1:45 PM - 3:15 PM
[O11-P25] NPAD & SP(Newspaper Air Dome & Star Projector)~the portable Planetarium~
Keywords:Planetarium
Purpose and Background Facilities capable of screening planetarium shows are limited. Therefore, we, the Planetarium Team of the Astronomy Club at Yokohama Municipal Sakuragaoka High School, thought that with a portable dome and projector, we could easily present planetarium shows anywhere. Thus, we embarked on this production, emphasizing "affordability" and "lightness" as key objectives.
Production of NPAD (News Paper Air Dome)
2.1. Criteria
In constructing the dome, we focused on "affordability" and "lightness," and added the requirement of a "hemispherical" shape. This design choice aligns with how our eyes perceive stars as being at a uniform distance, creating a hemispherical impression of the night sky. Considering these criteria, we decided to create a 4-meter diameter hemispherical air dome made from newspaper, named News Paper Air Dome (NPAD).
2.2. Method Measure a 50 cm diameter globe at every 15° latitude and 10° longitude, recording values to two decimal places (only the polar region is measured at a 6.4° latitude). Multiply the measurements by 8, and create 24 trapezoidal parts and one circular polar region part using newspaper. Assemble these parts using glue sticks and masking tape. Attach 60 cm tall cardboard to the lower half of the dome using masking tape to reduce distortion and prevent light from shining into the audience's eyes.
2.3. Results and Challenges NPAD functioned effectively as a space for projecting stars with minimal distortion. When not in use, it can be reduced to a minimum size of 60 cm and inflated in about 5 minutes using a fan. Challenge: NPAD lacks light-blocking properties, necessitating projection in dark indoor environments. Production of Projectors In addition to NPAD, we aimed to create portable projectors under the following conditions:
3.1. Criteria
Beyond "affordability" and "lightness," we required the projectors to display images across the entire dome surface. This was to differentiate our design from consumer-grade projectors, which are typically designed for single-panel projections and are easier to transport. We thus attempted to create both pinhole and digital planetarium projectors.
3.2. Production
3.2.1. Pinhole Projector A pinhole projector projects images by shining light through small holes in the body onto the dome's surface. Divide the star map into pentagonal sections based on latitude and longitude. Attach these sections to larger pentagonal sheets of drawing paper. Puncture holes at star positions using a pushpin. Assemble these parts into a regular dodecahedron. Insert a small light bulb near the south pole to illuminate from within. 3.2.2. Digital Projector A digital projector uses multiple projectors to display star maps onto the dome's surface. Use a drawing app to edit star maps for curved surfaces, dividing them into five panels (east, west, north, south, and zenith). Construct projectors using cardboard boxes with magnifying glasses and place Chromebooks inside. Set up these projectors at various positions to project images onto the dome.
3.3. Results and Challenges Pinhole Projector: Insufficient light intensity prevented effective projection; solutions include adjusting hole sizes and light bulb brightness. Digital Projector: Successfully projected star maps onto the dome, but issues with visibility of faint stars suggest using more distinct colors. The zenith projection had reduced image size due to distance limitations, indicating a need for further division of the zenith image.
Conclusion We successfully constructed a 4-meter diameter dome capable of projecting planetarium shows and developed portable projectors for use with NPAD.
Future Challenges Enhance NPAD's light-blocking capabilities. Improve projector light sources and refine star color choices for better visibility. Adjust image sizes for zenith projections.
Production of NPAD (News Paper Air Dome)
2.1. Criteria
In constructing the dome, we focused on "affordability" and "lightness," and added the requirement of a "hemispherical" shape. This design choice aligns with how our eyes perceive stars as being at a uniform distance, creating a hemispherical impression of the night sky. Considering these criteria, we decided to create a 4-meter diameter hemispherical air dome made from newspaper, named News Paper Air Dome (NPAD).
2.2. Method Measure a 50 cm diameter globe at every 15° latitude and 10° longitude, recording values to two decimal places (only the polar region is measured at a 6.4° latitude). Multiply the measurements by 8, and create 24 trapezoidal parts and one circular polar region part using newspaper. Assemble these parts using glue sticks and masking tape. Attach 60 cm tall cardboard to the lower half of the dome using masking tape to reduce distortion and prevent light from shining into the audience's eyes.
2.3. Results and Challenges NPAD functioned effectively as a space for projecting stars with minimal distortion. When not in use, it can be reduced to a minimum size of 60 cm and inflated in about 5 minutes using a fan. Challenge: NPAD lacks light-blocking properties, necessitating projection in dark indoor environments. Production of Projectors In addition to NPAD, we aimed to create portable projectors under the following conditions:
3.1. Criteria
Beyond "affordability" and "lightness," we required the projectors to display images across the entire dome surface. This was to differentiate our design from consumer-grade projectors, which are typically designed for single-panel projections and are easier to transport. We thus attempted to create both pinhole and digital planetarium projectors.
3.2. Production
3.2.1. Pinhole Projector A pinhole projector projects images by shining light through small holes in the body onto the dome's surface. Divide the star map into pentagonal sections based on latitude and longitude. Attach these sections to larger pentagonal sheets of drawing paper. Puncture holes at star positions using a pushpin. Assemble these parts into a regular dodecahedron. Insert a small light bulb near the south pole to illuminate from within. 3.2.2. Digital Projector A digital projector uses multiple projectors to display star maps onto the dome's surface. Use a drawing app to edit star maps for curved surfaces, dividing them into five panels (east, west, north, south, and zenith). Construct projectors using cardboard boxes with magnifying glasses and place Chromebooks inside. Set up these projectors at various positions to project images onto the dome.
3.3. Results and Challenges Pinhole Projector: Insufficient light intensity prevented effective projection; solutions include adjusting hole sizes and light bulb brightness. Digital Projector: Successfully projected star maps onto the dome, but issues with visibility of faint stars suggest using more distinct colors. The zenith projection had reduced image size due to distance limitations, indicating a need for further division of the zenith image.
Conclusion We successfully constructed a 4-meter diameter dome capable of projecting planetarium shows and developed portable projectors for use with NPAD.
Future Challenges Enhance NPAD's light-blocking capabilities. Improve projector light sources and refine star color choices for better visibility. Adjust image sizes for zenith projections.