For all of our models we start with astronomical data take from the Sloan Digital Sky Survey. These data are transformed from their original file format (
.fits) into something a bit more user friendly (
.png). During this conversion process we also apply a “stretch” to the data so the faintest features (e.g. spiral arms) and the brightest features (e.g. the center) of the galaxy are easily visible at the same time.
This results in a black-and-white image of the galaxy representing all the light of a particular color coming from the galaxy. To make our 3D model this image is used as a height map with white being the most raised point and black being the least raised point. A border with a height equal to the highest point on the model is added around the outside to act as a point of reference when feeling the models. This process has been automated with a custom plugin available we have made available on github.
After the model is crated it is exported as an
.stl file and prepared for 3D printing. This process will be explored in more depth in our next post.