Spiral galaxies are pancake-shaped collections of billions of stars, along with vast clouds of gas and dust. This video illustrates how their observed shapes can differ greatly depending upon the angle at which they are observed. The spiral galaxies NGC 4302 (left) and NGC 4298 (right) are visualized in three dimensions and rotated to showcase how they might look if viewed from other perspectives. Each galaxy could be seen as a roughly circular face-on spiral, as a long, thin, edge-on spiral, or as any of the oblong shapes in between.
The galaxy models are based on observations by the Hubble and Spitzer space telescopes, as well as on the statistical properties of galaxies. Because NGC 4302 is seen nearly edge on, and its structure is not well-defined, its model was based upon observations of the spiral galaxy Messier 51.
NASA, ESA, F. Summers, J. DePasquale, Z. Levay, and G. Bacon (STScI)
Publication: April 20, 2017