an eclipse not an ellipse
If the Moon is between Earth and the Sun, it is not a phase, at all . . . it is a solar eclipse.
The phase of the moon depends on it position in relation to the earth and the sun. For instance, when the moon is in between the earth and the sun, this is the new of full moon phase.
full moon
New moon.
new moon
New moon.
New moon.
New moon.
New moon.
Full Moon
A new moon.
That's 'New Moon'.