Hooked on science: Eclipse box

Ingredients

• Long cardboard box
• Scissors
• Tape
• Aluminum foil
• Thumb tack
• 8-by-11-inch white copy paper

Instructions

• Step 1: Cut a 4-by-2-inch rectangular hole in the end of the long cardboard box.
• Step 2: Cut out a piece of aluminum foil slightly larger than the rectangular hole in the end of the box.
• Step 3: Tape the aluminum foil over the rectangular hole in the end of the box.
• Step 4: Using the thumb tack, create a tiny hole in the center of the aluminum foil.
• Step 5: Tape the copy paper on the inside of the other end of the box. Close and tape the box.
• Step 6: Cut a hole big enough for your head in the bottom of the box.
• Step 7: Stand with your back to the sun. Place the box over your head, with the aluminum foil towards the sun. Adjust your position until you see a small projection of the eclipsed sun on the paper. Use the observations of the sun, moon and stars to describe how patterns can be predicted. Create an argument that differences in the apparent brightness of the sun, compared to other stars, is due to their relative distance from the Earth.

Explanation

Your solar-eclipse box works like a pinhole camera. A pinhole camera is a simple camera without a lens. Light from the sun travels through the thumb-tack hole and projects an inverted image of the eclipse onto the white paper.