21st Century Astronomy
6th Edition
ISBN: 9780393428063
Author: Kay
Publisher: NORTON
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 21, Problem 12QP
To determine
The scale factor keeps track of.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
When two galaxies collide, the stars inside them are not likely to be much affected, because the __________ stars is so large compared to their diameters. However, the _______ of stars and gas can be changed, altering the appearance of the galaxies. Astronomers have determined that such collisions are seen more often in ____________. When two galaxies of roughly equal size collide, astronomers call it a _______ of galaxies; but when a small galaxy collides with a much larger one, the process is called ___________. When a galaxy has a significant amount of its interstellar gas compressed by a collision, leading to the birth of many new stars, astronomers call it a __________ galaxy.
Which of the following might you expect to be an additional consequence of the fact that galaxies contain more mass than expected?A. The gravitational force between galaxies is greater than expected.B. Galaxies appear less bright than expected.C. Galaxies are farther away than expected.D. There are more galaxies than expected.
3. Suppose you measure the radial velocity of a galaxy to be 5,000 km/s. How far away is it?
Chapter 21 Solutions
21st Century Astronomy
Ch. 21.1 - Prob. 21.1CYUCh. 21.2 - Prob. 21.2CYUCh. 21.3 - Prob. 21.3ACYUCh. 21.3 - Prob. 21.3BCYUCh. 21.4 - Prob. 21.4CYUCh. 21 - Prob. 1QPCh. 21 - Prob. 2QPCh. 21 - Prob. 3QPCh. 21 - Prob. 4QPCh. 21 - Prob. 5QP
Ch. 21 - Prob. 6QPCh. 21 - Prob. 7QPCh. 21 - Prob. 8QPCh. 21 - Prob. 9QPCh. 21 - Prob. 10QPCh. 21 - Prob. 11QPCh. 21 - Prob. 12QPCh. 21 - Prob. 13QPCh. 21 - Prob. 14QPCh. 21 - Prob. 15QPCh. 21 - Prob. 16QPCh. 21 - Prob. 17QPCh. 21 - Prob. 18QPCh. 21 - Prob. 19QPCh. 21 - Prob. 20QPCh. 21 - Prob. 21QPCh. 21 - Prob. 23QPCh. 21 - Prob. 24QPCh. 21 - Prob. 25QPCh. 21 - Prob. 26QPCh. 21 - Prob. 27QPCh. 21 - Prob. 28QPCh. 21 - Prob. 29QPCh. 21 - Prob. 30QPCh. 21 - Prob. 31QPCh. 21 - Prob. 32QPCh. 21 - Prob. 33QPCh. 21 - Prob. 34QPCh. 21 - Prob. 35QPCh. 21 - Prob. 36QPCh. 21 - Prob. 37QPCh. 21 - Prob. 38QPCh. 21 - Prob. 39QPCh. 21 - Prob. 40QPCh. 21 - Prob. 41QPCh. 21 - Prob. 42QPCh. 21 - Prob. 43QPCh. 21 - Prob. 44QPCh. 21 - 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
- How many galaxies like our own would it take Laid edge-to-edge to reach the nearest galaxy? (Hint: See Problem 9.)arrow_forwardMost distances in the Galaxy are measured in light-years instead of meters. Why do you think this is the case?arrow_forwardHow many galaxies are there in the universe?arrow_forward
- The diameter of our disk-shaped galaxy, the Milky Way, is about 1.0×105light-years. The distance to the Andromeda galaxy, which is the spiral galaxynearest to the Milky Way, is about 2.5 million light-years. If a scale modelrepresents the Milky Way and Andromeda galaxies as dinner plates 20 cm indiameter, determine the distance between the centers of the two plates.arrow_forwardIndicate whether the following statements are true or false. (Select T-True, F-False. If the first is T and the rest F, enterTFFFFF). A) The three main classifications of galaxies are elliptical, spiral and prime.B) The mass of a spiral galaxy can be found from its rotational velocity. The greater the rotation, the greater the mass.C) Galaxies sometimes collide with each other.D) It wasn't until the 1920s that we knew the Milky Way was only one of many galaxies.E) Most galaxies are elliptical.F) The shorter the pulsation period of a Cepheid variable star, the more luminous it is.arrow_forwardWe know that dark matter must exist in galaxies. If not, many of the stars in a galaxy would ... a.Expand and go supernova due to the expansion of the Universe b.Fly away from the galaxy because the stars’ velocities are so large, and the galaxy would not have enough gravity to hold onto them c.Orbit the center of the galaxy normally d.Spiral in toward the center of the galaxy because most of the galaxy’s mass would be toward the centerarrow_forward
- Joaquin tells his science class that galaxies consist of gas, dust, and many planets. What is the most important component of galaxies Joaquin is missing in his descriptionarrow_forwardWhat happens when galaxies collide? A. Star collisions will be rare but the shapes of the galaxies will be largely distorted. B. The shapes of the galaxies will be largely distorted and many of the stars of one galaxy will collide with stars of the other galaxy. C. The shapes of the galaxies will be distorted and many stars will collide with stars of the other galaxy, as well as with other stars in the same galaxy. D. Star collisions will be rare and the two galaxies will just pass through each other without any changes. Is the answer A? Thank you!arrow_forwardDescribe the age and temperature of stars that make up spiral galaxies and their location.arrow_forward
arrow_back_ios
arrow_forward_ios
Recommended textbooks for you
Stars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage Learning
An Introduction to Physical SciencePhysicsISBN:9781305079137Author:James Shipman, Jerry D. Wilson, Charles A. Higgins, Omar TorresPublisher:Cengage Learning
Horizons: Exploring the Universe (MindTap Course ...PhysicsISBN:9781305960961Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage Learning
AstronomyPhysicsISBN: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
An Introduction to Physical Science
Physics
ISBN:9781305079137
Author:James Shipman, Jerry D. Wilson, Charles A. Higgins, Omar Torres
Publisher:Cengage Learning
Horizons: Exploring the Universe (MindTap Course ...
Physics
ISBN:9781305960961
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
Physics for Scientists and Engineers: Foundations...
Physics
ISBN:9781133939146
Author:Katz, Debora M.
Publisher:Cengage Learning
Astronomy
Physics
ISBN:9781938168284
Author:Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher:OpenStax