Astronomy 1021 Lecture Notes - Lecture 5: Deferent And Epicycle, Pseudoscience, Almagest

• School: Western University
• Department: Astronomy
• Course: Astronomy 1021
• Professor: Jan Cami

Document Summary

Supernova: stays in same spot, will fade over time. Large telescopes will show a fuzzy patch - the host galaxy. Comet: object moves, fuzzy patch in large telescopes is coma or tail; spectroscopic observations show presence of gases such as cyanide. Asteroid: object moves, no zzy patch should be visible and spectroscopy shows no gases. The hull effect (ship"s mast appears rst on sighting) Difference in the sky depending on latitude. Earth"s curved shadow on moon during lunar eclipses. Heard a report that on the longest at of the year shadows of columns disappeared in syene, egypt, sun is directly overhead. Used this to calculated the earth"s circumference. Distance between syene and alexandria is 7/360 of the earth"s circumference, then measured the distance (approx 42k) to nd circumference. Used phases of the moon to determine that the sun is much further away than the moon.