Universe: Stars And Galaxies
6th Edition
ISBN: 9781319115098
Author: Roger Freedman, Robert Geller, William J. Kaufmann
Publisher: W. H. Freeman
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 17, Problem 10Q
To determine
(a)
The radial velocity of star.
To determine
(b)
The direction of motion of star relative to Earth.
To determine
(c)
The actual wavelength of star.
To determine
(d)
The reason for the answer depends on the distance of star from the Sun.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
A star has a measured radial velocity of 100 km/s. If you measure the wavelength of a particular spectral line of Hydrogen as 486.42 nm, what was the laboratory wavelength (in nm) of the line? (Round your answer to at least one decimal place.)
Which spectral line does this likely correspond to?
Balmer-alpha (656.3 nm)
Balmer-beta (486.1 nm)
Balmer-gamma (434.0 nm)
Balmer-delta (410.2 nm)
A star has a parallax angle of 0.0270 arcseconds and an apparent magnitude of 4.641. The distance to this star is 37.03 parsecs and the absolute magintude is 1.79.
18: What is the luminosity of this star? (HINT: The luminosity of the Sun is 3.85×1026 W.) Using the Forumla M1 - M2 = -2.5 log(L1/L2)
the absolute magnitude of the Sun is 4.8
Imagine that you are an astronomer studying a star 4 parsecs away (a parsec is
3.09x1016
m). You measure the flux coming from this star with your telescope, getting
a value of 2.3x10-12 W m-².
What is the luminosity of this star?
Chapter 17 Solutions
Universe: Stars And Galaxies
Ch. 17 - Prob. 1QCh. 17 - Prob. 2QCh. 17 - Prob. 3QCh. 17 - Prob. 4QCh. 17 - Prob. 5QCh. 17 - Prob. 6QCh. 17 - Prob. 7QCh. 17 - Prob. 8QCh. 17 - Prob. 9QCh. 17 - Prob. 10Q
Ch. 17 - Prob. 11QCh. 17 - Prob. 12QCh. 17 - Prob. 13QCh. 17 - Prob. 14QCh. 17 - Prob. 15QCh. 17 - Prob. 16QCh. 17 - Prob. 17QCh. 17 - Prob. 18QCh. 17 - Prob. 19QCh. 17 - Prob. 20QCh. 17 - Prob. 21QCh. 17 - Prob. 22QCh. 17 - Prob. 23QCh. 17 - Prob. 24QCh. 17 - Prob. 25QCh. 17 - Prob. 26QCh. 17 - Prob. 27QCh. 17 - Prob. 28QCh. 17 - Prob. 29QCh. 17 - Prob. 30QCh. 17 - Prob. 31QCh. 17 - Prob. 32QCh. 17 - Prob. 33QCh. 17 - Prob. 34QCh. 17 - Prob. 35QCh. 17 - Prob. 36QCh. 17 - Prob. 37QCh. 17 - Prob. 38QCh. 17 - Prob. 39QCh. 17 - Prob. 40QCh. 17 - Prob. 41QCh. 17 - Prob. 42QCh. 17 - Prob. 43QCh. 17 - Prob. 44QCh. 17 - Prob. 45QCh. 17 - Prob. 46QCh. 17 - Prob. 47QCh. 17 - Prob. 48QCh. 17 - Prob. 49QCh. 17 - Prob. 50QCh. 17 - Prob. 51QCh. 17 - Prob. 52QCh. 17 - Prob. 53QCh. 17 - Prob. 54QCh. 17 - Prob. 55QCh. 17 - Prob. 56QCh. 17 - Prob. 57QCh. 17 - Prob. 58QCh. 17 - Prob. 59QCh. 17 - Prob. 60QCh. 17 - Prob. 61QCh. 17 - Prob. 62QCh. 17 - Prob. 63QCh. 17 - Prob. 64QCh. 17 - Prob. 65QCh. 17 - Prob. 66QCh. 17 - Prob. 67QCh. 17 - Prob. 68QCh. 17 - Prob. 69QCh. 17 - Prob. 70QCh. 17 - Prob. 71QCh. 17 - Prob. 72QCh. 17 - Prob. 73QCh. 17 - Prob. 74QCh. 17 - Prob. 75QCh. 17 - Prob. 76QCh. 17 - Prob. 77QCh. 17 - Prob. 78QCh. 17 - Prob. 79QCh. 17 - Prob. 80Q
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
- How does one go about these questions?arrow_forwardThe Hα spectral line has a rest wavelength of 6562.8 ˚A (remember: 1 ˚A = 10−10 m). In star A, the lineis seen at 6568.4 ˚A, in star B it’s seen at 6560.3 ˚A, and in star C it’s seen at 6562.8 ˚A. Which star ismoving the fastest (along the line of sight) and what is the radial velocity of each star?arrow_forward"51 Pegasi" is the name of the first normal star (besides the Sun) around which a planet was discovered. It is in the constellation Pegasus the horse. Its parallax is measured to be 0.064 arcsec. a. What is its distance from us? b. The apparent brightness is 1.79 × 10-10 J/(s·m2 ). What is the luminosity? How does that compare with that of the Sun? Look up the temperature: how doarrow_forward
- Physics written by hand.arrow_forwardYou observe a star with a telescope over the course of a year. You find that this star has a flux that is one-trillionth of the Sun's flux. You also observe a parallax shift for this star of 0.042 arcseconds. What is the luminosity of this star as a multiple of the Sun's luminosity L⊙. [Hint: use the flux formula in the form of a ratio, along with one other formula. Express your answer as a multiple of the Sun's luminosity---e.g., 150 L⊙---entering only that multiple (e.g., you would enter 150).]arrow_forwardAn O8 V star has an apparent visual magnitude of +5. Use the method of spectroscopic parallax to estimate the distance to the star (in pc). (Hints: Refer to one of the H–R diagrams in the chapter, and use the magnitude–distance formula, d = 10(mV − MV + 5)/5 where d is the distance in parsecs, mV and MV are the apparent and absolute visual magnitude respectively.)arrow_forward
- 12: A 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) Answer: 36.854 13:This 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. Please answer question 13 thank you.arrow_forwardStar 1 and star 2 have the same V-magnitude, V = 7.5. However, they have different B-magnitudes, B1 = 7.2 and B2 = 8.5. If star 2 has a distance that is 10 times further than star 1, what are the luminosity ratios, L1/L2, in both B- and V-bands?arrow_forwardLet us imagine that the spectrum of a star is collected and we find the absorption line of Hydrogen-Alpha (the deepest absorption line of hydrogen in the visible part of the electromagnetic spectrum) to be observed at 656.5 nm instead of 656.3 nm as measured in a lab here on Earth. What is the velocity of this star in m/s? (Hint: speed of light is 3*10^8 m/s; leave the units off of your answer) Question 4 of 7 A Moving to another question will save this response. 1 6:59 & backsarrow_forward
- I need the answer as soon as possiblearrow_forwardTwo stars (a and b) in a binary system have apparent V-band magnitudes of 8.0 and 8.4 mag, and B-V colour indices of 0.3 and -0.5 mag, respectively. (a) Which star is brightest in the V-band? (b) Which star is brightest in the B-band? (c) Which star would appeal bluer to the naked eye? (d) What is the ratio of monochromatic fluxes of the stars in the B-band? (e) What is the total apparent magnitude of the system in the V-band (assuming it is unresolved)?arrow_forwardA star with a radius 1.7 times that of the Sun has a surface temperature T=10,000 K. Calculate the luminosity of this star and express your answer in units of the Solar luminosity (the Solar luminosity = 3.84 x 1026 W and the Solar radius = 7 x %3D 108 m). Choose the option below that most closely matches your answer. Select one: а. 20 O b. 100. O C. 26. O d. 5. O e. 1000arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Stars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage LearningFoundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Stars and Galaxies (MindTap Course List)
Physics
ISBN:9781337399944
Author:Michael A. Seeds
Publisher:Cengage Learning
Foundations of Astronomy (MindTap Course List)
Physics
ISBN:9781337399920
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning