21st Century Astronomy Seventh Edition (7th), (2022)
By Stacy Palen & George Blumenthal
All Chapters 1-24| Latest Version With Well Detailed Answers| Rated A+
,Chapter 1: Thinking Like An Astronomer __________________________________________ 3
Chapter 2: Patterns In The Sky—Motions Of Earth And The Moon _____________________ 42
Chapter 3: Motion Of Astronomical Bodies _______________________________________ 74
Chapter 4: Gravity __________________________________________________________ 105
Chapter 5: Light ____________________________________________________________ 137
Chapter 6: The Tools Of The Astronomer ________________________________________ 168
Chapter 7: The Formation of Planetary Systems __________________________________ 201
Chapter 8: The Terrestrial Planets and Earth’s Moon_______________________________ 232
Chapter 9: Atmospheres of the Terrestrial Planets ________________________________ 268
Chapter 10: Worlds of Gas and Liquid—The Giant Planets __________________________ 301
Chapter 11: Planetary Moons and Rings _________________________________________ 334
Chapter 12: Dwarf Planets and Small Solar System Bodies __________________________ 366
Chapter 13: Taking the Measure of Stars ________________________________________ 396
Chapter 14: Our Star — The Sun _______________________________________________ 426
Chapter 15: The Interstellar Medium and Star Formation ___________________________ 456
Chapter 16: Evolution of Low-Mass Stars ________________________________________ 486
Chapter 17: Evolution of High-Mass Stars ________________________________________ 518
Chapter 18: Relativity and Black Holes __________________________________________ 550
Chapter 19: Galaxies ________________________________________________________ 584
Chapter 20: The Milky Way—A Normal Spiral Galaxy ______________________________ 617
Chapter 21: The Expanding Universe ___________________________________________ 650
Chapter 22: Cosmology ______________________________________________________ 681
Chapter 23: Large-Scale Structure In The Universe ________________________________ 714
Chapter 24: Life ____________________________________________________________ 739
,CHAPTER 1: THINKING LIKE AN ASTRONOMER
Stacy Palen: 21st Century Astronomy Seventh Edition (7th Edition), (2022)
CONCEPT MAP
Sec 1.1
1. Astronomy
I. Definition
i. Astronomy Loosely Translated Means “Patterns Among The Stars” (MC: 1)
II. Your Place In The Universe
i. Your Address: Street, City, Town, Country, Earth, Sun, Milky Way, Local Group,
Virgo Supercluster, Universe (MC: 3, SA: 1)
ii. Solar System: Classical Versus Dwarf Planets (TF: 1, 2, MC: 1–4, 7, SA: 2)
iii. Milky Way: Contains 200 To 400 Billion Stars (MC: 3, 5–7)
iv. Local Group (MC: 3, 8)
v. Virgo Supercluster (TF: 3, MC: 3)
vi. Universe: Contains Hundreds Of Billions Of Galaxies, Roughly As Many Stars
As In The Milky Way (TF: 4)
vii. Much Of The Universe Is Made Of Dark Matter, And All Of Space Is Permeated
By Dark Energy (TF: 5, MC: 9, 10)
III. Scale Of The Universe
i. Speed Of Light, C 3 108 M/S (MC: 11)
ii. D V T (TF: 2, MC: 12–17)
iii. Light Year Is A Measure Of Distance (TF: 6, MC: 12, SA: 3)
iv. Distance Versus Time Comparison: Circumference Of The Earth Versus
Snapping Your Fingers (MC: 19, 20, SA: 4–6)
,IV. Origin And Evolution Of Universe
i. Age Of Universe: 13.7 Billion Years (MC: 21)
ii. Big Bang Created The Initial Chemical Elements: H, He, Li, Be, B (TF: 7, MC:
22, 23)
iii. Stars Manufactured The Other Chemical Elements From Nuclear Burning And
Explosions (TF: 7, 8, MC: 24, 25, SA: 7)
iv. Solar System Formed
v. Life Evolved On Earth
Sec 1.2
2. Science Involves Exploration And Discovery
I. Evolution Of Astronomy From New Technology
i. Satellites, E.G., Sputnik, Lunar Exploration, Solar System Exploration (TF: 10,
MC: 26, SA: 8, 9)
ii. Space-Based Astronomy Used For High Spatial Resolution And Access To
Wavelengths Blocked By The Atmosphere (TF: 10, MC: 27, SA: 9, 10)
iii. Cross Disciplines: Astronomy, Physics, Chemistry, Geology, Planetary Science
iv. Computers: A New Important Tool For Astronomers (SA: 9)
Sec 1.3
3. Science Is A Way Of Viewing The World
I. Scientific Method
i. Scientific Method (MC: 28, 29, SA: 11)
ii. Rational Inquiry
iii. Facts
iv. Hypothesis (MC: 28, 30, SA: 11)
v. Theory (MC: 28, 30, SA: 12)
vi. Testable Predictions/Falsifiable (TF: 10, 11, MC: 28, SA: 11)
vii. Physical Laws
,viii. Scientific Principle
ix. Occam’s Razor (MC: 31, 32)
x. Cosmological Principle (TF: 12, MC: 33, 34, SA: 13, 14)
II. Scientific Knowledge Changes And Evolves
i. Scientific Knowledge Continually Evolves, Usually Slowly And Gradually,
Because Of New Information (MC: 28)
ii. Even When A Theory Is Accepted As True, It May Need Revision Later When
New Data Comes Along (TF:14, MC: 28, 35, SA; 12)
iii. Scientific Revolutions: E.G. Newton/Gravity, Einstein/Special And General
Relativity, And Quantum Me- Chanics (MC: 36, SA: 15)
iv. “Modern Physics,” Post-Quantum Mechanics
III. Challenges To Science
i. Cultural/Philosophical/Religious Influences
ii. Scientific Facts And Theories Need To Be Judged Based On Their Predictions
And Observations Alone
iii. Scientists Never Ignore Data Just Because It Doesn’t Fit Their Theory
Sec 1.4
4. Patterns Make Our Lives And Science Possible
I. Patterns Point Out Underlying Scientific Principles
I. Patterns Point Out Underlying Scientific Principles (TF: 15, MC: 37, SA: 16, 17)
Ii. Examples Of Patterns: Rise/Setting Of Sun, Seasons (MC: 38, SA: 16, 17)
II. Mathematical Tools
I. Mathematics Is The “Language Of Science,” A Tool To Quantify And Compare
Patterns (MC: 39, SA: 18)
Ii. Scientific Notation (MC: 40–43)
Iii. Ratios And Proportionalities (MC: 44–49)
Iv. Units (MC: 50, 51)
, v. Reading A Graph (MC: 52)
vi. Slope Of A Line (MC: 53)
Sec 1.5
5. Thinking Like An Astronomer
I. What Is A Planet?
i. Pluto Was Reclassified As A Dwarf Planet In 2006 (TF: 2, MC: 54–56, SA: 19)
Sec 1.6
6. Origins: An Introduction
I. Astrobiology
i. Astrobiology: Study Of Whether There Is Life Elsewhere In The Solar System
And The Universe (MC: 57, SA: 20)
TRUE/FALSE QUESTIONS QUESTIONS
1. Our Sun Is One Of The Most Massive And Luminous Stars In The Milky Way.
ANS: FALSE
The Sun Is Actually A Relatively Average Star In Terms Of Mass And Luminosity
Compared To Others In The Milky Way.
DIF: Easy REF: Section 1.1 MSC: Factual TOP: 1iiii
2. Pluto Is The Only Dwarf Planet In Our Solar System.
ANS: FALSE
Pluto Is One Of Several Dwarf Planets In Our Solar System, Including Eris, Haumea,
And Makemake
,DIF: Easy REF: Section 1.1 MSC: Factual TOP: 1iiii | 5Ii
3. The Local Group Is A Member Of The Virgo Supercluster.
ANS: TRUE
The Local Group, Which Includes The Milky Way, Is Indeed Part Of The Virgo
Supercluster.
DIF: Medium REF: Section 1.1 MSC: Factual TOP: 1iiiv | 1iiv
4. There Are Nearly 1,000 Times More Galaxies In The Observable Universe As There
Are Stars In The Milky Way.
ANS: FRUE
There Are Many More Galaxies In The Observable Universe, But The Number Isn't
1,000 Times Greater Than The Stars In The Milky Way. The Number Is Vastly Larger.
DIF: Medium REF: Section 1.1 MSC: Factual TOP: 1iivi
5. A Great Majority Of The Matter In Our Universe Is Not Visible.
ANS: TRUE
This Refers To Dark Matter, Which Makes Up A Significant Portion Of The Universe's
Mass But Cannot Be Seen Directly.
DIF: Easy REF: Section 1.1 MSC: Factual TOP: 1iivii
6. A Light-Year Is A Unit Commonly Used In Astronomy As A Measure Of Time.
ANS: FALSE
A Light-Year Is A Measure Of Distance, Not Time. It Is The Distance Light Travels In
One Year.
DIF: Easy REF: Section 1.1 MSC: Factual TOP: 1iiiiii
,7. Human Beings Are Composed Almost Entirely Of Elements That Were Created In The
Big Bang.
ANS: FALSE
While The Lighter Elements (Like Hydrogen And Helium) Were Formed In The Big
Bang, Heavier Elements Were Created Later Through Stellar Processes.
DIF: Medium REF: Section 1.1 MSC: Applied TOP: 1ivii | 1iviii
8. The Heavy Elements That Make Up Most Of Earth Were Formed Via Nuclear Fusion
In The Center Of The Sun.
ANS: FALSE
Heavier Elements Were Formed In Supernovae, Not Just Within The Sun.
DIF: Easy REF: Section 1.1 MSC: Factual TOP: 1iviii
9. The Invention Of Satellites Advanced Astronomy Because Telescopes On Satellites
Can Observe Wavelengths Of Electromagnetic Radiation, Such As X-Rays, That Cannot
Penetrate The Earth’s Atmosphere.
ANS: TRUE
Satellites Enable The Observation Of Wavelengths That Atmospheric Conditions Would
Block, Significantly Advancing Our Understanding Of The Universe.
DIF: Easy REF: Section 1.2 MSC: Factual TOP: 2Iii | 2Iiii
10. If A Scientific Theory Cannot Be Tested, It Is Assumed To Be True.
ANS: FALSE
A Theory Must Be Testable To Be Considered Scientific. If It Cannot Be Tested, It
Cannot Be Proven True Or False.
DIF: Easy REF: Section 1.3 MSC: Conceptual TOP: 3Ivi
,11. A Crucial Component Of A Scientific Theory Is That It Is Able To Be Tested By
Observations And Thus Proven True Or False.
ANS: TRUE
This Is A Fundamental Requirement For A Scientific Theory—Its Predictions Must Be
Testable And Falsifiable.
DIF: Easy REF: Section 1.3 MSC: Conceptual TOP: 3Ivi
12. The Copernican Principle States That There Is Nothing Special About Our Local
Region Of The Universe.
ANS: TRUE
The Copernican Principle Asserts That Earth And Our Solar System Are Not At The
Center Of The Universe.
DIF: Easy REF: Section 1.3 MSC: Conceptual TOP: 3Ix
13. One Consequence Of The Principle Of Universality Is That Gravity Works The Same
Here On Earth As It Does On The Planet Jupiter.
ANS: TRUE
Gravity Is Universal, Meaning That The Fundamental Laws Of Physics Apply
Everywhere, Regardless Of Location, Including On Earth And Jupiter.
DIF: Medium REF: Section 1.3 MSC: Conceptual TOP: 3Ix
14. Once A Scientific Theory Is Declared To Be True, It Is Believed From That Time
Onward.
ANS: FALSE
Scientific Theories Are Always Subject To Revision Based On New Evidence. They Are
Never Considered Absolutely Permanent.
DIF: Medium REF: Section 1.3 MSC: Conceptual TOP: 3iiii
, 15. Science Proceeds By Presuming That Observed Patterns In Nature Can Be Attributed
To An Underlying Physical Explanation.
ANS: TRUE
Science Relies On The Idea That The Natural World Operates According To Consistent
Rules That We Can Discover Through Observation And Experimentation.
DIF: Easy REF: Section 1.4 MSC: Factual TOP: 4Ii
MULTIPLE CHOICE QUESTIONS
1. The Word Astronomy Means:
A. “Patterns Among The Stars”
B. “To Study The Stars”
C. “Discovering The Universe”
D. “The Movement Of The Stars”
E. “Personality Traits Set By The Stars”
ANS: A.
Astronomy Comes From The Greek Word "Astron" Meaning "Star" And "Nomos"
Meaning "Law." It Refers To The Study Of Celestial Objects And Phenomena Beyond
Earth, Specifically Focusing On The Patterns Of Stars And Other Cosmic Entities.
DIF: Easy REF: Section 1.1 MSC: Factual TOP: 1Ii
2. According To The Figure Below, If You Were To Specify Your Address In The
Universe, Listing Your Membership From The Smallest To Largest Physical Structures,
It Would Be:
A. Earth, Local Group, Solar System, Andromeda, The Universe
B. Earth, Solar System, Local Group, Milky Way, The Universe