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1.
Go to the Earth's Seasons webtool at http://janus.astro.umd.edu/astro/seasons
website.
a) Run the defaults for Christchurch (latitude 43.5
degrees south). How many hours of sunlight do we get in mid summer?
Mid winter?
b) How do these numbers change for Dr. Hamilton's
hometown of Anchorage Alaska at latitude 60 degrees north?
c)
Describe the amount of sunlight received during the year for someone
at the equator.
d) What is special about the Antarctic Circle and
the Tropic of Capricorn?
e) Explore seasons on a few of the
other planets - what if Earth were tilted like Mercury or Uranus (see
helpfile)?
f) Finally, under what conditions would Earth's
Antarctic Circle be north of its Tropic of Capricorn?
2. Changing Perspectives: A view from the Moon. The same side of the
Moon always faces the Earth. Assume you live on the Moon near the
centre of the face that points towards Earth.
a) Where in your sky would you see the Earth?
b) Describe how the Earth would appear to move in the sky.
c) Suppose you see a full Earth in your sky. What phase of the Moon
would people of the Earth see? Draw a picture and explain.
d) Suppose people of Earth see a full Moon. What phase would you see
for the Earth? Draw a picture and explain.
e) Suppose people on Earth are viewing a total lunar eclipse. What
would you see from your home on the Moon? Explain.
3. Explore the Solar System. The Solar System consists of planets and
minor bodies (asteroids and comets) that orbit the Sun and moons
that orbit the planets. Go to the Solar System Visualizer program at
http://janus.astro.umd.edu/SolarSystems.
Start with the Solar System, using the + and - keys to zoom in and
out.
a) Which way do the planets orbit the Sun, clockwise or
counterclockwise?
b) Now click on each of the planet names in
the upper left menu (if nothing happens, the planet has no moons). How
many moons do the terrestrial planets Mercury, Venus, Earth, and Mars
have? Do these orbit clockwise or counterclockwise?
c) Now look
at each of the giant planets - what are the main differences between the satellite systems of the terrestrial and giant planets?
d) Finally, check out Pluto. In terms of moons, is Pluto more like a terrestrial or giant planet?