For students with visual impairment, the volume of sound can be used to represent the brightness of stars as the concepts of apparent and absolute magnitude.
This hands-on activity allows students who are blind or visually impaired to "build" a model of the solar system showing relative distances between planets.
In this activity, students consider how a model of the 3-D Earth can be shown in 2-D on a tactile graphic, and why models, though useful, have limitations.