Scales in our World

1. Scales in our World 1 mm  pencil 10-3 m 1 cm  width of your finger 10-2 m 10 cm  width of your hand 10-1 m 1 m  a long step 100 m 10 m  width of the classroom 101 m 100 m  length of a football field 102 m 1000 m = 1 km  size of our campus 103 m 10 km  size of a small city 104 m 100 km  typical distance between cities 105 m 1,000 km  width of Turkey 106 m 10,000 km  diameter of the Earth 107 m 100,000 km  ¼ distance to the Moon 108 m

2. Scales in the Universe • Two new units must be defined: • AU: Astronomical Units  Distance Earth - Sun = 150,000,000 km • Lightyear  The distance light travels in one year = 65,700 AU = 9,5 1015 m • 1 AU  distance to the Sun ~1011 m • 10 AU  Sun – Saturn distance ~1012 m • 50 AU  Sun – Pluto distance 7.5x1012 m • 50,000 AU = 0.8 ly  Sun’s sphere of influence 7.5x1015 m • 3 ly  Nearest stars 28.5x1015 m • 100,000 ly  size of our galaxy 1021 m • 2,000,000 ly  distance to the nearest galaxy 2x1022 m • 50,000,000 ly  size of our local cluster 5x1023 m • 10,000,000,000 ly  size of the known universe 1026 m