The lunar phases describe the form we perceive the moon having based on the light it reflects from the sun while being partially turned away from us.
Q: Can we abuse science to make the moon have physical phases?
By having physical phases I mean that the physical shape of the moon changes in cyclic manner. Thus if one would land on the moon, in its crescent the moon would be an actual crescent opposed to just appearing as one due to what we see reflected.
We can do the following things:
We can not do these things though:
- change the mass of the moon