In this middle-school level activity, students work as NASA scientists to make repeated observations of our Sun and the planets to determine their rotation rates. First, students create a playground model of rotation and create representative diagrams. Students then observe NASA images of sunspots to determine the rotation rate of our Sun. In the last phase, students download NASA movies from the Internet and measure rotation rates for objects in the solar system.
Activity 1: Formulate explanations regarding the Earth's rotational period by watching satellite movies.
Changing Faces Teacher Lesson Plans
Using a classroom globe of Earth, ask students how long Earth takes to rotate once (24 hrs). Challenge students to explain how they know this. (students may suggest that we have movies of it taken by satellites that prove it. However, these movies have only been around for about 5 years. Before that, it was much more difficult to determine the rotation rate). Be certain students know the definition of rotation.
Change the focus of the discussion to the rotation of other planets. Ask students to develop and write out a strategy that they could use to determine the rotational rate of a distant planet.Exploration - Creating a playground model for rotation
During this outside phase, students are going to create a playground model for rotation by forming a rotating circle. One half of the class will be part of the circle and one half will observe from a distance; then, the groups will switch roles.
Create four different colored
construction paper signs and label each with a different object: mountain,
lake, crater and city. Place four students even distances apart along the
circle and hang the signs around their necks with string (or saftey pin
the signs to coats).
Students should combine the rotation rate results for team one and for team two on the blackboard. The focus of this part of the lesson is on how to determine rotation rates at a distance. First ask students to write down exactly the process they used to measure the rotation rate of the circle using the reference signs. Second, have students create two sketches of the scenario: (1) as viewed from eye level and (2) as viewed from above. See the pictures below as examples. Tell students that they will be using this same observational process to determine the rotation rate of our Sun.
Measuring solar rotation rates
View solar image number 001. Notice the location of these spots on the solar surface. Now look at solar image number 002. Where are the spots now? You should note that on the bottom of each image is a time and date mark. These will be very helpful in determining the rotation rate for our Sun. Solar image number 003 appears on a page with lots of additional solar images.
Determine the rotation rate of our Sun by watching sunspots move from one side to the other, or by looking at the sequence of pictures. It should be close to 25 days. This is how Galileo determined the solar rotation rate in 1610. An animated image of solar rotation is available too!
Arrange students into 4-member NASA science teams and assign to each team one of the following solar system objects. Teams should create a multi-media report that includes six parts: