21st Century Astronomy
6th Edition
ISBN: 9780393428063
Author: Kay
Publisher: NORTON
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 15, Problem 42QP
(a)
To determine
Time taken for the total collapse.
(b)
To determine
Time spent by Sun on Hayashi track.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
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?
1. A star on the main sequence has a surface temperature of10,000 K. Use the H-R diagram to determine it’s luminosity(approximately) and then calculate it’s mass and age (you mayuse solar units). If it were a red giant, could we do this?
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?
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
- What is the first event that happens to a star with roughly the mass of our Sun that exhausts the hydrogen in its core and stops the generation of energy by the nuclear fusion of hydrogen to helium? Describe the sequence of events that the star undergoes.arrow_forwardDescribe what happens when a star forms. Begin with a dense core of material in a molecular cloud and trace the evolution up to the time the newly formed star reaches the main sequence.arrow_forwardFrom the information in Figure 15.21, estimate the speed with which the particles in the CME in parts (c) and (d) are moving away from the Sun. Figure 15.21 Flare and Coronal Mass Ejection. This sequence of four images shows the evolution over time of a giant eruption on the Sun. (a) The event began at the location of a sunspot group, and (b) a flare is seen in far-ultraviolet light. (c) Fourteen hours later, a CME is seen blasting out into space. (d) Three hours later, this CME has expanded to form a giant cloud of particles escaping from the Sun and is beginning the journey out into the solar system. The white circle in (c) and (d) shows the diameter of the solar photosphere. The larger dark area shows where light from the Sun has been blocked out by a specially designed instrument to make it possible to see the faint emission from the corona. (credit a, b, c, d: modification of work by SOHO/EIT, SOHO/LASCO, SOHO/MDI (ESA & NASA))arrow_forward
- (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_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_forwardThis star has a mass of 3.3 MSun. What is the main sequence lifetime of this star? You may assume that the lifetime of the sun is 1010 yr. Hint: The simple relation is that lifetime is proportional to mass divided by luminosity. If you use these quantities in solar masses and solar luminosities, then this relation tells you how many times longer than the Sun the star will live.arrow_forward
- A 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_forwardThe Sun is estimated to have about 5.00 billion years left in it’s “normal” (main sequence) lifetime. Assume the average “burn” rate that you computed in question #1, what % of the Sun’s current mass will have been converted at the end of it’s estimated 5.00 billion years of additional life?arrow_forwardTHIS WAS ALREADY ASKED; just need the question labeled 1.***** If the nuclear fusion reaction of converting 4 H → He occurs at an efficiency of 0.7%, and that mass is converted into energy according to the equation E = mc2, then estimate the Main Sequence lifetime of the Sun (spectral type G2) in years if the luminosity of the Sun is 3.83 × 1033 ergs s−1. Assume the Sun’s core (10% of the total mass) is converted from H into He. The Sun’s mass is M⊙ = 1.9891 × 1033 g. Make the same assumptions as the previous problem; however, now estimate the lifetime of star whose spectral type is B0 if the total mass of the star is M = 17.5M⊙, and it has a total luminosity L = 5.2×104L⊙. How does the Main Sequence lifetime of the B0 type star compare to the Main Sequence lifetime you calculated for of the Sun?arrow_forward
- Why was the detection of solar neutrinos important? a) They have been suggested as an important source of solar energy. b) They provide direct evidence for solar oscillations. c) The provide direct evidence for the proton-proton chain. Where does nuclear energy production (fusion) occur in the Sun? a) In the nuclear zone b) In all layers of the Sun c) In the photosphere d) In the corearrow_forwardWhy does the Sun not collapse under its enormous weight? a) The Sun is about 4.6 billion years old. If it could have collapsed by now , it would have. b) Because the Sun is in hydrostatic equilibrium. c) Because the Sun is not in hydrostatic equilibrium. d)More than one of the above.arrow_forwardAs a star runs out of hydrogen to fuel nuclear fusion in its core, changes within the star usually cause it to leave the main sequence, expanding and cooling as it does so. Would a star with a radius 6 times that of the Sun, but a surface temperature 0.4 times that of the Sun, be more, or less luminous than the Sun? Show and explain your reasoning. You may assume the surface area of a sphere is A = 4πr2.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
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
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