ASTR 209 Lecture Notes - Solar Time, 61 Cygni, Minute And Second Of Arc

• School: University of Calgary
• Department: Astronomy
• Course: ASTR 209
• Professor: Ian Lovatt

Document Summary

Observations of the sun and the stars over a day (apparent diurnal motions) and over several months apparent diurnal motion of the sun (as seen from calgary) The description below is long, and therefore looks complicated. The sun appears on one horizon, seems to rise into the sky, travel through the sky, and disappear somewhere along the other horizon. When the sun reaches its highest altitude above, we say that the sun has reached its zenith. You can keep a record of the sun"s zenith with a sundial (actually, just a vertical stick in the ground a gnomon. You will do this in the last observing exercise. ) The stick casts a shadow; mark the end of the shadow. As the sun gets higher in the sky, the shadow 1) changes direction, and 2) gets shorter, and shorter. Eventually the sun gets lower in the sky, and the shadow gets longer and longer.