[ErikR]

So the moon has it's phases because of it's Revolution around the earth. The moon is completely lit up when it is directly behind the Earth opposite of the Sun, which makes sense cause the sun is lit it up completely (the earth's shadow on the moon isn't a big factor in how much is lit up). The moon is a new moon when it is between us and the Sun. when it is super perfectly lined up they're called eclipses. The seasons are due to the tilt of the Earth's axis, because of this tilt the hemisphere that's tilted toward the sun (i.e. the sun is directly overhead) heats up more because more light is let in by the atmosphere and therefore heating the ground more.