Loose Leaf For Explorations: Introduction To Astronomy
9th Edition
ISBN: 9781260432145
Author: Thomas T Arny, Stephen E Schneider Professor
Publisher: McGraw-Hill Education
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Question
Chapter 17, Problem 1TQ
To determine
The evidences based on the amount of interstellar matter and kind of stars in E and S galaxies which indicates that Hubble’s tuning fork diagram may not represent the evolutionary change between these two galaxies
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Why is it that there doesn't seem to be an equivalent to the H-R diagram of stars for galaxies?
A Type la supernova explodes in a galaxy at a
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Chapter 17 Solutions
Loose Leaf For Explorations: Introduction To Astronomy
Ch. 17 - Prob. 1QFRCh. 17 - Prob. 2QFRCh. 17 - Prob. 3QFRCh. 17 - Prob. 4QFRCh. 17 - (17.3) Why are galaxy collisions of interest?Ch. 17 - Prob. 6QFRCh. 17 - Prob. 7QFRCh. 17 - Prob. 8QFRCh. 17 - Prob. 9QFRCh. 17 - Prob. 10QFR
Ch. 17 - Prob. 11QFRCh. 17 - Prob. 12QFRCh. 17 - Prob. 13QFRCh. 17 - Prob. 14QFRCh. 17 - Prob. 15QFRCh. 17 - Prob. 16QFRCh. 17 - Prob. 17QFRCh. 17 - Prob. 18QFRCh. 17 - Prob. 19QFRCh. 17 - Prob. 20QFRCh. 17 - Prob. 21QFRCh. 17 - Prob. 22QFRCh. 17 - Prob. 1TQCh. 17 - Prob. 2TQCh. 17 - Prob. 3TQCh. 17 - Prob. 4TQCh. 17 - Prob. 5TQCh. 17 - Prob. 6TQCh. 17 - Prob. 1PCh. 17 - Prob. 2PCh. 17 - Prob. 3PCh. 17 - Prob. 4PCh. 17 - Prob. 5PCh. 17 - Prob. 6PCh. 17 - Prob. 7PCh. 17 - Prob. 8PCh. 17 - Prob. 9PCh. 17 - Prob. 10PCh. 17 - Prob. 1TYCh. 17 - Prob. 2TYCh. 17 - Prob. 3TYCh. 17 - Prob. 4TYCh. 17 - Prob. 5TYCh. 17 - Prob. 6TYCh. 17 - Prob. 7TYCh. 17 - Prob. 8TYCh. 17 - Prob. 9TYCh. 17 - Prob. 10TY
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- If the diameter of the Milky Way Galaxys visible disk, 80,000 ly, is represented in a model by a dinner plate with a diameter of 10 inches, what is the model distance to galaxy M31, 2.6 millionly away? What is the model distance to the Virgo galaxy cluster, 16 Mpc away? (Convert answers to feet.)arrow_forwardWhat evidence can you give that we live in a galaxy?arrow_forwardAccording to Hubble’s law, what is the recessional velocity of a galaxy that is 108 light-years away from us? (Assume a Hubble constant of 22 km/s per million light-years.)arrow_forward
- If we now realize dwarf ellipticals are the most common type of galaxy, why did they escape our notice for so long?arrow_forwardWe have said that the Galaxy rotates differentially; that is, stars in the inner parts complete a full 360° orbit around the center of the Galaxy more rapidly than stars farther out. Use Kepler’s third law and the mass we derived in Exercise 25.19 to calculate the period of a star that is only 5000 light-years from the center. Now do the same calculation for a globular cluster at a distance of 50,000 light-years. Suppose the Sun, this star, and the globular cluster all fall on a straight line through the center of the Galaxy. Where will they be relative to each other after the Sun completes one full journey around the center of the Galaxy? (Assume that all the mass in the Galaxy is concentrated at its center.)arrow_forwardA galaxy at a distance of 25 Mpc has a recession velocity of 1875 km/sec. What is Hubble’s constant based on this one galaxy? Why is this not a good way to determine Hubble’s constant? Galaxy NGC 123 has a velocity away from us of 1,320 km/s and the Hubble Constant's value is 70 km/s/Mpc. How far away is the galaxy according to Hubble's Law?arrow_forward
- If a galaxy has a radial velocity of 21,641 km/s, what is its expected distance from the Hubble Law? Assume that the Hubble Constant is 71 km/s/Mpc. Answer in Mpcarrow_forwardIn the reading, you were told that there were roughly 10,000 galaxies in the image of the Hubble Ultra Deep Field alone. The image is roughly 10 square arcminutes and there are roughly 1.5*10^8 square arcminutes composing the entire sky. With that in mind and assuming that the Hubble Ultra Deep Field represents an average part of the sky, roughly how many galaxies may exist in the observable universe? (Please include commas for every factor of 1,000; for example 2,343,567,890)arrow_forwardAssume that the number density of stars in the Milky Way is 0.14 pc-3. (e) There are 10" stars uniformly distributed across the galaxy. Also assume that there is one supernova every 30 years and all of them have same luminosity. Find the probablity, P, of a supernova causing extinction on Earth in total life span of the Sun.arrow_forward
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