Today at 2:10 pm EST the biggest full moon since 1983 will rise from the eastern horizon. The moon will appear large because it’s reaching its perigree, the closest approach to earth in its orbit. According to NASA, perigree moons are 14% bigger and 30% brighter than moons on the apogee side of the moon’s orbit, when it is farthest away from earth. What’s special about Saturday’s perigree moon is that it’s almost coinciding with a full moon, a relatively rare occurrence. Some refer to this coincidence as a supermoon.