Their mission takes them on explorations through measurements of colors for thousands of celestial objects. To find a primeval galaxy, it is necessary to search for the most distant galaxies in the universe. The more distant a galaxy, the longer its light has taken to reach us, and the farther back in time we see it.
More distant galaxies are fainter.
But there are nearby galaxies which are faint, too. To identify a faint galaxy as being distant, it is necessary to search for a special color signature which distinguishes it from objects which are nearby. McCall and De Robertis hypothesized that the first galaxies should emit certain colors of light less strongly than nearer galaxies. Using Data Desk, they were able pinpoint 8 primeval galaxy candidates. However, to definitively prove whether or not the candidates are indeed primeval, it will be necessary to acquire measurements of how fast they are moving away from us as a consequence of the expansion of the universe.