The model Saturn together with four of its moons at the one to 10-billion scale. The model Saturn has an equatorial diameter of 1.21 cm (0.48 inches) and a polar diameter of 1.10 cm (0.43 inches). It is obvious when looking in the glass that the planet is noticeably ‘oblate’. Saturn’s A, B, C, and D rings are also depicted to scale.

Saturn has five moons that have diameters greater than 1,000 km, which was the size cutoff for representation within the Voyage exhibition. Four of them, Tethys, Dione, Rhea, and Titan, are located in the glass at their scaled orbital distances from Saturn. The moon Iapetus, with a diameter of 1,436 km, is the only moon larger than 1,000 km that is not depicted in the Voyage exhibition. Iapetus is so far from Saturn that it could not be located inside the glass.

Titan is the second largest moon in the Solar System, and bigger than Mercury. Its true diameter of 5,150 km (3,190 miles) translates into a model diameter of 0.5 mm (0.02 inches).

Credit: ©Smithsonian Institution, Eric Long