Three Ways to Make a Solar Eclipse Viewer
Child using box eclipse viewer (NASA via YouTube)
Child using box eclipse viewer (NASA via YouTube)
How does this align with my curriculum?
Safely view a solar eclipse by making and using a pinhole solar eclipse viewer.
Materials:
- Aluminum foil
- Thumbtack, pin or sharp pencil*
- Tape
- Scissors*
- Box cutter or craft knife*
- White paper
- Choice of: cardboard, cardstock, a paper towel tube or a cardboard box. Shoe boxes are great, but others will work as well.
*Adult help may be needed for poking holes and cutting cardboard.
What to do!
Here are three different ways of making a safe eclipse viewer.
#1 Simple Viewer
All you need is a piece of cardboard, a pin and a sheet of white paper.
- Poke a small hole in the centre of the cardboard with the pin or other pointed object.
- Put the white paper on the ground.
- Stand with your back to the Sun. Hold the cardboard at a right angle to the path of the Sun. Move the cardboard until you see its shadow on the paper. You should see a small bright circle in the shadow. Remember - do not look at the Sun - only look at the image of the Sun on the paper.
Image - Text Version
Shown is a colour diagram of sunlight shining through a hole in a piece of cardboard onto a sheet of paper. A yellow circle labelled “Sun” is in the top left corner of the diagram. A pale yellow triangle stretches diagonally down and to the right across a white background. This ends in a point at the centre of a flat brown square. This is labelled “Pinhole.” The square floats some distance above, and parallel to the horizon. A narrower, pale yellow triangle stretches from here, diagonally down and to the right, past the horizon. It ends in a yellow dot in the centre of a white square. The white square is labelled “Paper on the ground.” The yellow dot is surrounded by a smaller grey square labelled “Shadow caused by cardboard.” The ground below the horizon is brown.
Tips and Hints
If you don’t have cardboard, a piece of bristol board or an index card will also work.
#2 Box Viewer
For a more complex viewer, you can use a cardboard box.
- Cut a piece of paper that is the same size as one of the small ends of the box. Tape the paper to the inside of the box.
- Cut a small rectangular hole in the upper left corner of one side of the box. This should be on the side opposite to the one with the paper.
- On the same side, cut a large viewing hole in the upper right corner.
- Cut a piece of aluminum foil a bit larger than the small hole.
- Poke a small hole in the centre of the aluminum foil.
- Tape the aluminum foil over the small hole.
- With your back to the Sun, hold the cardboard box at a right angle to the path of the Sun. Put the large viewing hole up to your eye. Make sure the smaller hole is not covered. Move the viewer until a small bright white circle appears on the paper.
Image - Text Version
Shown is a colour diagram of sunlight shining through a hole in a grey square on the side of a brown box, onto a white square inside. A narrow yellow triangle points diagonally down from the top left edge of the illustration. This is labelled “Sunlight.” It ends in a black dot in the centre of the small grey square. The dot is labelled “Pinhole.” The grey square is labelled “Aluminum foil taped over a small hole.” Both of these are in the top left corner of the left side of a rectangular box labelled, “Cardboard box.” A larger square hole is cut into the top right corner of the same side of the box. The near side of the box appears open. This area is labelled “*side cut away to show the inside of the box.” Inside the box, another narrow, yellow triangle starts from the other side of the pinhole at the top left, diagonally down and to the right. This ends in a white crescent shape in the centre of a pale grey square. This is labelled “Paper,” and attached to the right inside wall of the box.
Tips and Hints
If using a cereal box, cut the flaps off of the top or bottom end. Tape aluminum foil over half of the opening. Add a pinhole to the centre of the foil. With your back to the Sun, look into the box through the opening beside the foil.
#3 Tube Viewer
You can also try this hand-held viewer, using a cardboard or thick paper tube.
- Trace the opening of the tube on a piece of white paper. Draw a slightly bigger circle around it. Cut around the bigger circle. Cut small slits to the inner circle.
- Cut an opening near one end of the tube to make a viewing window.
- Tape the paper circle to the end of the tube near the viewing window.
- Cut a piece of aluminum foil that is a bit larger than the opening of the tube.
- Poke a small hole in the centre of the aluminum foil.
- Tape the aluminum foil over the other opening of the tube.
- With your back to the Sun, hold the tube parallel to the path of the Sun. Look through the viewing hole. Move the viewer until a small white circle appears on the paper.
Image - Text Version
Shown is a colour diagram of sunlight shining through a hole in one end of a brown tube and onto paper across the other. A narrow yellow triangle labelled “Sunlight” points diagonally down from the top left corner of the illustration. This ends in a black dot in the centre of grey material stretched across the end of a cylinder. The material is labelled “Aluminum foil,”the dot is labelled “Pinhole,” and the cylinder is labelled “Cardboard or paper tube.” Translucent strips holding the foil to the tube are labelled “Tape.” A square window near the right end of the tube is labelled “Viewing window cutout.” Inside the tube, a yellow beam of light can be seen ending in a bright white circle on white paper. This is labelled “Paper taped to opening.” In the lower left corner, a smaller diagram shows a close-up view of this, labelled “Paper.” Two concentric circles are drawn on it in black. Short lines radiate from the inner circle to the outer one. The inner circle is labelled “Tracing of paper tube.” The outer one is labelled “Cut here.” The short lines are labelled “Cut slits.”
Tips and Hints
If you don’t have a cardboard tube, you can make your own. Roll a piece of cardstock or several sheets of dark construction paper to form a tube. Then tape it together well, so no light gets through the sides.
Discovery
What is a solar eclipse?
During a solar eclipse, the Moon casts a shadow on the Earth. This happens when the Moon passes between the Sun and Earth. As it does so, it blocks some or all of the Sun’s rays. Scientists call the area of darkness caused by an eclipse the penumbra. The darkest part of the penumbra is a small area in the centre. This is called the umbra.
The solar eclipse on April 8, 2024, is a total solar eclipse. A total solar eclipse happens when the Moon completely covers and blocks the light from the Sun. The path of the penumbra will cross over Canada, the United States and Mexico.
Image - Text Version
Shown is a colour diagram of the positions of the Sun, Earth and Moon during a solar eclipse. The illustration is titled “Solar Eclipse.” It shows the Sun as a yellow circle on the left, the Earth as a blue circle on the right, and the Moon as a grey circle between the Earth and Sun. The Sun’s light is shown as a light blue cone extending from the Sun to the right towards the Earth and moon. The light blue cones of sunlight meet in between the Sun and moon, casting a circular shadow on Earth. The darkest part of the shadow is a small dot in the centre. This is the apex of the Moon’s umbra.
Image - Text Version
Shown is a colour diagram of the Sun, Moon and Earth during a solar eclipse. The Sun is shown as a yellow half-circle on the left. Earth is shown as a blue circle on the right. Between is a circle representing the Moon. The half of the moon facing the Sun is light gray and the half of the moon facing the Earth is black. A cone of dark gray extends from the Moon to the Earth. This represents the darkest part of the Moon's shadow on Earth. The area where this shadow is on Earth is labelled "Umbra". A larger pale gray cone extends from the Moon to the Earth. This represents the less dark part of the Moon's shadow on Earth. The oval area where this shadow appears on Earth is labelled "Penumbra".
How do pinhole viewers work?
Did you know that light always travels in a straight line? Light from the Sun travels outwards in straight lines. Some of those lines, or “rays”, of light will pass through the pinhole in your paper or foil. On the other side, the rays of light keep going until they hit the paper. The image of the Sun on the paper is upside down and backwards because the light rays cross over each other as they travel through the tiny hole.
Image - Text Version
Shown is a colour diagram of lines travelling from the Sun, through a pinhole and onto a piece of paper to form a crescent. In the top left corner, a small grey disk labelled “Moon,” sits in front and to the right of an orange one labelled “Sun.” A blue line extends from the top edge of the Sun and an orange one from the bottom. These stretch diagonally down to the right. They come to a point labelled “Pinhole” in the centre an orange square. On the other side of this square, the orange line emerges on top, and the blue below. They stretch apart, moving diagonally down to the right until they hit a pale grey rectangle labelled “Piece of paper.” In the centre of this is a white crescent shape. The orange line intersects with the top edge of the crescent, and the blue one with the bottom.
Eclipse Safety
Solar eclipses are pretty cool to watch, but you need to be careful. The light from the Sun is so bright that it can be dangerous to look at directly. This is true every day, not just during an eclipse! Looking directly at the Sun for even a few seconds can cause permanent damage to the retina in your eye. This part of the eye collects information about light and colour.
Here are some tips for safe solar eclipse-watching:
- Always wear approved eclipse glasses when looking at the Sun. You can check if glasses are approved/certified for solar viewing by looking for an ISO certification rating written on them.
- NEVER look at the Sun using regular sunglasses or through black garbage bags. These do not block enough of the Sun’s rays.
- Safer still is watching an eclipse using your pinhole viewer!
- If you made the basic viewer, try moving the cardboard closer to and farther away from the paper. What do you notice about the image?
- Try adding tubes together to make an even longer viewer. What do you notice about the image on the longer viewer?
- Find out when the next solar eclipse will appear near you, using a calendar such as the one at timeanddate.com.
Get Ready for a Total Solar Eclipse! (2023)
Learn about the different solar eclipses including how they happen and where they can be seen in this backgrounder by Let’s Talk Science.
Introducing the Sun (2023)
Learn the basics of the star we call the Sun in this backgrounder by Let’s Talk Science.
The Earth Moon System (2022)
This backgrounder by Let’s Talk Science has answers to some common questions about Earth’s Moon.
How to safely watch a solar eclipse (2024)
This page from the Canadian Space Agency has a video about how to safely watch a solar eclipse as well as links to other eclipse resources.
How We See (2022)
Did you know that the pupil in your eye works in a similar way to the pinhole in a pinhole viewer? Find out more about how your eye works in this backgrounder by Let’s Talk Science.
Light and Its Properties (2022)
Learn more about light and its properties in this backgrounder by Let’s Talk Science.
What’s happening?
What is a solar eclipse?
During a solar eclipse, the Moon casts a shadow on the Earth. This happens when the Moon passes between the Sun and Earth. As it does so, it blocks some or all of the Sun’s rays. Scientists call the area of darkness caused by an eclipse the penumbra. The darkest part of the penumbra is a small area in the centre. This is called the umbra.
The solar eclipse on April 8, 2024, is a total solar eclipse. A total solar eclipse happens when the Moon completely covers and blocks the light from the Sun. The path of the penumbra will cross over Canada, the United States and Mexico.
Image - Text Version
Shown is a colour diagram of the positions of the Sun, Earth and Moon during a solar eclipse. The illustration is titled “Solar Eclipse.” It shows the Sun as a yellow circle on the left, the Earth as a blue circle on the right, and the Moon as a grey circle between the Earth and Sun. The Sun’s light is shown as a light blue cone extending from the Sun to the right towards the Earth and moon. The light blue cones of sunlight meet in between the Sun and moon, casting a circular shadow on Earth. The darkest part of the shadow is a small dot in the centre. This is the apex of the Moon’s umbra.
Image - Text Version
Shown is a colour diagram of the Sun, Moon and Earth during a solar eclipse. The Sun is shown as a yellow half-circle on the left. Earth is shown as a blue circle on the right. Between is a circle representing the Moon. The half of the moon facing the Sun is light gray and the half of the moon facing the Earth is black. A cone of dark gray extends from the Moon to the Earth. This represents the darkest part of the Moon's shadow on Earth. The area where this shadow is on Earth is labelled "Umbra". A larger pale gray cone extends from the Moon to the Earth. This represents the less dark part of the Moon's shadow on Earth. The oval area where this shadow appears on Earth is labelled "Penumbra".
How do pinhole viewers work?
Did you know that light always travels in a straight line? Light from the Sun travels outwards in straight lines. Some of those lines, or “rays”, of light will pass through the pinhole in your paper or foil. On the other side, the rays of light keep going until they hit the paper. The image of the Sun on the paper is upside down and backwards because the light rays cross over each other as they travel through the tiny hole.
Image - Text Version
Shown is a colour diagram of lines travelling from the Sun, through a pinhole and onto a piece of paper to form a crescent. In the top left corner, a small grey disk labelled “Moon,” sits in front and to the right of an orange one labelled “Sun.” A blue line extends from the top edge of the Sun and an orange one from the bottom. These stretch diagonally down to the right. They come to a point labelled “Pinhole” in the centre an orange square. On the other side of this square, the orange line emerges on top, and the blue below. They stretch apart, moving diagonally down to the right until they hit a pale grey rectangle labelled “Piece of paper.” In the centre of this is a white crescent shape. The orange line intersects with the top edge of the crescent, and the blue one with the bottom.
Why does it matter?
Eclipse Safety
Solar eclipses are pretty cool to watch, but you need to be careful. The light from the Sun is so bright that it can be dangerous to look at directly. This is true every day, not just during an eclipse! Looking directly at the Sun for even a few seconds can cause permanent damage to the retina in your eye. This part of the eye collects information about light and colour.
Here are some tips for safe solar eclipse-watching:
- Always wear approved eclipse glasses when looking at the Sun. You can check if glasses are approved/certified for solar viewing by looking for an ISO certification rating written on them.
- NEVER look at the Sun using regular sunglasses or through black garbage bags. These do not block enough of the Sun’s rays.
- Safer still is watching an eclipse using your pinhole viewer!
Investigate further!
- If you made the basic viewer, try moving the cardboard closer to and farther away from the paper. What do you notice about the image?
- Try adding tubes together to make an even longer viewer. What do you notice about the image on the longer viewer?
- Find out when the next solar eclipse will appear near you, using a calendar such as the one at timeanddate.com.
Learn More
Get Ready for a Total Solar Eclipse! (2023)
Learn about the different solar eclipses including how they happen and where they can be seen in this backgrounder by Let’s Talk Science.
Introducing the Sun (2023)
Learn the basics of the star we call the Sun in this backgrounder by Let’s Talk Science.
The Earth Moon System (2022)
This backgrounder by Let’s Talk Science has answers to some common questions about Earth’s Moon.
How to safely watch a solar eclipse (2024)
This page from the Canadian Space Agency has a video about how to safely watch a solar eclipse as well as links to other eclipse resources.
How We See (2022)
Did you know that the pupil in your eye works in a similar way to the pinhole in a pinhole viewer? Find out more about how your eye works in this backgrounder by Let’s Talk Science.
Light and Its Properties (2022)
Learn more about light and its properties in this backgrounder by Let’s Talk Science.