north

/Tag: north

Islamic geographers – Medieval Islam

By |2019-07-03T10:11:08-07:00July 25th, 2017|History, Islam, Science|

Islamic geographers: al-Idrisi's map of the world (1100s AD) Universities in the Islamic Empire Silk Road and Indian Ocean trade made many people in the Islamic Empire rich enough to send their sons to college. So the big university at Alexandria in Egypt stayed open. But the university moved from Alexandria to the nearby town [...]

What is an astrolabe? Greek science

By |2019-02-04T09:56:46-07:00July 16th, 2017|Greeks, Science|

An Islamic astrolabe (832 AD) Who invented the astrolabe? About 140 BC, the Greek astronomer Hipparchus of Rhodes invented the science of trigonometry. What's trigonometry?  Greek astronomy History of astronomy All our Ancient Greece articles Hipparchus figured out that you could use an imaginary right triangle whose corners were the sun, the earth, and the planets or stars, to calculate the movements [...]