Module 2 Activity: Part 2

Geocentric vs. Heliocentric: Looking at Venus from Earth

In Part 2 of Module 2's activity, we'll use some computer `simulators' to see what Venus would look like, as seen from the Earth. We're going to compare and contrast what we would expect to see in both of the major `models' of the solar system: Geocentric and Heliocentric.

Before we start, here's a quick reminder about something in case you need it... You'll be giving your answers in "clock face positions", like "3 o'clock" or "9 o'clock". If you mostly use a digital watch or phone to check the time, these "o'clocks" might be unfamiliar to you. Here's a picture of a clock face in case you need a reminder. Also, the terms "clockwise" and "counterclockwise" will probably come up later in the quarter, so here's a reminder of those terms, too:

Let's imagine you lived in the Europe of the early 1600s, when Galileo made the first observations of Venus with a telescope. With the unaided eye, Venus only ever looks like a bright, starlike point in the sky. However, with a telescope, it looks big enough to show a disc, and that disc can show phases, like the Earth's Moon.

The questions here in Part 2 of the Module 2 Activity use two computer simulations. They show where the Earth, Sun, and Venus are in each model, and they show what Venus would look like through a telescope. You may need to enable Flash in your browser in order for the animation to work properly:

Questions 1 through 4 use this one - the Geocentric (a.k.a. Ptolemaic) model.

Right-click on the image below, and open it in a new browser tab or window. Then answer Questions 1 through 4. You may need to enable Flash if your browser asks you to.

Questions 5 through 8 use this one - the Heliocentric (a.k.a. Copernican) model

Right-click on the image below, and open it in a new browser tab or window. Then answer Questions 5 through 8. You may need to enable Flash if your browser asks you to.

Once you've answered Questions 5 through 8, go on and answer Questions 9 and 10. You may need to go to the tabs containing the two simulator and play with them while you're thinking about your answers to Q9 and Q10.

Your scores and feedback comments for this part of the Module 2 Activity will be available October 16 at 10pm.