Let the number density (stars/volume) of stars be p. Take it to be uniform throughout theuniverse. Calculate the number of stars dN contained in a shell around the earth at adistance from R to R + dR, and calculate the total light intensity from the stars (assume allthe stars emit with the same power) in this shell.

Here is the step-by-step explanation:Given:Number density of stars =ρ (stars per unit…

Answered: Let the number density (stars/volume)…

Foundations of Astronomy (MindTap Course List)

14th Edition

ISBN:9781337399920

Author:Michael A. Seeds, Dana Backman

Publisher:Michael A. Seeds, Dana Backman

Chapter25: Astrobiology: Life On Other Worlds

Section: Chapter Questions

Problem 9P: The first radio broadcast was made on January 13, 1910. It was a live performance at New York Citys...

See similar textbooks

Similar questions

Suppose a star 1000 times brighter than our Sun (that is, emitting 1000 times the power) suddenly goes supernova. Using data from Table: (a) By what factor does its power output increase? (b) How many times brighter than our entire Milky Way galaxy is the supernova? (c) Based on your answers, discuss whether it should be possible to observe supernovas in distant galaxies. Note that there are on the order of 1011 observable galaxies, the average brightness of which is somewhat less than our own galaxy.
Small differences in the wavelengths in the sun’s spectrum are detected when measurements are taken from different parts of the sun’s disk. Specifi cally, measurements of the 656-nm line in hydrogen taken from opposite sides on the sun’s equator—one side approaching Earth and the other receding—differ from each other by 0.0090 nm. Use this information to fi nd the rotational period of the sun’s equator. Express your answer in days. (The sun’s equatorial radius is 6.96 x 108 m.)
(please type answer fast)
1. a) Using the virial mass for a spherical distribution of stars of radius R and mass M, find how R depends on o and Lassuming some constant M/L. b) Now, assume that all ellipticals have some constant surface brightness to show that L < 04
Don't provide hand writing solution
A galaxy G is moving away radially with speed with respect to an observer O. The relation between X, the wavelength of light emitted at G, and λo, the wavelength observed at O, is 入。 λ = λe λε 1+B 1- B' = where ẞ v/c (c is the speed of light). For ẞ < 1 find a power series expansion of the above formula up to and including terms of order ẞ³.
A star’s spectrum emits more radiation with a wavelength of 690.0 nm than with any other wavelength. If the star is 9.78 ly from Earth and its radius is 7.20 × 108 m, what will an Earth-based observer measure for this star’s intensity? Stars are nearly perfect blackbodies. (Note: ly stands for light-years.) Answer in W/m2
ans and get upvotes
What fraction of the light from the Sun is intercepted and reflected by the Earth? To get an upper bound let us assume the Earth is perfectly reflective, like it would be if it were covered in clouds. To compute it, compare the cross-section of the Earth (the area of a circle with radius REarth) to the area of a sphere centered on the Sun that has a radius equal to the radius of the orbit of the Earth (meaning, take the ratio of those two numbers). You can easily find sizes and distances on the Internet. Please express them in the same units to take a meaningful ratio (meter or kilometers will work best). SHOW YOUR WORK!
1.11 Calculate the Doppler width of a spectrum line from a neon discharge tube operating at a temperature of 100°C. The value of the Boltzmann constant k is 1.38 x 10-23 joules per degree Kelvin (J/K) and the mass of the neon atom is 3.34 x 10-26 kg. Take A = 600 nm and find the line width in both frequency and wavelength.
Does a cylinder surface have "intrinsic' curvature? i.e if you stay on the cylindrical surface and make geometric measurement, will there be devia- tions from euclidean geometry?
Assume that the radiation coming from Andromeda is all due to solar-like stars (MV, = 4.83). How many stars are there in the Andromeda galaxy according to this approximation?

SEE MORE QUESTIONS

Recommended textbooks for you

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

College Physics

Physics

ISBN:

9781938168000

Author:

Paul Peter Urone, Roger Hinrichs

Publisher:

OpenStax College

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

College Physics

Physics

ISBN:

9781938168000

Author:

Paul Peter Urone, Roger Hinrichs

Publisher:

OpenStax College

Astronomy

Physics

ISBN:

9781938168284

Author:

Andrew Fraknoi; David Morrison; Sidney C. Wolff

Publisher:

OpenStax

Modern Physics

Physics

ISBN:

9781111794378

Author:

Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Publisher:

Cengage Learning

SEE MORE TEXTBOOKS