Essential Cosmic Perspective
9th Edition
ISBN: 9780135795033
Author: Bennett
Publisher: PEARSON
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Question
Chapter 1, Problem 49EAP
To determine
To Explain: The way the total number of stars in the observable universe would be affected if 1 trillion small galaxies are considered instead of 100 billion large galaxies.
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power
1. A distant galaxy has an apparent magnitude of 10 and is 4,000 kpc away. What is its absolute magnitude? (Round your answer to at least one decimal place.)
The difference in absolute magnitude between two objects viewed from the same distance is related to their fluxes by the flux-magnitude relation.
FA/FB= 2.51(MB − MA)
2. How does the absolute magnitude of this galaxy compare to the Milky Way
(M = −21)?
Try Now
...
....
Listed below are some distances from Earth to other objects in the Milky Way galaxy. Convert each
distance to light-years. (Each of these distances is less than one light-year. For an added challenge,
convert each distance to light minutes or light seconds.)
1.
The distance from Earth to the Moon is about 384,400 km. How many light-years is this?
2.
The distance from Earth to Mars is about 784,000,000 km. How many light-years is this?
3.
The distance from Earth to Pluto is about 5,750,000,000 km. How many light-years is this?
Chapter 1 Solutions
Essential Cosmic Perspective
Ch. 1 - Prob. 1VSCCh. 1 - Prob. 2VSCCh. 1 - About how far away from Earth would the Sun be...Ch. 1 - Prob. 4VSCCh. 1 - Prob. 1EAPCh. 1 - Define astronomical unit and light-year.Ch. 1 - Explain the statement The farther away we look in...Ch. 1 - Prob. 4EAPCh. 1 - Prob. 5EAPCh. 1 - What do we mean when we say that the universe is...
Ch. 1 - In what sense are we “star stuff”?Ch. 1 - Use the cosmic calendar to describe how the human...Ch. 1 - Briefly explain Earth’s daily rotation and annual...Ch. 1 - Prob. 10EAPCh. 1 - Prob. 11EAPCh. 1 - Prob. 12EAPCh. 1 - Prob. 13EAPCh. 1 - Prob. 14EAPCh. 1 - Decide whether the statement makes sense (or is...Ch. 1 - Prob. 16EAPCh. 1 - Prob. 17EAPCh. 1 - Prob. 18EAPCh. 1 - Decide whether the statement makes sense (or is...Ch. 1 - Prob. 20EAPCh. 1 - Decide whether the statement makes sense (or is...Ch. 1 - Prob. 22EAPCh. 1 - Prob. 23EAPCh. 1 - An astronomical unit is (a) any planet’s average...Ch. 1 - The star Betelgeuse s about 600 light-years away....Ch. 1 - Prob. 26EAPCh. 1 - Prob. 27EAPCh. 1 - Prob. 28EAPCh. 1 - Prob. 29EAPCh. 1 - Prob. 30EAPCh. 1 - Prob. 31EAPCh. 1 - Prob. 32EAPCh. 1 - Prob. 34EAPCh. 1 - Thinking About Scale. One key to success m science...Ch. 1 - Prob. 36EAPCh. 1 - A Human Adventure. Astronomical discoveries...Ch. 1 - Prob. 38EAPCh. 1 - Group Activity: Counting the Milky Way’s Stars....Ch. 1 - Prob. 40EAPCh. 1 - Prob. 41EAPCh. 1 - Prob. 42EAPCh. 1 - Prob. 43EAPCh. 1 - Prob. 44EAPCh. 1 - Moonlight and Sunlight. How long does it take...Ch. 1 - Prob. 46EAPCh. 1 - Driving Trips. Imagine that you could drive your...Ch. 1 - Prob. 48EAPCh. 1 - Prob. 49EAPCh. 1 - Age of the Universe. Suppose we did not yet know...
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- The Tully-Fischer method relies on being able to relate the mass of a galaxy to its rotation velocity. Stars in the outer-most regions of the Milky Way galaxy, located at a distance of 50 kpc from the galactic centre, are observed to orbit at a speed vrot determine the mass in the Milky Way that lies interior to 50 kpc. Express your answer in units of the Solar mass. 250 km s-1. Using Kepler's 3rd Law,arrow_forwardA given star orbits the center of its galaxy at an average speed of v_star, at a distance of r_star from the center. The galaxy has 2 spiral arms, and the arms themselves orbit slower than the star -- at the same radius, they orbit at a speed of v_arm (in the same direction as the star). The galaxy's age is t_gal. In the history of this galaxy, how many times did this star cross through a spiral arm? Values: v_star = 200 km/s, r_star = 9 kpc, v_arms = 46 km/s, t_gal = 4 Gyrarrow_forwardOur galaxy is approximately 100,000 light years in diameter and 2,000 light years thick through the plane of the galaxy. If we were to compare the ratio of the diameter galaxy and its thickness to the ratio of the diameter of a CD and its thickness (CD has a diameter of 12 cm and thickness of 0.6 mm), what would be the factor differentiating those ratios? Put differently, if the galaxy were scaled down to the diameter of a CD, how many times thicker or thinner would the galaxy be than the CD? (For example if it would be twice as thick, you would answer 2 and if it were twice as thin you would answer 0.5 (aka 1/2))arrow_forward
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