Color images of distant, faint galaxies interesting to astronomers because the color enables them to estimate the redshift, a key astrophysical parameter in understanding how galaxies are organized in the Universe. Recently, Jiangang Hao and Jim Annis of Fermilab co-added 3 million full-color images from the Sloan Digital Sky Survey, using an image stacking and averaging process commonly used by astronomers to improve the quality of their images. The figure below shows the impact of this co-adding technique.
Then they converted the images to a file format that can be uploaded and visualized in the Google Sky tool, which can be used to pan and zoom across the sky. You can see this in action in the animation below.
Hao and Annis’ images are in fact much sharper than those ordinarily accessible in Google Sky, which has generally degraded images to reduce load times.
Read about how Hao and Annis produced these files for consumption by Google Sky.