Week 6 (Sep. 30 - Oct 4)
Read: From Astronomy to Cartography (Chap. 9) and Climates and Continents (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 exercise, you should find and measure the altitude of Polaris using your cross staff during any evening this week. How does this tell you the latitude of your observation point? Explain.
For the longitude exercise, you should go out on a sunny day around noon, set up a small vertical stick (gnomon), and use a sheet of paper to measure the length of the shadow every five minutes between about 12:30 and 1:30 pm. Draw a line from your gnomon to the end of the shadow for each measurement. Make a data table that lists the time on your clock and the length of the shadow at that time. Then make a plot your shadow length (vertical axis) versus the time of day (horizontal axis). Put all of this data and analysis in your lab notebook. From your data, you should be able to determine the precise time that the shadow is shortest (local noon).
How can you determine your longitude based on your measurements? To aid your thinking, you might consider that if the sun passes the local meridian at noon in Greenwich, England, then if a British a quarter of the way around the globe toward the Americas (90 degrees west in Longitude), then he will see the sun pass the new local meridian 6 hours later than his companion back in England. 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.
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 exercise, you should find and measure the altitude of Polaris using your cross staff during any evening this week. How does this tell you the latitude of your observation point? Explain.
For the longitude exercise, you should go out on a sunny day around noon, set up a small vertical stick (gnomon), and use a sheet of paper to measure the length of the shadow every five minutes between about 12:30 and 1:30 pm. Draw a line from your gnomon to the end of the shadow for each measurement. Make a data table that lists the time on your clock and the length of the shadow at that time. Then make a plot your shadow length (vertical axis) versus the time of day (horizontal axis). Put all of this data and analysis in your lab notebook. From your data, you should be able to determine the precise time that the shadow is shortest (local noon).
How can you determine your longitude based on your measurements? To aid your thinking, you might consider that if the sun passes the local meridian at noon in Greenwich, England, then if a British a quarter of the way around the globe toward the Americas (90 degrees west in Longitude), then he will see the sun pass the new local meridian 6 hours later than his companion back in England. 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.