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 23, Problem 16Q
To determine
Whether or not the various Hubble types of galaxies represent some sort of evolutionary sequence.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Identify a feature of the Whirlpool Galaxy that is visible in all several types of light. Explain what this means
Estimate the age of the universe for a Hubble constant of (a)50km/s/Mpc, (b) 75km/s/Mpc, and (c) 100 km/s/Mpc. On the basis of the answers, explain how the ages of globular clusters could be used to put a limit on the maximum value of the Hubble constant.
Suppose you have obtained spectra of several galaxies and have measured the observed wavelength of the H-Alpha line (rest wavelength = 656.3 nm) to be
Galaxy 1: 658.1 nm.
Galaxy 2: 667.1 nm.
Galaxy 3: 677.6 nm.
Calculate the radial velocity of each of these galaxies.
Chapter 23 Solutions
Universe: Stars And Galaxies
Ch. 23 - Prob. 1QCh. 23 - Prob. 2QCh. 23 - Prob. 3QCh. 23 - Prob. 4QCh. 23 - Prob. 5QCh. 23 - Prob. 6QCh. 23 - Prob. 7QCh. 23 - Prob. 8QCh. 23 - Prob. 9QCh. 23 - Prob. 10Q
Ch. 23 - Prob. 11QCh. 23 - Prob. 12QCh. 23 - Prob. 13QCh. 23 - Prob. 14QCh. 23 - Prob. 15QCh. 23 - Prob. 16QCh. 23 - Prob. 17QCh. 23 - Prob. 18QCh. 23 - Prob. 19QCh. 23 - Prob. 20QCh. 23 - Prob. 21QCh. 23 - Prob. 22QCh. 23 - Prob. 23QCh. 23 - Prob. 24QCh. 23 - Prob. 25QCh. 23 - Prob. 26QCh. 23 - Prob. 27QCh. 23 - Prob. 28QCh. 23 - Prob. 29QCh. 23 - Prob. 30QCh. 23 - Prob. 31QCh. 23 - Prob. 32QCh. 23 - Prob. 33QCh. 23 - Prob. 34QCh. 23 - Prob. 35QCh. 23 - Prob. 36QCh. 23 - Prob. 37QCh. 23 - Prob. 38QCh. 23 - Prob. 39QCh. 23 - Prob. 40QCh. 23 - Prob. 41QCh. 23 - Prob. 42QCh. 23 - Prob. 43QCh. 23 - Prob. 44QCh. 23 - Prob. 45QCh. 23 - Prob. 46QCh. 23 - Prob. 47QCh. 23 - Prob. 48QCh. 23 - Prob. 49QCh. 23 - Prob. 50QCh. 23 - Prob. 51QCh. 23 - Prob. 52QCh. 23 - Prob. 53QCh. 23 - Prob. 54QCh. 23 - Prob. 55QCh. 23 - Prob. 56QCh. 23 - Prob. 57Q
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
- If a galaxy has a radial velocity of 21,641 km/s, what is its expected distance from the Hubble Law? Assume that the Hubble Constant is 71 km/s/Mpc. Answer in Mpcarrow_forwardIf the active core of a galaxy contains a black hole of 106 M, what will the orbital period be for matter orbiting the black hole at a distance of 0.23 AU? Hint: Use the formula for circular velocity, V. GM V hrarrow_forwardFigure 2 shows the "rotation curve" of NGC 2742. It plots the “radial velocity (V)" (how fast material is moving either toward or away from us) that is measured for objects at different distances (R = radius") from the center of the galaxy. The center of the galaxy is at 0 kpc (kiloparsecs) with a speed of 9 km/sec away from us. (These velocities have been corrected for the observed tilt of the galaxy and represent true orbital velocities of the stars and gas.) 200 100 U4779 -100 As you can see, one side of the galaxy is moving with a negative velocity (spinning toward us), while the other side has a positive velocity (spinning away from us). Using Newton's gravity equation, we will be able to determine the gravitational mass of the entire galaxy and how the mass varies versus distance from the galaxy's center. -200 -8 8 -4 Radius (kpc) Read the following text carefully and follow the instructions: Select five radii spaced evenly from 0-10 kpc across the galaxy. Your selections should…arrow_forward
- An important part of the lifecycle of galaxies like the Milky Way is the self regulation of formation of future generations of stars. Which statement best describes this process? A) Massive stars explode as Supernovae, heating nearby gas which then can't form stars, and even forcing the gas out of the galaxy in asuperbubble. B) Low mass stars like our Sun explode as Supernovae, heating nearby gas which then can't form stars, and even forcing the gas out the galaxy in asuperbubble. C) Stars fuse new elements in their cores which mix with nearby gas clouds, preventing the collapse of the clouds and hence stopping new starformation. D) The stars lock up material in their cores (like White Dwarf and Neutron Stars) meaning they can act as gravitational seeds for future starformation.arrow_forwardHow astronomers determine the distance of a galaxy? Explain.arrow_forwardA galaxy's rotation curve is a measure of the orbital speed of stars as a function of distance from the galaxy's centre. The fact that rotation curves are primarily flat at large galactocen- tric distances (vrot(r) ~ constant) is the most common example of why astronomer's believe dark matter exists. Let's work out why! Assuming that each star in a given galaxy has a circular orbit, we know that the accelera- tion due to gravity felt by each star is due to the mass enclosed within its orbital radius r and equal to v?/r. Here, ve is the circular orbit velocity of the star. (a) Show that the expected relationship between ve and r due to the stellar halo (p(r) xr-3.5) does not produce a flat rotation curve. (b) Show that a p(r) ∞ r¯² density profile successfully produces a flat ro- tation curve and must therefore be the general profile that dark matter follows in our galaxy.arrow_forward
- Globular clusters revolve around the Galaxy in highly elliptical orbits. Where would you expect the clusters to spend most of their time? (Think of Kepler’s laws.) At any given time, would you expect most globular clusters to be moving at high or low speeds with respect to the center of the Galaxy? Why? (If you would like to learn more about globular clusters, read Section 22.2 of the book, though it is not necessary to answer this question)arrow_forwardwhy are the shells visible around some elliptical galaxies significant?arrow_forwardThe time for a galaxy to cross from one side of a cluster to the other is called the crossing time. Find the crossing time for a galaxy moving at speed v to cross a cluster with a diameter d. Express you answer in gigayears, using one decimal place. Values: v = 849 km/s d = 1.3 Mpcarrow_forward
- Assume that an average globular cluster is 25 pc in diameter. If you observe a galaxy that contains globular clusters that are 6 arc seconds in diameter, how far away is the galaxy?arrow_forwardWhen comparing two isolated spiral galaxies that have the same apparent brightness, but rotate at different rates, what can you say about their relative luminosity?arrow_forward
arrow_back_ios
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 LearningAstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax
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
Astronomy
Physics
ISBN:9781938168284
Author:Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher:OpenStax