1	Chapter 1 Our Place in the Universe Chapter Outline A Modern View of the Universe The Scale of the Universe Spaceship Earth The Human Adventure of Astronomy
2	Quantitative Nature of Science Read Appendix C Science is quantitative Ordinary language unable to portray precision or scale in scientific discourse Numbers essential to discussion and understanding Units of measurement essential to discussion and understanding Scientific notation Expressing number as product of two numbers; one lying between 0 and 9 multiplied by a power of ten Example: 86,400 = 8.64 x 10,000 = 8.64 x 10⁴
3	Our Place in the Universe
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5	Expanding Universe as an Expanding Raisin Cake
6	Parallax Parallax - apparent shift in position of foreground object relative to background objects due to motion of observer Nearby stars show parallactic shift Even nearby stars are so far away that parallactic shift is extremely small
7	Astronomical Distances Astronomical Unit (AU) - mean distance between Earth and Sun Light year (ly) - distance light travels in a vacuum in one year Parsec (pc) - distance at which two objects separated by one AU subtend an angle of one second of arc
8	Lookback Time Refers to the amount of time since the light we see from a distant object, such as a cluster of galaxies, was emitted. Example: if a galaxy is 400 million light years distant, then light has been in transit for 400 million years, or we see the object as it existed 400 million years ago and not as it exists now.
9	Universe is a Universe of Galaxies
10	Our Galaxy’s Structure
11	Motion in Our Galaxy
12	Solar System Model Scale 1-to-10 billion
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14	A Rotating/Precessing Earth
15	Earth’s Orbit
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17	The Big Picture This chapter develops a broad overview of the universe. The details are the content of later chapters. Earth is not the center of the universe, but orbits a modest star in a modest galaxy. Life cycle of stars is the source of the chemical evolution of the universe. Various scale sizes in the universe cover an immense range from the fundamental particle scale to the large scale structure in the universe. Evidence suggests that the age of the Solar System, 4.6 billion years, is about 1/3 the age of the universe, about 14 billion years. To understand the universe, we must know something about the four topics: motion, matter and light interaction, space, and time.