Footnote
c Consider how long it would take you just to count 100 billion stars. If you were able to count a new one each second—and keep at it 24 hours a day—it would take you 3,171 years!
c Consider how long it would take you just to count 100 billion stars. If you were able to count a new one each second—and keep at it 24 hours a day—it would take you 3,171 years!