Note the "roaring lion" on the upper right, facing down at the center. It is somewhat displaced and distorted between the two images. My overlay is only scaled and rotated. The overlay rectangle is the entire March 2013 APOD.
It appears to me that some of the stars in front of the "lion" are in a pattern greatly reduced in size for January 2015 ... evidence to me of some very artful processing.
More times than not, NASA does some “image processing” which they don’t always announce beforehand, especially when working with wavelengths other than visible. In this case an “illusory-color four-panel mosaic”. But aside from composites, color enhancement, false colorization, etc, I’ve never heard of a case where they’ve actually altered anything. Of course those claiming they’re covering up evidence of aliens on the moon and Mars disagree.