* Moon's Orbit: The moon orbits the Earth in a counterclockwise direction when viewed from above the North Pole.

* New Moon: At the new moon phase, the moon is between the Earth and the Sun, and we don't see it (since the sunlit side faces away from us).

* Moving Eastward: As the moon orbits eastward, it moves away from the sun's position in the sky.

* 90-Degree Angle: When the moon has moved about 90 degrees in its orbit from the new moon position, it forms a right angle with the Earth and the Sun.

* Half-Illuminated: From our perspective, the sun illuminates half of the moon's surface, creating the "half-bright, half-dark" appearance.

Let me know if you'd like to know more about moon phases!