If we wanted to do something cool in space just for the fun of it...
This would be doable and would be something everyone remembered for a long time.
Most of our visual information about volume comes from reflected light, labeled D in these pictures. Direct and reflected light offer illumination from two different angles, giving us a rich sense of form and volume.
The moon appears flat because all the light is stark sunlight and there is nothing on the other side of the moon for that sunlight to bounce off of, so the darkened part of the moon is just dark.
Sometimes there is enough reflected light from Earth that we see the darkened part of the moon as dark gray, but it still doesn't look three dimensional because the reflected light is from Earth and we are on Earth... the light comes from where we are so it doesn't offer an angled perspective. The reflected earthlight illuminates the face of the moon evenly, from our perspective, and thus doesn't add volume information. (In the way flash photography tends to make things look flat because the light is coming from the same place as the lens... and why photographers sometimes have the flash mounted on a rod extending a foot from the camera to add a little apparent volume in the shadows.)
We do get a little sense of three-dimensionality from the terminator...
Sorry, wrong terminator...
...from the terminator, the area on the edge of the lighted part. ("C" in those drawings of shapes.) Those craters look 3-D, but the overall moon does not.
But if a light source sideways to the moon (from our perspective) threw a little light into the darkened part it would suddenly look like an honest-to-goodness ball in the sky.
A nearby super nova might offer such a sideways light source. (It might also sterilize our planet, though.)
But if we don't want to wait for a super nova, we could make the moon look 3-D ourselves. Maybe just the flash of an explosion off in space, or maybe something longer lasting like a huge reflective sail orbiting the moon.
Either way, it would be plenty cool.
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