[asmithmd1]

Uh, no. The ONLY time we see a new moon is during an eclipse. Other times the moon is above or below the sun and is too dim to see. A lunar eclipse is when the moon passes into the earth’s shadow and they happens during full moons

[nine_k]

OK, we don't actually get to recognize the shape of the new moon with a naked eye because it's dark against the sky. It's still hot enough for some time to be visible in IR pretty well.

The point is that the lit part of the Moon moves widely, while the far / near sides don't due to the tidal lock. Hence they can't be used interchangeably.

[philwelch]

I think if you’re somewhere free of light pollution you might notice a moon-sized gap in the stars.