Why is the full Moon in January this year a Micromoon?
This year's full Moon in January is a "Micromoon."
Consider this word to be the opposite of a "Supermoon."
Simply put, it means that the full Moon is at its farthest distance from Earth. In astronomical terms, this is referred to as the "apogee".
Hence, this full Moon is a Micro Moon (the opposite of a "Supermoon") because it occurs near when the Moon is farthest from the Earth (apogee).
The distance between Earth and the Micro Full Moon this January is specifically about 252,600 miles.
Why is the Moon closer or farther away (in this month) from Earth?Simple Answer
Since the Moon travels an elliptical path around the Earth, so one side is farther away from Earth while the other is nearer.
Although it's probably not that visible to the naked eye, the Moon's size and brightness are affected by its distance.
The perceived size of the Moon from Earth (how big the Moon appears to be from Earth) is more related to the “Moon Illusion” and how near the Moon seems to the horizon.