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 20, Problem 56Q
To determine
The two processes that account for the bright light given off by
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Observations show that the gas ejected from SN 1987A is moving at
about 10,000 km/s. How long will it take to travel one astronomical
unit? One parsec? (Note that 1 AU equals 1.5 × 108 km, and 1 pc
equals 3.1 × 10¹³ km.)
Explain why the sky is blue and how that relates to reflection nebulae.
1 Solar constant, Sun, and the 10 pc distance!
The luminosity of Sun is + 4- 1026 W - 4- 1033ergs-1, The Sun is located at a distance of
m from the Earth. The Earth receives a radiant flux (above its atmosphere) of F = 1365W m- 2, also known as
the solar constant. What would have been the Solar contact if the Sun was at a distance of 10 pc ?
1AU 1 1.5-+ 1011
Chapter 20 Solutions
Universe: Stars And Galaxies
Ch. 20 - Prob. 1QCh. 20 - Prob. 2QCh. 20 - Prob. 3QCh. 20 - Prob. 4QCh. 20 - Prob. 5QCh. 20 - Prob. 6QCh. 20 - Prob. 7QCh. 20 - Prob. 8QCh. 20 - Prob. 9QCh. 20 - Prob. 10Q
Ch. 20 - Prob. 11QCh. 20 - Prob. 12QCh. 20 - Prob. 13QCh. 20 - Prob. 14QCh. 20 - Prob. 15QCh. 20 - Prob. 16QCh. 20 - Prob. 17QCh. 20 - Prob. 18QCh. 20 - Prob. 19QCh. 20 - Prob. 20QCh. 20 - Prob. 21QCh. 20 - Prob. 22QCh. 20 - Prob. 23QCh. 20 - Prob. 24QCh. 20 - Prob. 25QCh. 20 - Prob. 26QCh. 20 - Prob. 27QCh. 20 - Prob. 28QCh. 20 - Prob. 29QCh. 20 - Prob. 30QCh. 20 - Prob. 31QCh. 20 - Prob. 32QCh. 20 - Prob. 33QCh. 20 - Prob. 34QCh. 20 - Prob. 35QCh. 20 - Prob. 36QCh. 20 - Prob. 37QCh. 20 - Prob. 38QCh. 20 - Prob. 39QCh. 20 - Prob. 40QCh. 20 - Prob. 41QCh. 20 - Prob. 42QCh. 20 - Prob. 43QCh. 20 - Prob. 44QCh. 20 - Prob. 45QCh. 20 - Prob. 46QCh. 20 - Prob. 47QCh. 20 - Prob. 48QCh. 20 - Prob. 49QCh. 20 - Prob. 50QCh. 20 - Prob. 51QCh. 20 - Prob. 52QCh. 20 - Prob. 53QCh. 20 - Prob. 54QCh. 20 - Prob. 55QCh. 20 - Prob. 56QCh. 20 - Prob. 57QCh. 20 - Prob. 58QCh. 20 - Prob. 59QCh. 20 - Prob. 60QCh. 20 - Prob. 61QCh. 20 - Prob. 62QCh. 20 - Prob. 63QCh. 20 - Prob. 64QCh. 20 - Prob. 65QCh. 20 - Prob. 66QCh. 20 - Prob. 67QCh. 20 - Prob. 68QCh. 20 - Prob. 69QCh. 20 - Prob. 70QCh. 20 - Prob. 71QCh. 20 - Prob. 72QCh. 20 - Prob. 73QCh. 20 - Prob. 74QCh. 20 - Prob. 75Q
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
- What is the acceleration of gravity at the surface of the star that became SN 1987A? How does this g compare to that at the surface of Earth? The mass was 20 times that of the Sun and the radius was 41 times that of the Sun.arrow_forwardWhat was the escape velocity from the surface of the SN 1987A progenitor star? How much greater is it than the escape velocity from Earth? The mass was 20 times that of the Sun and the radius was 41 times that of the Sun.arrow_forwardIf the hottest star in the Carina Nebula has a surface temperature of 51,000 K, at what wavelength (in nm) does it radiate the most energy? Hint: Use Wien's law: ?max = 2.90 ✕ 106 nm · K T How does that compare with 91.2 nm, the wavelength of photons with just enough energy to ionize hydrogen? -The wavelength calculated above is shorter than 91.2 nm. Photons at this calculated wavelength will have more than enough energy to ionize hydrogen. -The wavelength calculated above is longer than 91.2 nm. Photons at this calculated wavelength will have more than enough energy to ionize hydrogen. -The wavelength calculated above is shorter than 91.2 nm. Photons at this calculated wavelength will not have enough energy to ionize hydrogen. -The wavelength calculated above is longer than 91.2 nm. Photons at this calculated wavelength will not have enough energy to ionize hydrogen.arrow_forward
- The ring around SN 1987A (see the figures below) initially became illuminated when energetic photons from the supernova interacted with the material in the ring. The radius of the ring is approximately 0.75 light-year from the supernova location. How long (in years) after the supernova did the ring become illuminated?arrow_forwardwhy do dark streaks appear in visible light images of the Trifid nebula, but appear bright in an infared imagearrow_forwardWhat is the relationship between the color of a reflection nebula and the color of the star that illuminates it?arrow_forward
- H II regions can exist only if there is a nearby star hot enough to ionize hydrogen. Hydrogen is ionized only by radiation with wavelengths shorter than 91.2 nm. What is the temperature of a star that emits its maximum energy at 91.2 nm? (Use Wien’s law from Radiation and Spectra.) Based on this result, what are the spectral types of those stars likely to provide enough energy to produce H II regions?arrow_forwardWhat was the average density of the star that became SN 1987A? How does it compare to the average density of Earth? The mass was 20 times that of the Sun and the radius was 41 times that of the Sun.arrow_forwardWhat causes reddening of starlight? Explain how the reddish color of the Sun’s disk at sunset is caused by the same process.arrow_forward
- Look at the four stages shown in Figure 21.8. In which stage(s) can we see the star in visible light? In infrared radiation? Figure 21.8 Formation of a Star. (a) Dense cores form within a molecular cloud. (b) A protostar with a surrounding disk of material forms at the center of a dense core, accumulating additional material from the molecular cloud through gravitational attraction. (c) A stellar wind breaks out but is confined by the disk to flow out along the two poles of the star. (d) Eventually, this wind sweeps away the cloud material and halts the accumulation of additional material, and a newly formed star, surrounded by a disk, becomes observable. These sketches are not drawn to the same scale. The diameter of a typical envelope that is supplying gas to the newly forming star is about 5000 AU. The typical diameter of the disk is about 100 AU or slightly larger than the diameter of the orbit of Pluto.arrow_forwardWhy do nebulae near hot stars look red? Why do dust clouds near stars usually look blue?arrow_forwardIf the Sun were a member of the cluster NGC 2264, would it be on the main sequence yet? Why or why not?arrow_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 Learning
AstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax
Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Stars and GalaxiesPhysicsISBN:9781305120785Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Horizons: Exploring the Universe (MindTap Course ...PhysicsISBN:9781305960961Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Stars and Galaxies (MindTap Course List)
Physics
ISBN:9781337399944
Author:Michael A. Seeds
Publisher:Cengage Learning
Astronomy
Physics
ISBN:9781938168284
Author:Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher:OpenStax
Foundations of Astronomy (MindTap Course List)
Physics
ISBN:9781337399920
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
Stars and Galaxies
Physics
ISBN:9781305120785
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
Horizons: Exploring the Universe (MindTap Course ...
Physics
ISBN:9781305960961
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning