1. Making Sense of the Universe
A Sense of Scale
Making Sense of the Universe

2. Some Numbers To Consider
Diameter of the earth: 12,800 km
Diameter of the moon: 3500 km
Earth-Moon Distance: 384,000 km

3. Some Numbers To Consider
Diameter of the earth: 12,800 km
Diameter of the sun: 1,400,000 km
Earth-Sun Distance: 150,000,000 km

5. Astronomical Unit The average distance from the earth to the sun
Approximately 93,000,000 miles

6. The Light Year The distance light travels in one year
9.46 x 1012 km (9,460,000,000,000 km)
Closest star (Non-sun) is α Centauri: 41,600,000,000,000 km; 4.4 light years

8. ←----------------100,000 light years------------→

9. ←--------- 4 million light years ----------→

11. Questions from book:
Page 15: Questions For Review: #2-6