By heaven man, we are turned round and round in this world, like yonder windlass, and Fate is the handspike Herman Melville, Moby Dick

Assignment: Reading: Explorations, pp. 19-28 If you haven't emailed me yet, do it this weekend. Tell me what you'd like to be called and describe something interesting about yourself. It should also include the statement "I have read the online Course Description and understand what is expected of me in this course." Start working on Problem Set #1, which is due next Thursday at 1pm. Sign up for a time slot for Observing Lab #1.

In Class: Question to Ponder Sailors on the ships Columbus sailed westward from Spain in 1492 were afraid of a) falling off the edge of the earth. b) meeting up with violent native American civilizations. c) becoming becalmed in the Bermuda Triangle. d) starving to death during an ocean voyage of unknown length. How to Know Which Way is "Up" gravity points "down" "Up" is the direction perpendicular to all horizons On a sphere, the "up" direction depends on where you are Stars Define a Direction, Not a Position Stars are so distant that lines from anywhere on Earth to a given star are parallel. The Altitude of a Given Star Changes as You Move About on a Curved Earth Altitude is the angle between the direction to the star and the direction of the horizon. For a Flat Earth, a star's altitude would not depend on location.