How was Christopher Columbus inacurrate?

Answer 1

Christopher Columbus was inaccurate in four ways.

1. He believed that Japan was farther east then China.

2. He knew that the degree of longitude along the Equator) spanned 56⅔ miles, but did not know that this was in Arabic miles (about 1,830 m) rather than the shorter Roman miles which he used (1,480 m). He therefore thought the circumference of the Earth to be about 30,200 km, when the correct value is actually 40,000 km (25,000 mi).

3. Most scholars agreed with Ptolemy's estimate that Europe spanned 180° longitude, rather than the actual 130° or 150°. Columbus believed the even higher estimate of Marinus of Tyre, which put the longitudinal span of the European landmass at 225°, leaving only 135° of water.

And finally.......

4. He thought that he was in Asia when he was really in the New World!

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