Science of Technology

As an object moves, a “dot pattern” creates a record of the object's location at regular time intervals. This data can be used to reinforce a variety of physics lessons.

First, acceleration can be detected when the spacing of the dot patterns changes, while constant velocity is indicated by a regular spacing.

Second, these periods of acceleration match the use of thrusters in a deep-space rocket.

Third, just as a force is needed to increase a rocket's speed, a force is also needed to slow it down.

Finally, the data in these dot patterns can be converted easily to a velocity time graph, which can be used to find both periods of acceleration (non-zero slope) and displacement (area under curve).

This interactive asks users to control the rocket (lunar lander) using two thrusters in order to produce a safe docking (not too fast) with the second rocket (lunar orbiter) at the right of the screen. shows a dot pattern as thrusters are used (either by clicking the thruster arrows or using the keyboard arrow keys).

At all levels of this interactive, the dot pattern is shown at the top of the screen, and the pattern can be downloaded using the button in the lower left. Physics students could be challenged to analyze or replicate a dot pattern provided to them, or analyze the key moments in the pattern they created.

At the Pink level, a velocity-time graph is constructed in real time, and a screenshot download could be used for similar purposes.

At the Yellow level, three tracks with streams of space junk pass between the lander and the orbiter. Users are challenged to adjust the speed of the rocket in order not to be hit by the bit of junk. (There are random factors built into this section, so each attempt will be different. I have made both successful and unsuccessful runs.)

There are a number of scenes in the awesome HBO series “From the Earth to the Moon” that show dramatizations of this scenario.