Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 26, Problem 18E
Why can we not determine distances to galaxies by the same method used to measure the parallaxes of stars?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
The center of our Galaxy is about 7500 parsecs from Earth. What would be the parallax angle of a star near the center of the Galaxy? Could this angle be measured with current technology?
The Hubble Law, equation (D), can be used to determine the age of the universe. Using your average valueof H, calculate the recessional velocity of a galaxy of a galaxy which is 800 Mpc away.Velocity of a galaxy 800 Mpc away: _______________________________km/sec
Can we measure distances to other galaxies using parallax? Why or why not?
Chapter 26 Solutions
Astronomy
Ch. 26 - Describe the main distinguishing features of...Ch. 26 - Why did it take so long for the existence of other...Ch. 26 - Explain what the mass-to-light ratio is and why it...Ch. 26 - If we now realize dwarf ellipticals are the most...Ch. 26 - What are the two best ways to measure the distance...Ch. 26 - What are the two best ways to measure the distance...Ch. 26 - Why is Hubble’s law considered one of the most...Ch. 26 - What does it mean to say that the universe is...Ch. 26 - Was Hubble’s original estimate of the distance to...Ch. 26 - Does an elliptical galaxy rotate like a spiral...
Ch. 26 - Why does the disk of a spiral galaxy appear dark...Ch. 26 - What causes the largest mass-to-light ratio: gas...Ch. 26 - What is the most useful standard bulb method for...Ch. 26 - When comparing two isolated spiral galaxies that...Ch. 26 - If all distant galaxies are expanding away from...Ch. 26 - Is the Hubble constant actually constant?Ch. 26 - Where might the gas and dust (if any) in an...Ch. 26 - Why can we not determine distances to galaxies by...Ch. 26 - Which is redder-a spiral galaxy or an elliptical...Ch. 26 - Suppose the stars in an elliptical galaxy all...Ch. 26 - Starting with the determination of the size of...Ch. 26 - Suppose the Milky Way Galaxy were truly isolated...Ch. 26 - Suppose you were Hubble and Humason, working on...Ch. 26 - What does it mean if one elliptical galaxy has...Ch. 26 - Based on your analysis of galaxies in Table 26.1,...Ch. 26 - Can a higher mass-to-light ratio mean that there...Ch. 26 - According to Hubble’s law, what is the recessional...Ch. 26 - A cluster of galaxies is observed to have a...Ch. 26 - Suppose we could measure the distance to a galaxy...Ch. 26 - Calculate the mass-to-light ratio for a globular...Ch. 26 - Calculate the mass-to-light ratio for a luminous...
Additional Science Textbook Solutions
Find more solutions based on key concepts
When you stand on Earth, your feet push against it with a force equal to your weight. Why doesn’t Earth acceler...
University Physics Volume 1
What is the average kinetic energy in joules of hydrogen atoms on the 5500 surface of the Sun? (b) What is the...
University Physics Volume 2
A thin plate has a round hole whose diameter in its rest frame is D. The plate is parallel to the ground and mo...
Modern Physics
1.50 An acre has a length of one furlong ( mi) and a width one-tenth of its length. (a) How many acres are in a...
University Physics with Modern Physics (14th Edition)
When the momentum of an object or system of objects does not change with time, the momentum of the object or sy...
Tutorials in Introductory Physics
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
- When 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_forwardWhat is the most useful standard bulb method for determining distances to galaxies?arrow_forwardBased on your analysis of galaxies in Table 26.1, is there a correlation between the population of stars and the quantity of gas or dust? Explain why this might be.arrow_forward
- Assume that the Sun orbits the center of the Galaxy at a speed of 220 km/s and a distance of 26,000 lightyears from the center. A. Calculate the circumference of the Sun’s orbit, assuming it to be approximately circular. (Remember that the circumference of a circle is given by 2pR, where R is the radius of the circle. Be sure to use consistent units. The conversion from light-years to km/s can be found in an online calculator or appendix, or you can calculate it for yourself: the speed of light is 300,000 km/s, and you can determine the number of seconds in a year.) B. Calculate the Sun’s period, the “galactic year.” Again, be careful with the units. Does it agree with the number we gave above?arrow_forwardThe best parallaxes obtained with Hipparcos have an accuracy of 0.001 arcsec. If you want to measure the distance to a star with an accuracy of 10%, its parallax must be 10 times larger than the typical error. How far away can you obtain a distance that is accurate to 10% with Hipparcos data? The disk of our Galaxy is 100,000 light-years in diameter. What fraction of the diameter of the Galaxy’s disk is the distance for which we can measure accurate parallaxes?arrow_forwardAssume that we have measured the distance to a close by galaxy, with apparent magnitude m1 = 6, to be d1 = 1Mpc. We now assume that all galaxies are similar and have therefore the same intrinsic or absolute, luminosity. Then measuring the apparent magnitude of a second galaxy to be m2 = 11, estimate the distance to that galaxy. Please answer within 90 minutes.arrow_forward
- Astronomers recently claimed to have discovered the most distant galaxy known. How would they have determine this distance?arrow_forwardAn observational survey of distant galaxies is undertaken that involves measuring their distances using cepheid variables and red-shifts using spectroscopy. Explain how cepheid variables can be used to measure the distances to galaxies. A spectral line is observed whose wavelength in the laboratory is de length of this spectral line observed in each galaxy, Xo, is listed in the table, along with the distance, d, to the galaxy. Determine the red-shift and the recession velocity of each galaxy and tabulate your results by making a copy of the table and filling in the blank spaces. Sketch a Hubble diagram using your results and determine the value of the Hubble constant Ho in units of km s-1 Mpc. 650 nm. The wave- Galaxy 1 652.69 Galaxy 2 Galaxy 3 Galaxy 4 Galaxy 5 653.01 do (nm) d (Mpc) 658.54 662.18 681.63 17 19 54 77 200 v (km s-1)arrow_forwardWhat is the magnitude of the merger of two galaxies which have the magnitudes m1 and m2?arrow_forward
- Based on Figure 1 below, which galaxies are moving away from us the fastest? Velocity (km/sec) 2000 1500 1000 500 -500 10 F 20 Distance (Mpc) 30arrow_forwardAn astronomical image shows two objects that have the same apparent magnitude, i.e., the same brightness. However, spectroscopic follow up observations indicate that while one is a star that is within our galaxy, at a distance dgal away, and has the same luminosity as the Sun, the other is a quasar and has 100x the luminosity of the entire Milky Way galaxy. What is the distance to the quasar? (You may assume, for this rough calculation, that the Milky Way has 1011 stars and that they all have the luminosity as the Sun.) Give your response in Mpc. Value: dgal = 49 pcarrow_forwardhelparrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- AstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStaxStars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage LearningStars and GalaxiesPhysicsISBN:9781305120785Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
- Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage LearningPhysics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.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
Stars and Galaxies
Physics
ISBN:9781305120785
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
Foundations of Astronomy (MindTap Course List)
Physics
ISBN:9781337399920
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