio of total power radiated from the white dwarf over the power of thered giant? assume that both stars have emission e = 1arrow_forward1. A star with an original mass of 9MSun undergoes an active period where it experiences mass loss via a super-wind over 1.1 million years. Its new mass is 3MSun. What was the mass-loss rate each year the super-wind was active? (Enter your answer in MSun/yr.)arrow_forward
- A red giant star has a temperature of 3900 K and a luminosity of 13600 LSun. How many times bigger is this star than the Sun? Hint: You need the surface temperature of the sun for this problem. Use the value in the book, 5800K.arrow_forwardwhat is a star? define neclear fusion? how does nuclear fusion keep the star keep burning ?arrow_forwardWhat are the a) luminosity and b)wavelength of maximum emission for a star with a surface temperature is 2,000K and a size of 1.0*108m?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 LearningStars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage LearningAstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax
- Horizons: Exploring the Universe (MindTap Course ...PhysicsISBN:9781305960961Author: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
Horizons: Exploring the Universe (MindTap Course ...
Physics
ISBN:9781305960961
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning