Foundations of Astronomy (MindTap Course List)
14th Edition
ISBN: 9781337399920
Author: Michael A. Seeds, Dana Backman
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 10, Problem 4P
To determine
The fraction of photons survived in cloud.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Please answer within 90 minutes.
The Stefan-Boltzmann equation can be used to estimate the size of asteroids. "Sigma," the Stefan-Boltzmann constant, is 5.67 x 10 Watts/m²K. If you want to abbreviate Plus 1.1415
You measure the infrared emission from an asteroid and conclude that it has a temperature of 249 K. Using rader you find the distance, and are then able to use your infrared brightness to determine a luminosity of 7.21E+12
Watts. If you assume the asteroid is roughly spherical, what is its radius in meters?
CHECK ANSWER
A)The star 58 Eridani is a feint but naked-eye star similar to the Sun. Suppose that you are observing this star in the night sky without a telescope. Ignoring any interstellar extinction or atmospheric absorption, approximately how many photons per second arrive at your retina? Show all steps in calculation .
B) The Mid-infared Instrument (MIRI , camera and spectrograph ) on the James Webb Space Telescope operates in the band 5-28 µm . For 58 Eridani , approximatley how many photons per second can be used by this instrument ? Assume that MIRI takes all the photons from the full JWST mirror . Show all steps in calcultation .
Describe breifly two or three other factors which play a role in determining the sensetivitu of an instrument such as MIRI ?
Chapter 10 Solutions
Foundations of Astronomy (MindTap Course List)
Ch. 10 - Prob. 1RQCh. 10 - Prob. 2RQCh. 10 - Prob. 3RQCh. 10 - Prob. 4RQCh. 10 - Prob. 5RQCh. 10 - Prob. 6RQCh. 10 - Prob. 7RQCh. 10 - Prob. 8RQCh. 10 - Prob. 9RQCh. 10 - Prob. 10RQ
Ch. 10 - Prob. 11RQCh. 10 - Prob. 12RQCh. 10 - Prob. 13RQCh. 10 - Why is the ISM transparent at near-infrared and...Ch. 10 - Prob. 15RQCh. 10 - Prob. 16RQCh. 10 - Prob. 17RQCh. 10 - Prob. 18RQCh. 10 - Prob. 19RQCh. 10 - Prob. 20RQCh. 10 - Prob. 21RQCh. 10 - Name two processes (or objects) that remove...Ch. 10 - Prob. 23RQCh. 10 - Prob. 24RQCh. 10 - Prob. 25RQCh. 10 - Prob. 1PCh. 10 - Prob. 2PCh. 10 - Prob. 3PCh. 10 - Prob. 4PCh. 10 - The number density of air in a childs balloon is...Ch. 10 - Calculate the frequency in megahertz (MHz) of the...Ch. 10 - Prob. 7PCh. 10 - Prob. 8PCh. 10 - Prob. 9PCh. 10 - Prob. 10PCh. 10 - Prob. 1SOPCh. 10 - Prob. 2SOPCh. 10 - Prob. 1LTLCh. 10 - Prob. 2LTLCh. 10 - Prob. 3LTLCh. 10 - Prob. 4LTLCh. 10 - Prob. 5LTL
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
- At the average density of the interstellar medium, 1 atom per cm3, how big a volume of material must be used to make a star with the mass of the Sun? What is the radius of a sphere this size? Express your answer in light-years.arrow_forwardWhy would we not expect to detect X-rays from a disk of matter about an ordinary star?arrow_forwardWould you expect to be able to detect an H II region in X-ray emission? Why or why not? (Hint: You might apply Wien’s law)arrow_forward
- A cloud of mean number density n ~ 3000 cm-3 and radius 3 pc has an ionising source with luminosity at 13.6 eV of L13.6eV = 2.18 x 109 erg s- at the centre. (a) What is the size of the HII region in pe? [og = 2 x 10-13 cms-]. %3D (b) What assumptions are involved in part a) (c) Discuss why the HII region will drive a shock into the rest of the cloud, and calculate the post-shock density. (d) Show why this HII region will destroy the cloud.arrow_forward9arrow_forwardQuestion 2: apparent magnitude my 1 = 305.9, b = −44.9 and is d=4.5 kpc from the Sun. a.) The integrated light from the Milky Way globular cluster NGC 104 has an 4.03 mag and absolute magnitude My -9.52 mag. It is located at b.) = = Estimate the amount of extinction between the Sun and 47 Tucanae in magnitudes. What does this value of extinction mean for the amount of attenuation by dust between Earth and NGC 104?.arrow_forward
- You are the leader of the international Event Horizon Telescope, a collaboration of radio astronomers who want to take a picture of the black hole at the center of the Milky Way (Sag. A*). That black hole has a mass of about 4.1 million solar masses and is about 8 kpc away. If you are observing with a radio wavelength of about 1 mm, what effective diameter of your radio interferometric array is needed in order to just resolve the diameter of the Sag. A* black hole event horizon. (Assume the black hole is non-spinning, so its diameter is twice the event horizon radius.) Express your answer as a multiple of the Earth's radius. [Hint: you will need to recall and combine three formulas introduced throughout this course, including one about how big a black hole is, one about the criterion for resolving objects, and another that relates distance, sizes, and angles.] There really is an Event Horizon Telescope, and they are responsible for the first image of a black hole in the galaxy M87…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_forwardConsider the image above of the Cassiopeia A (Cas A) supernova remnant. The supernova explosion that caused this remnant was observed on earth about 300 years ago. It is about 3000 pc away. Since that time, the shockwave from the supernova has expanded to form the roughly spherical cloud pictured above. From the center point to the edge of the cloud is about 3 pc. Compute the angular diameter of the Cas A supernova remnant as viewed from Earth. Express your answer in arcminutes.arrow_forward
- 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-+ 1011arrow_forwardThere are several spectral features that can be used to characterise galax- ies, including the Hydrogen-a emission at 656.3 nm and the Hydrogen- emission at 486.8 nm. For the Hydrogen-a emission, the spectrograph on the FET just gives sufficient resolution to resolve the emission line, which has a width of 100 km s¹. Calculate the ruling density necessary to observe the Hydrogen- ß emission line at the same resolution, if the observations are taken in first order and in 1-arcsecond seeing.arrow_forwardA cloud of gas has a temperature of 5,000 K. Estimate the width of the hydrogen H-alpha line with an intrinsic wavelength λ = 656 nm. (Note: the typical velocity of hydrogen atoms in a gas with temperature T is about (kT/mH)1/2, where k is Boltzmann constant and mH is the mass of a hydrogen atom, which is approximately the mass of a proton).arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Stars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage Learning
AstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax
Horizons: Exploring the Universe (MindTap Course ...PhysicsISBN:9781305960961Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Stars and GalaxiesPhysicsISBN:9781305120785Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Foundations of Astronomy (MindTap Course List)
Physics
ISBN:9781337399920
Author:Michael A. Seeds, Dana Backman
Publisher: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
Horizons: Exploring the Universe (MindTap Course ...
Physics
ISBN:9781305960961
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
Stars and Galaxies
Physics
ISBN:9781305120785
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning