Do you like observing the stars ? We usually see the stars outside. However, we can't see the stars in a cloudy sky. Then, you can made original planetarium which you can see the star signs you like.

Step 1: Gather Materials

To make this, you will need:

・Cardboard

・Cutter

・Tape measure

・Ruler

・Adhesive tape

・Pen

・Thumbtack

・Scissor

・Protractor

Step 2: Make a Skatch on the Cardboard

With everything prepared, it is tme to start making! Please make a skatch of 11 pentaons on the cardboards. When you make a skatch of pentagons, you have better use a protracter. In this way, you can make a skatch exactly.

Step 3: Cut the Cardboards

Let's cut the cardboards into pentagon with a cutter. Please try to make exactly, otherwise your planetarium will have some opening and a light will come through the opening. Take care that you don't cut your finger.

Step 4: Choose Star Signs

Let's search star signs and find eleven star signs that you like. I recommend the star signs which are made up of many stars such as the Scorpion and the Taurus because you can enjoy more dynamic night sky. This time, we choose the Scorpion, the Taurus, the Libra, the Leo, the Capricornus, the Gemini, the Virgo, the Pisces, the Aquarius and the Sagittarius.

Step 5: Draw Star Signs on the Cardboards

Because the star signs which is projected on the ceiling are reversed left and right, please draw the star signs on the back of the cardboards. Then you should write each name of the star signs to see what kinds of the star sign you can see.

Step 6: Make Holes Through the Cardboards

After drawing the star signs, you should make holes through the cardboards. If you use thumbtacks, you can make moderate size holes easily. Then, you should be careful that positions of stars are irregular. If you make many holes the starry sky will be more beautiful.

Step 7: Assemble Planetarium

Once you make holes, you should assemble 11 parts into a solid using an adhesive tape and a scissors. All sides of the parts are 8cm in length, so it is efficient to make many 8cm-long tapes and use them. Then, you should be careful not to make gaps between parts, or light will leak from the gaps. This process is a bit difficult, so it will be better to cooperate with others.

Step 8: Set Up Light

Once you assemble planetarium, you can use it. Planetarium needs a light, so you must prepare it. This time, use a smartphone’s light. If you have an electric bulb, to use it is better because its light spread like sphere. However, planetarium is made of cardboards, so you must be carefully about a fire if you use an electric bulb.

Step 9: Turn Down the Room Light

When you set up light, turn down the room light. If inside of the room is slightly bright, you cannot see your planetarium’s stars because its light is week. However, week light make a beautiful seeing like night stars.

Step 10: Let’s Enjoy Your Planetarium

Making planetarium is finished. Once that, to decorate planetarium is better. You can make only yours. This time, we use masking tape to decorate border of cardboards. You can be in deep thought about something or enjoy seeing stars with your friends while you use a planetarium. Let’s enjoy your planetarium! Thank you for reading.