# Week 6

Read: From Astronomy to Cartography (Chap. 9) and Climates and Continents (Chap. 10). Actually, you can skip Chap. 10.
Quiz: Monday. Covers Bede's The reckoning of time.

Homework exercises: Latitudes (Ex. 9.1), Waldseemuller's worldview (Ex. 9.2). Due noon Saturday week 6.

Laboratory exercises: Latitude and longitude observations (Ex. 9.3). For the latitude observation, you should find and measure the altitude of Polaris using your cross staff during any evening this week. For the longitude observation, you should go out on a sunny day around noon, set up a small vertical stick, and use a sheet of paper to measure the length of the shadow every five minutes between 12:30 and 1:30 pm. From this, you can determine the precise time that the shadow is shortest (local noon). To aid your thinking about this, you might consider that if the sun passes the local meridian at noon in Greenwich, England, then if a British sailor travels a quarter of the way around the globe toward the Americas (90 degrees west in Longitude), then he will experience the sun pass the new local meridian 6 hours later. In other words, by observing the time that the sun passes the local meridian, one can determine his or her longitude. There is an intimate connection between astronomy, time measurement, and navigation. For each exercise, you should make a scan of your lab book that includes data tables, sketches, and calculations of latitude and longitude. This is due noon Monday week 7. Also, don't forget to submit your weekly planetary observation on Monday of week 7.

From astronomy to cosmography (3 videos):

Climates and continents (no videos yet…):

The French Revolutionary calendar
was introduced, along with the metric system, by the French Revolutionaries in the early 19th century. They tried to make a base-10 system of time measurement, like the base-10 system of distance measurement. This new calendar system rejected traditional saints days and other holy days. Here is an interesting article on the French Revolutionary Calendar.
Intro. to Astronomy