Remote sensing has been defined as "a technique used to gather information about an object or an area without actually touching it" Our eyes, ears, and skin, as well as more sophisticated instruments, all aid us in remote sensing. These sensors provide information about size, color, location, temperature, and other conditions.
Find examples of remote sensing in your everyday experience.
- Ask students to give examples of remote sensing based on the above definition. (Answers may include: smelling dinner cooking, taking a photograph, feeling heat from a fire, seeing lightning strike, observing stars through a telescope, reading an X-ray, etc. )
- Introduce the scents to children as a group so they can recognize them later.
- Create a smell trail around the classroom by soaking pieces of cloth with strong, scented oils. Place the cloth pieces around the room. (It isn't necessary to hide them, unless you wish to make the activity harder.)
- Provide (or have children construct) a diagram or map of the classroom showing exits, windows, students' desks, teacher's desk, and any other important "landmarks."
- Have students try to locate scents by "remote sensing," using their noses.
- Have them make X's on the map to indicate the locations of scents. (To make the activity more challenging, assign a different color to each scent and make a key or legend to show what scent each color represents.)
- Ask students how they can find hot spots and cold spots in the classroom or playground by remote sensing.
- Use the same classroom diagram to make a sensory map of the classroom (or school grounds) to mark hot spots and cold spots.
- Use an H for hot or warm (near the radiator, a sink filled with hot water, a sunny window), C for cold (near a door, a fan, an open window) (The teacher may want to set up hot and cold spots beforehand.)
- Explain that a satellite detects temperature differences and sends back information to create an infrared image in black and white and shades of grey. Color may be added by the computer to accentuate temperature differences by assigning different colors to represent different temperatures. Warm areas might appear as green, cold areas as yellow.
These colors do not represent the actual colors of the Earth's surface. They are called false colors, because they are not the same colors that would be seen in a normal color photograph of the area. Our eyes and conventional cameras can't visually detect the difference between hot and cold. We rely on other senses to do that.
- Have students color a classroom map to indicate warm (perhaps represented by pink or red) and cold areas (represented by blue), as they might appear on a satellite image showing temperature variations.
- pieces of cloth
- markers or crayons
- infrared satellite image
- oils of various scents: peppermint, musk, garlic, lemon, perfume.