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Astronomy 101 Section 020 Lecture 3 A Dynamic Example: Motions of the Earth and Moon John T. McGraw, Professor Laurel Ladwig, Planetarium Manager
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Day, Night and the Motion of the Stars - The Diurnal (Daily) Motion n Half of the Earth (and Moon and every other planetary body) is always illuminated by the sun. n Rotation causes the apparent diurnal changes in the sky.
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Why the Constellations Change During the Year n Revolution of the Earth about the sun causes the annual changes in the sky.
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The Reasons for Seasons n The Earth’s rotation axis is tilted 23.5° to the ecliptic. n The ecliptic is the plane of the Earth’s orbit about the sun.
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Solar Energy: Designing Your House
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The Ecliptic, Equinoxes and Solstices n The ecliptic (green) is the plane of the Earth’s orbit around the sun.
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That Winter/Summer Thing Again n Some snappy circles!
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Time Zones Aid the Human (Rat?) Race! n Time zones are the result of the Earth’s rotation. n When it is noon in Des Moines, what time is it in LA? In Miami?
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The Motions of the Moon: Lunar Phases and Synchronous Rotation n The moon’s phases result from its revolution about the Earth. n Synchronous rotation means that one side of the moon always faces the Earth. The moon rotates once per revolution.
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Orbit and Phases of the Moon
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Phases and Shadows: A Demonstration
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The Moon’s Synchronous Rotation: A Demonstration
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The “Coming Together” and “Starry” Months: Synodic and Sidereal Periods
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The 5° Inclination of the Moon’s Orbit Relative to the Ecliptic
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How Eclipses Can Occur
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Three Types of Lunar Eclipses
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A Total Lunar Eclipse
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The Geometry of a Total Solar Eclipse
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Solar Eclipses n Total (1991, La Paz) and annular (1973, Costa Rica) solar eclipses.
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Eclipse Paths for Total Solar Eclipses: 1997 - 2020
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