ASTR 1150 Lecture Notes - Lecture 1: Celestial Pole, Celestial Equator, Azimuth
Document Summary
Astr 1150 - lecture 1: introduction to stars and galaxies. Stars are extremely large and massive, made of gases and metals. The sun is roughly 100 earth"s across and has a mass roughly 1 million that of the earth. 100,000,000,000 starts (100 billion), separated by lightyears. Neptune is 4. 5 billion kilometers from the sun. The closest star is 40 trillion kilometers from the sun, which is about 10,000 kilometers further than neptune. Imagine 100 billion stars, each 40 trillion kilometers from each other. Hundreds of billions of galaxies organized in patterns still being studied and understood. Viewing the night sky: directions, constellations and stars. Describing the positions of objects in the sky- in addition to identifying objects, observers must be able to describe their position in the sky to other astronomers: local system - altitude and azimuth. Altitude is estimated in degrees (you can use your hands or a protractor for this)
