FDSC 2000 Chapter : Chapter 8
Document Summary
Roughly 3 feet: 3700 meters can also be written as: 3. 7 x 10^3: one meter can also be written as: Astronomical unit : average distance between the sun and the earth. Light year : distance light travels in one year. 1 ly = 63,000 au or 6. 3 x 10^4 au. Km are appropriate for distances on or near earth. On the scale of the solar system, distances are described in terms of au. On galaxy scales, we use the light year (ly) or the parsec. Distances between galaxy groups are best measured in millions of ly (mly) Distances across the universe are usually measured in billions of ly (gly) According to the greeks: the heavens represent perfection the heavens are unchanging the circle is the perfect shape the almagest written by ptolemy is the only surviving ancient book on astronomy.
