ASTR 1P01 Lecture Notes - Heel Stone, Angular Diameter, Mural Instrument

• School: Brock University
• Department: Astronomy
• Course: ASTR 1P01
• Professor: Bozidar Mitrovic

Document Summary

Classical greek astronomy: how ancient greek astronomers knew the earth is spherical. He used observations to form his views on the universe, eg. from the observations that when one travels south one can see new stars and constellations. He used observations to come up with this view of the universe: he concluded that the sun is at much greater instance from us than the moon. Assume the opposite, that the sun and the moon are at comparable distance from us. Earth sun distance: he obtained the value of 87 degrees (the actual value is 89 degrees and 53/60 degress < 59 minutes of arc. = 1/20 in other words the earth sun distance is 20 times larger than the earth moon: the actual value is 1/400. Than measured the moon to reemerge behind the shadow. Most planets are visible to the naked eye except for uranus and neptune. They they realized it"s just the same thing.