21st Century Astronomy
6th Edition
ISBN: 9780393428063
Author: Kay
Publisher: NORTON
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 13, Problem 34QP
(a)
To determine
The amount of luminous than the sun is a star on the far right side of plot.
(b)
To determine
The amount of luminous than the sun is a star on the far left side of plot.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
"51 Pegasi" is the name of the first normal star (besides the Sun) around which a planet was discovered. It is in the constellation Pegasus the horse. Its parallax is measured to be 0.064 arcsec.
a. What is its distance from us?
b. The apparent brightness is 1.79 × 10-10 J/(s·m2 ). What is the luminosity? How does that compare with that of the Sun? Look up the temperature: how do
A star has a measured radial velocity of 300 km/s.
If you measure the wavelength of a particular
spectral line of Hydrogen as 657.18 nm, what was
the laboratory wavelength (in nm) of the line?
(Round your answer to at least one decimal place.)
nm
Which spectral line does this likely correspond to?
Balmer-alpha (656.3 nm)
Balmer-beta (486.1 nm)
Balmer-gamma (434.0 nm)
Balmer-del ta (410.2 nm)
As a star runs out of hydrogen to fuel nuclear fusion in its core, changes within the star usually cause it to leave the main sequence, expanding and cooling as it does so. Would a star with a radius 6 times that of the Sun, but a surface temperature 0.4 times that of the Sun, be more, or less luminous than the Sun?
Show and explain your reasoning.
You may assume the surface area of a sphere is A = 4πr2.
Chapter 13 Solutions
21st Century Astronomy
Ch. 13.1 - Prob. 13.1CYUCh. 13.2 - Prob. 13.2CYUCh. 13.3 - Prob. 13.3CYUCh. 13.4 - Prob. 13.4CYUCh. 13 - Prob. 1QPCh. 13 - Prob. 2QPCh. 13 - Prob. 3QPCh. 13 - Prob. 4QPCh. 13 - Prob. 5QPCh. 13 - Prob. 6QP
Ch. 13 - Prob. 7QPCh. 13 - Prob. 8QPCh. 13 - Prob. 9QPCh. 13 - Prob. 10QPCh. 13 - Prob. 11QPCh. 13 - Prob. 12QPCh. 13 - Prob. 13QPCh. 13 - Prob. 14QPCh. 13 - Prob. 15QPCh. 13 - Prob. 16QPCh. 13 - Prob. 17QPCh. 13 - Prob. 18QPCh. 13 - Prob. 19QPCh. 13 - Prob. 20QPCh. 13 - Prob. 21QPCh. 13 - Prob. 22QPCh. 13 - Prob. 23QPCh. 13 - Prob. 24QPCh. 13 - Prob. 25QPCh. 13 - Prob. 26QPCh. 13 - Prob. 27QPCh. 13 - Prob. 28QPCh. 13 - Prob. 29QPCh. 13 - Prob. 30QPCh. 13 - Prob. 31QPCh. 13 - Prob. 32QPCh. 13 - Prob. 33QPCh. 13 - Prob. 34QPCh. 13 - Prob. 35QPCh. 13 - Prob. 36QPCh. 13 - Prob. 37QPCh. 13 - Prob. 38QPCh. 13 - Prob. 39QPCh. 13 - Prob. 40QPCh. 13 - Prob. 41QPCh. 13 - Prob. 42QPCh. 13 - Prob. 43QPCh. 13 - Prob. 44QPCh. 13 - 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
- Star A and Star B are a bound binary at a distance of 20 pc from the Earth. Their separation is 30 AU. Star A has a mass twice that of Star B. The orbital period of the binary is 100 years. Assume the stars orbit in circular orbits. a. What is the parallax of Star A, in units of arcsec? Assume parallax is measured from the Earth. For part a, ignore the presence of the binary companion. b. What is the angular separation we would observe between Star A and Star B, in units of arcsec? If we compare multiple images of this star system taken across different months and years, which source of motion will be the dominant effect? What is the total mass of the binary system (combined mass of Star A and Star B)? Provide your answer in both kg and solar masses. c. d. What is the distance from Star A to the center of mass of the binary system?arrow_forwardA star has a measured radial velocity of 100 km/s. If you measure the wavelength of a particular spectral line of Hydrogen as 486.42 nm, what was the laboratory wavelength (in nm) of the line? (Round your answer to at least one decimal place.) Which spectral line does this likely correspond to? Balmer-alpha (656.3 nm) Balmer-beta (486.1 nm) Balmer-gamma (434.0 nm) Balmer-delta (410.2 nm)arrow_forwardThe spectral type of a star is directly related to its color. Recall that a star emits light as a blackbody, which has a particular shape to its spectrum, as shown in this figure. Based on this, what basic property of a star determines its color (and thus its spectral type)? Choose one: A. age B. composition C. radius D. temperaturearrow_forward
- . The spectrum of Star A peaks at 700 nm. The spectrum of Star B peaks at 470 nm. We know nothing about what stage of stellar evolution either of these stars are in. Which of the following are true? A. Star A has a higher luminosity than Star B. B. Star B has a higher luminosity than Star A. C. Star A is cooler than Star B. D. Not enough information to comment on their luminosities. E. B and C F. C and Darrow_forward= A star population is composed of stars with masses in the range between 1M and 150M. The initial mass function is = 0 (M/M)-2.3, where o (Mo). The luminosity of a star = (M/M) 3.3. Calculate the percentage of the total luminosity of the stars in the population which is produced by stars with mass between 120M and 150M. scales with its mass as L/Larrow_forwardSuppose a star has a luminosity of 7.0x1026 watts and an apparent brightness of 4.0x10-12 watt/m?. How far away is it? Give your answer in both kilometers and light-years.arrow_forward
- Using solar units, we find that a star has 4 times the luminosity of the Sun, a mass 1.25 times the mass of the Sun, and a surface temperature of 4090 K (take the Sun's surface temperature to be 5784 K for the sake of this problem). This means the star has a radius of.................... solar radii and is a .................... star (use the classification).arrow_forward. A star"s position in the sky against distant background objects has shifted by 0.4" in 6 months it returned where it was. what is the stellar parallax p of this star? Ans. p=0.2" b. How far is this star from the Sun?arrow_forwardQUESTION 10 Which of the following Cepheid variable stars would appear to be the brightest from Earth? A Cepheid variable star that is 10,000 times as luminous as the sun. A Cepheid variable star with a period of 10 days. A Cepheid variable star with a period of 3 days. There is not enough information given.arrow_forward
- Which of the following is least reasonable regarding a star's position on the HR diagram? Group of answer choices Red dwarfs are small and cool and inhabit the lower right part of the HR diagram. Our Sun is pretty average and is located somewhere around the center of the diagram. Blue giants are hot and big and are located in the upper left part of the HR diagram. White dwarfs are small and cool and are located in the lower left part of the HR diagram. Red giants are big and cool and are located in the upper right part of the HR diagram.arrow_forwardThe period–luminosity relation is useful in determining a. the mass of a star for which the distance is known. b. the temperature of a star for which we know the luminosity. c. the radius of the bulge of our galaxy. d. the distance to globular clusters that contain Cepheid variables. e. the mass of the Milky Way Galaxy.arrow_forwardChoose the statements that correctly describe the characteristics of the stars located in the labeled quadrants of the H-R diagram. Luminosityarrow_forwardarrow_back_iosSEE MORE QUESTIONSarrow_forward_ios
