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2 Announcements: Get clickers registered! Homework #2 due Tuesday Reading: Chp 1: sections 1.2 and 1.3
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 3 Naked-Eye Astronomy Celestial Sphere Diurnal Motion
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 4 Stonehenge: 5100 years old A Mayan building faces sunset Astronomical Alignments in Egyptian Tombs
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 5 Vocabulary: longitude/latitude celestial sphere celestial pole/equator horizon/zenith constellation ecliptic/zodiac
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 6 Rotational axis
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 7 Latitude: angle measured in north/south direction zero degrees at equator +90 degrees at north pole -90 degrees at south pole Longitude: angle measured in east/west direction zero degrees at Greenwich, England measured to 180 degrees east and west
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9 The Celestial sphere Figure 1.2 x zenith
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 10 Horizon: defined by plane perpendicular to your body Zenith: the point directly above your head. changes with time!!
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 11 Celestial Pole: North and South pole projected onto celestial sphere. Celestial Equator: Earth’s equator projected onto celestial sphere.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 12 Constellation: Orion
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 13 Orion
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 16 Constellations: The stars that comprise a constellation are not actually physically associated in space. Each is at a different distance from the Earth. If you could travel to a different star, you would not see the same patterns in the sky!!
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 17 Observing Astronomical Phenomena Daily: Monthly: Yearly: Other: Objects rise in the East and set in the West. Different constellations visible at different times of year. Moon seen at different “phases”.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 18 Day and Night: The Spinning Earth Virtual planetarium…
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 19 If you could hover over the Earth’s north rotational pole and look down at the Earth as it spins, you would see that the Earth spins in a ____________ direction. a) clockwise b) counter-clockwise
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 20 The Rising and Setting Stars Figure 1.4 Virtual planetarium…
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 21 Rising and Setting Stars: Stars only rise perpendicular to the horizon if you happen to be living on the equator In the Northern hemisphere, stars rise inclined toward the south (to the north if you are in the southern hemisphere). At the poles, stars will not rise or set, but circle around you!!
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 22 Constellations change with seasons Figure 1.5