21^st Century Astronomy, Second Edition

Chapter 2: Patterns in the Sky—Motions of Earth

Study Plan

In this chapter we begin our journey in earnest, starting out as our ancestors did when they first gazed at the Sun, Moon, and stars, and tried to understand what they saw. With the benefit of knowledge hard-won over the centuries, we will look at patterns present both in the sky and on Earth, and then look beyond appearances to the underlying motions that cause those patterns. Here we will discover

• How the stars appear to move through the sky as Earth rotates on its axis, and how those motions differ when seen from different latitudes on Earth.
• The fundamental concept of a frame of reference, and how Earth's rotating frame of reference affects weather patterns and other terrestrial phenomena.
• How Earth's motion around the Sun and the tilt of Earth's axis relative to the plane of its orbit combine to determine which stars we see at night and the seasons we feel through the year.
• The motion of the Moon in its orbit about Earth, and how that motion, together with the motion of Earth and the Moon around the Sun, shapes the phases of the Moon and the spectacle of eclipses.

Organize

1. Read Chapter 2 in your textbook or ebook.
2. Take the Diagnostic Quiz to assess your understanding of the basic concepts and identify gaps in your understanding of the assigned reading.

Learn

1. Access the Animations given for this chapter. These brief lessons enhance your understanding of core concepts.
   The Celestial Sphere and the Ecliptic
   Section: 2.2
   The Earth Spins and Revolves
   Section: 2.2 and 2.3
   The Moon's Orbit: Eclipses and Phases
   Section: 2.4 and 2. 5
2. Use the FlashCards to test your memory for new terms.
3. Review Foundations Box 2.1 on Relative Motions and False Forces, and the three Excursions Boxes for this chapter:
• 2.1 Where Are the Constellations?
• 2.2 Why Is It Surprising That a.d. 2000 Was a Leap Year?
• 2.3 The Dark Side of the Moon
4. Work the "Thinking about the Concepts" and "Applying the Concepts" questions in the end of chapter review materials.
5. If your instructor has assigned SmartWork online homework, login from the right navigation pane for additional practice and review.

Connect

1. Periodic Connections boxes and the Seeing the Forest through the Trees section at the chapter's end draw your attention to recurring themes and help prepare you for concepts explored more fully in subsequent chapters.
2. Visit Astronomy in the News for breaking news of new discoveries and the opportunity to apply what you've learned in this chapter to real-world (and real Universe) events.

Instructors now have an easy way to collect students’ online quizzes with the Norton Gradebook without flooding their inboxes with e-mails.

Students can track their online quiz scores by setting up their own Student Gradebook.