No, cgbg, the primary subject in that picture was the earth, which is illuminated by sunlight. The camera is adjusted to provide detail in the bright area. The region of space that is dark was not the subject, so it was allowed to "black out". This is the very same thing that blacks out the stars in the Apollo pictures taken on the moon. The stars were not the subject, the objects on the moon were. Film, which behaves differently than digital sensors, only has an equivalent exposure latitude if 7 f-stops, or 2
7, or 1:128. The illumination difference between the lunar surface and a star in a dark sky would be 1:4000 or so.
So, it boils down to what the subject happens to be and the range of illumination.
you just explained how someone could hide the background stars if there was something they did not want folks to see Actually, I just explained how someone would show detail on the earth if the stars were not the point of interest. The NASA projects, at least the ones available to the public, are not related to either star or UFO gazing. Please refer to the Hubble project for star gazing.