Early Astronomy

Early Astronomy

Ancient Greeks

• The "Golden Age" of early Astronomy was center in Greece (600 B.C - A.D 150)

• Greeks used philosophical arguments to explain the natural world and observations

Ancient Greeks

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  They used trigonometry and geometry to measure the sizes and distances of the sun and the moon.

Aristotle (Greek philosopher)

• said the world was round because it always casts a curved shadow on the moon when it pases between the moon and the sun.

Eratoshenes

• discovered the circumference of the planet was about 39, 300 kilometers

• know we know that it is actually 40, 075 kilometers

Multiple Choice

What did Eratosthenes discovered?

• the earth's circumference

• that the earth is round

• the earth's distance from the sun.

Hipparchus

• he catalog all the stars

• determined the location of almost 850 stars

• he divided stars into 6 groups according to their brightness.

• he determined how long was a year

Open Ended

What did Hipparchus discovered?