Though Hubble’s images can showcase amazing celestial wonders, they do distort the universe in an obvious and important way. The vastness of space is compressed down to a flat, two-dimensional picture. Nearby stars and distant galaxies, billions of light-years apart, may appear to sit side-by-side. To the public, astronomical observations offer few clues as to how to interpret the distances to objects.
For a few Hubble press releases, our scientific visualization group provides a reminder of the three-dimensional nature of the imagery with a virtual journey across space. The most recent is an exploration of a star-forming region known as S106. The movie takes the viewer past the foreground stars and descends toward the gaseous landscape of the nebula.
When creating the 3D models for these visualizations, we utilize scientific knowledge where available. In the case of S106, a couple of research papers outlined the hourglass shape of the nebula, as well as the directions of the central outflows. Other aspects required using scientific intuition, such as the statistical model used to place stars in front of and behind the nebula. When neither knowledge nor intuition is available, we use artistic license to fill out details, while diligently striving to remain scientifically plausible.
Folks are sometimes surprised when I tell them that our goal is not strict scientific accuracy. The main problem is that the universe is incredibly big and sparsely populated. Distances usually must be significantly compressed to create more engaging visualizations. In other situations, the scales in length, time, temperature, density, etc., can be, well, astronomical. Our goal for these visualizations is not textbook instruction, but to remind people of the 3D structure inherent within the Hubble imagery.
Experience has shown that these visuals can have a powerful effect. How we imagine the universe plays a strong role in how we interpret and understand new information about astronomy. These visualizations not only explore celestial wonders, but also help set one’s “mental model” of the cosmos. All it takes is looking from a different perspective.