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1. What Is Big History?

### 1.3 Scale

Shifting between different scales is a pillar of Big History and a useful skill. This infographic helps you to understand, practice, and compare measurement units that correspond to these scales.

A guide to scientific notation, calendar notation, and other common measures. Download the full-size version of this image. PDF.

### Counting in Time

A googol is 10^\text{100}, or a 1 followed by 100 zeros. This is actually not the biggest number in the world, though. The largest named number is a centillion, which is 10303, or a 1 followed by 303 zeros. It’s probably obvious to you that these are both really big numbers. Writing big numbers is a lot easier if you use scientific notation because it saves you from having to write all those zeros. But what about counting big numbers like these? There is no shortcut like scientific notation for actually counting big numbers. So how long would it actually take?

Imagine how long it would take to count to six different numbers by counting one number per second. How long would it take to count the following numbers in seconds, minutes, hours, or days? Try calculating the time it would take for you to count each of these numbers:

• 100

• 1,000

• 10,000

• 100,000

• 1,000,000

If you like, you can use the Ingredients of the Counting in Time worksheet and fill in your answers. When complete, take a look at the Counting in Time answer key to compare your results.