The science activities in this module deal with the concept of travel as it relates to natural objects (planets) traveling around the sun. The activities are designed to let the students discover Kepler's Laws of Planetary Motion by completing assignments about the laws.

In the first activity, "Round and Round," students are given some historical context by reading background information about Nicolaus Copernicus, Tycho Brahe, and Johannes Kepler. Students then construct an ellipse using two different methods. They discover that planets orbit around the sun in elliptical orbits (first law). Using one of these ellipses, students are introduced to the concepts of the focus and the semi-major axis of an ellipse. Using these concepts, they determine the eccentricity of an ellipse and compare this with the relative roundness of the planetary orbits.

In the second activity, "Sweepstakes," students learn that as a planet travels around the sun, at different points it sweeps out equal areas in equal times (second law).

In the third activity, "The Inclined Pendulum," using a simulation, students model the fact that a decrease in gravity causes a decrease in orbital velocity and those more distant planets revolve around the sun at slower velocities (third law).

Finally, the students conclude by reading the Student Text, "L1 or Bust." They learn about the LaGrange Points and study the trajectory that is used by the Genesis spacecraft.

In "Minimum Energy Transfer Orbits," students will study the mathematics involved in having a spacecraft move from one orbit to another. They will use a mathematical formula derived from Kepler's Third Law of Motion (see "The Inclined Pendulum") to calculate the time of flight that a spacecraft would take to travel from Earth to another planet in our solar system using the minimum amount of energy. Students will look at the formula derived from Kepler's Third Law and make some simple calculations. Once students have calculated time of flight to one or more planets, they can use an Excel spreadsheet to investigate other transfer orbits as a technology application.

Using a surprisingly simple relationship, Kepler's Third Law, we can study the orbit of a spacecraft about a body in space. We can study the basic parameters of (1) the time our spacecraft will take to circle the body once (called the "Period") and (2) its average distance from the body (we will call this "A"). Kepler came up with this law in 1619 after having spent the previous 19 years studying the best data on the orbit of Mars. This equation is empirical, that is, based on the very careful analysis of data.

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A technology communication theme that deals with both strands will also be utilized. Both disciplines use two short stories by Ray Bradbury that function as springboards for these activities. The first is "Golden Apples of the Sun," and the second is "The Wilderness."

Both stories are rich with opportunities to develop students' critical thinking and communication/language arts skills; both stories have a strong science application that advance science inquiry processes.

Before they begin, students will be asked to provide their own definitions of communication-a seemingly easy task that soon becomes complicated and always results in a spirited classroom discussion.