Basic Coordinates & Seasons – Student Guide
There are three main sections to this module: terrestrial coordinates, celestial equatorial
coordinates, and understanding how the ecliptic is related to seasons on the Earth. Each
of these sections has its own simulator(s). The background material necessary to utilize
these tools is contained in each section.
Work through the explanatory material on units of longitude and latitude, finding
longitude and latitude, and a bit of history (optional).
Open the flat map explorer.
Familiarize yourself with the cursor and how it prints out the longitude and
latitude of the active map location.
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East (there are two ways
of thinking about this)
Question 3: The exact coordinates of the white house in Washington D.C., are 77.0365º
W and 38.897º N. What are these exact coordinates in sexagesimal notation? Show your
calculation in the box below. (You can use the Google Map tool to check your answer.)
Open the globe explorer. You are encouraged to use the Terrestrial Coordinate
Explorers link which opens both simulators at the same time for the following two
questions. Familiarize yourself with the features noting that they are very similar
to those in the flat map explorer.
Question 4: A) Where is the north pole on the flat map explorer? What is its shape?
B) Where is the north pole on the globe explorer? What is its shape?
C) Your answers to parts A and B should be different. Explain why.
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Question 5: Compare the relative sizes of Greenland and Australia in the two maps? The
true values of the surface areas for these countries are Greenland (2.2 million km2) and
Australia (7.7 million km2). Does each map demonstrate these true values?
Celestial Equatorial Coordinates
Work through the introductory material on the page entitled Celestial Equator,
Declination, Right Ascension.
Open either the Flat Sky Map Explorer or the Sky Map Explorer.
Familiarize yourself with the same set of features (cursor movement, shifting the
map, decimal/sexagesimal) that were available on the previous maps.
Make sure that you understand what each check box does.
Question 6: Where is the star Polaris located on this map? What are its coordinates?
Question 7: Find the constellation of Orion shown in the box below and measure the
right ascension and declination of its brightest stars Betelgeuse and Rigel. Note that
Orion is located on the celestial equator.
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Question 8: Which direction is east on the flat sky map? Relate this to a coordinate of the
celestial equatorial system.
Question 9: Complete the following table of positions on the ecliptic.
Question 10: Write out a description of the ecliptic on the flat sky map. What does the
shape look like? Describe the ecliptic in terms of its average and range of declination
Seasons and the Ecliptic
Work through the introductory material on the page entitled Orbits and Light.
Open the Seasons and Ecliptic Simulator.
Note that there are three main panels (left, upper right, and lower right) each of
which have two different views. Controls run along the bottom of the simulation
that affect more than one panel. Click animate and then move through the six
views to get...