EBK COSMIC PERSPECTIVE, THE
8th Edition
ISBN: 8220101465108
Author: Voit
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 19, Problem 38EAP
Discovering the Structure of the Milky Way. The stoly of how we came to learn the structure of the Milky Way (see the Special ibpic on page 582) is an excellent example of how science progresses. What features of the Milky Ways appearance in our sky led scientists to conclude that it is much wider than it is thick? Why did they originally believe that the Sun was near the Milky Way’s center? What key observations forced scientists to change their views about the location of the Sun within the Milky Way?
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
Estimating the mass of the Milky Way
a) Assuming the Sun moves in a circular orbit of radius 8 kiloparsecs around the center of the Milky Way, and that its orbital speed
is 220 km/s, calculate how many years it takes the Sun to complete one orbit of the Galaxy. Remember to convert kiloparsecs to
kilometers.
b) Using the modified form of Kepler's third law (introduced in Lecture 13, for measuring the combined masses of binary stars),
R³
m+ M = estimate the mass of the Milky Way enclosed within 8 kpc (Sun's orbit radius). The mass of the Milky Way inside
p²
I
the Sun's orbit can be represented as a single mass (M) located at its center, and the mass of the Sun (m) can be considered
infinitesimally small compared to the Milky Way's (i.e., m < M).
c) Is this estimate of the Milky Way's mass an upper or lower limit? Explain your reasoning.
Try Now
...
....
Listed below are some distances from Earth to other objects in the Milky Way galaxy. Convert each
distance to light-years. (Each of these distances is less than one light-year. For an added challenge,
convert each distance to light minutes or light seconds.)
1.
The distance from Earth to the Moon is about 384,400 km. How many light-years is this?
2.
The distance from Earth to Mars is about 784,000,000 km. How many light-years is this?
3.
The distance from Earth to Pluto is about 5,750,000,000 km. How many light-years is this?
The Milky Way grew through merging with many smaller galaxies. What are the observational signatures of this process?
O The motion of old stars in the bulge and halo of our galaxy are randomly orientated, meaning they were formed from collisions of small,
accreted, galaxies all on different paths.
O The ordered motion of the bulge / halo stars means that they came from many objects.
The random motions of stars in the disk means it was formed from collisions of small, accreted, galaxies.
O The motion of young stars in the disk are all in the same direction, meaning they came in as seperate objects.
Chapter 19 Solutions
EBK COSMIC PERSPECTIVE, THE
Ch. 19 - Prob. 1VSCCh. 19 - Prob. 2VSCCh. 19 - Prob. 3VSCCh. 19 - Prob. 4VSCCh. 19 - Prob. 5VSCCh. 19 - Prob. 6VSCCh. 19 - Prob. 1EAPCh. 19 - Prob. 2EAPCh. 19 - Prob. 3EAPCh. 19 - Prob. 4EAP
Ch. 19 - Prob. 5EAPCh. 19 - Prob. 6EAPCh. 19 - Prob. 7EAPCh. 19 - Prob. 8EAPCh. 19 - Prob. 9EAPCh. 19 - Prob. 10EAPCh. 19 - Prob. 11EAPCh. 19 - Prob. 12EAPCh. 19 - Prob. 13EAPCh. 19 - Prob. 14EAPCh. 19 - Prob. 15EAPCh. 19 - Prob. 16EAPCh. 19 - Prob. 17EAPCh. 19 - Does It Make Sense? Decitie whether the statement...Ch. 19 - Prob. 19EAPCh. 19 - Prob. 20EAPCh. 19 - Prob. 21EAPCh. 19 - Prob. 22EAPCh. 19 - Prob. 23EAPCh. 19 - Prob. 24EAPCh. 19 - Prob. 25EAPCh. 19 - Prob. 26EAPCh. 19 - Prob. 27EAPCh. 19 - Prob. 28EAPCh. 19 - Prob. 29EAPCh. 19 - Prob. 30EAPCh. 19 - Choose the best answer to each of the following....Ch. 19 - Prob. 32EAPCh. 19 - Prob. 33EAPCh. 19 - Prob. 34EAPCh. 19 - Prob. 35EAPCh. 19 - Prob. 36EAPCh. 19 - Prob. 37EAPCh. 19 - Discovering the Structure of the Milky Way. The...Ch. 19 - Prob. 39EAPCh. 19 - Prob. 40EAPCh. 19 - Prob. 41EAPCh. 19 - Prob. 42EAPCh. 19 - Prob. 43EAPCh. 19 - Prob. 44EAPCh. 19 - Prob. 45EAPCh. 19 - Prob. 46EAPCh. 19 - Prob. 47EAPCh. 19 - Prob. 48EAPCh. 19 - Prob. 49EAPCh. 19 - Prob. 50EAPCh. 19 - Prob. 51EAPCh. 19 - Prob. 52EAPCh. 19 - Prob. 53EAPCh. 19 - Prob. 54EAPCh. 19 - Prob. 55EAPCh. 19 - Prob. 56EAPCh. 19 - Prob. 57EAPCh. 19 - Prob. 58EAPCh. 19 - Prob. 59EAP
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
- Suppose we look at two distant galaxies: Galaxy 1 is twice as far away as Galaxy 2. In this case, A. Galaxy 1 must be twice as big as Galaxy 2. B. we are seeing Galaxy 1 as it looked at an earlier time in the history of the universe than Galaxy 2. C. we are seeing Galaxy 1 as it looked at a later time in the history of the universe than Galaxy 2. D. Galaxy 2 must be twice as old as Galaxy 1.arrow_forwardHubble's First Attempt. Edwin Hubble's first attempt to measure the universe's expansion rate was flawed because the standard candles he was using were not properly calibrated. Look at (Figure 1) a.Estimate the value of Ho corresponding to the solid line in the figure. Express your answer kilometers per second per million light-years to two significant figures. b.What is the approximate age of the universe indicated by that erroneous value of Ho? Express your answer in years to one significant figure.arrow_forwardAs we discussed, clouds are made of a great many small drops. Really - a great many. Imagine a liquid cloud that fills a volume of 1 km3. The clouds contains 100 drops per cubic centimeter; for the sake of argument assume that each is 10 microns (micrometers) in radius. A. How many drops does the cloud contain? Compare this to a big number - say, the number of stars in the galaxy. B. What mass of water does the cloud contain? Compare this to something big - elephants, trucks, that sort of thing. C. What fraction of the cloud volume is filled with condensed water? One way to approach this is to compare the density of the suspended liquid water to the density of the surrounding air. D. How many 1 mm drizzle drops could you make from all the cloud drops? E. How much energy was released when this water condensed from vapor to liquid? If the water condensed in 20 minutes (a reasonable lifetime for a small cloud), what was the (energy per time)? powerarrow_forward
- Which of the following statements best describes our galaxy, the Milky Way? O A bulge dominated system, with little or no disk, approximately 27,000 light years across. A disk 100,000 lightyears across filled with gas and stars, with a bulge of older stars in the galaxy centre. A disk 27,000 light years across with a bulge of gas and newly formed stars in the galaxy centre. O A spherical (elliptical) galaxy, 100,000 lightyears across, with no gas and no new stars.arrow_forwardImagine that you have achieved immortality and you used it to travel outside of the Milky Way (you will be leaving today and you will be traveling with the speed of 1/10th of the speed of light). Describe how the Milky Way would look from the outside if you could watch it for the next 100 billion years.arrow_forward2. A galaxy cluster has a galaxy behind it whose image we see as being smeared out and curved, with an angular radius of curvature on the sky of θE. The background galaxy is at redshift zgal and the cluster is at zclust. What is the mass of the cluster in solar masses? Give your response in scientific notation with one decimal place. (The Hubble constant is of course 70 km/s/Mpc, and you can assume the Hubble law for these low redshifts). Values: zgal = 0.11 zclust = 0.07 θE = 117.4 arcsecondsarrow_forward
- Stars form in the Milky Way at a rate of about 1 solar mass per year. At this rate, how long would it take for all the interstellar gas in the Milky Way to be turned into stars if there were no fresh gas coming in from outside? How does this compare to the estimated age of the universe, 14 billion years? What do you conclude from this?arrow_forwardHuman civilization is about 10,000 years old as measured by the development of agriculture. If your telescope collects starlight tonight that has been traveling for 10,000 years, is that star inside or outside our Milky Way Galaxy? Is it likely that the star has changed much during that time?arrow_forwardBriefly describe the main parts of our Galaxy.arrow_forward
- Suppose the Milky Way was a band of light extending only halfway around the sky (that is, in a semicircle). What, then, would you conclude about the Sun’s location in the Galaxy? Give your reasoning.arrow_forwardExplain why we see the Milky Way as a faint band of light stretching across the sky.arrow_forward
arrow_back_ios
arrow_forward_ios
Recommended textbooks for you
Stars and GalaxiesPhysicsISBN:9781305120785Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
AstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax
Stars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage Learning
Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Stars and Galaxies
Physics
ISBN:9781305120785
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
Astronomy
Physics
ISBN:9781938168284
Author:Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: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
General Relativity: The Curvature of Spacetime; Author: Professor Dave Explains;https://www.youtube.com/watch?v=R7V3koyL7Mc;License: Standard YouTube License, CC-BY