Author: mayrazamudio

Astronomers use diffraction gratings to discover what stars and other glowing objects are made of. They do it by analyzing (or breaking apart) the light that comes from a star. Some stars give off light like this.  Put the hydrogen tube on its power supply, turn it on and turn off the white light. Make […]

Using filters is one way of separating light into its individual colors. Another way of separating light into its component colors is using a “diffraction grating.” Window D in your color analyzer is not just a clear window, it is a piece of plastic with thousands of parallel grooves called a diffraction grating. When light […]

We just looked at light reflected from objects like cloth. We will now look at how light goes through certain kinds of windows. I am handing out some devices that we call “color analyzers.” When you get yours, look for four windows—each of them labelled with the letters A, B, C, and D. VISUAL (alternative movie): Filters If your presentation is not using […]

Now, let’s go back to a red star and examine a piece of cloth (or color pattern on paper).Space travelers call it “the mystery cloth” because they have a hard time agreeing on the colors they see on it. Make sure only the red light is on. While you talk, start unrolling the multicolored cloth […]

Visit to a planet orbiting a red star DIGITAL EFFECT: Red LightFill the dome with red light to flood the planetarium, all other lights out.Alternatively, if your dome has its own red-green-blue lighting system (e.g., cove lighting), you may use that instead of the red light effect.[We are taking a liberty here: a real red […]

Columbus was certainly not the first person to explore the Americas. There is a lot of evidence that many other people visited the land we call the Americas, long before Columbus. As we discuss these early visitors, think about “how” they discovered the Americas. What route did they take? Were they expecting to discover the […]

Europeans learned how to use the compass that was invented in China. The Chinese inventions of paper and gunpowder were also useful to Europeans. Before the time of Columbus, European traders made long and tortuous overland journeys over thousands of miles to get to the Far East — China, India, Japan and Southeast Asia. Europeans […]

VISUAL 22 (still): Box CompassColumbus used a compass like this one, which he adjusted by the North Star just as we did a little while ago in China. Columbus also used a device known as a quadrant to find his latitude from the North Star. VISUAL 20 (still): Modern World Map with Latitude and Longitude […]

The North Star is good for telling navigators which way north is on clear nights. But to find your directions in the daytime or on cloudy nights, you need another device that was invented in China over a thousand years before Columbus made his famous voyages. Do you know what that device was?   [Compass.]Take responses. […]

Many ancient cultures devised ingenious ways to navigate and find their way, in their desire to explore and trade with other peoples in the world. In the process of trading, these navigation techniques were also traded. VISUAL 8 (still): African ShipArchaeological evidence suggests that around 2,800 years ago, African sea-roving traders may have sailed to present-day […]