Explaining the Scale of the Solar System Using the Thousand Yard Model

June 07, 2015

Bowling ball sun

Photographer: Matthew Stewart
Summary Author: Kevin Stewart 

I'd like to make visitors to the Earth Science Picture of the Day as well as similar sites aware of the very accessible and accurate Thousand Yard Model of the Solar System developed by Guy Ottewell. Last year, we had the pleasure of adapting it for the Boy Scout STEM Camporee in the Lancaster-Lebanon Council in Pennsylvania. The route was folded into Lancaster’s Long’s Park and included a stop for the asteroids, featuring a very tiny dot on a card to show Ceres. Since I repeated the hike for a number of groups, I kept the "planets" with me but had planet images and descriptions at the appropriate stops.
My brother, Matthew, constructed the Sun-holder pictured here. For those who want to build their own optional sun-holder, see the link below for details on how to make it. This construction not only had the advantage of drawing folks’ attention to the display, but provided the additional benefits of making the Sun (a 9 pound, yellow bowling ball) less likely to wander off when it was out of sight, and of making it still detectable to the naked eye when we were quite some distance from it—just barely visible when we were out by Saturn.
EarthMoon_juno_2011238Some of the best moments were when younger participants came to the realization and understood that that piece of a poppy seed 2.4 inches (6.1 cm) from the 0.08 in (2 mm) peppercorn Earth was the Moon. I recall the excitement of a young Scout when he discovered on his own and was able to appreciate just how much smaller the Sun appeared when we had got as far as Jupiter, 405 ft (123 m) away, and turned around to look back. The image at left shows Earth and Moon as observed by the Juno spacecraft some 6 million mi (10 million km) from Earth -- provided by NASA/JPL-Caltech.
I’ve found that the Thousand Yard Model of the Solar System is a fun activity to share with young and old and is a wonderful way to spur interest in astronomy since it simply explains the scale and size of our solar system.
Photo Details: Top - Camera Maker: Motorola; Camera Model: DROID RAZR; Focal Length: 4.6mm; Digital Zoom: 1.000x; Aperture: ƒ/2.4; Exposure Time: 0.0018 s (1/563); ISO equiv: 100; Software: Paint.NET v3.5.11.