At certain times of the year, the moon is at its closest point to Earth and these are called supermoons, it's just a natural point of the moon's orbit. At each extreme, the moon is either a little bigger or a little bit smaller( at its furthest point), but it is not a huge difference.

Mike Hankey

Bright moon phases are bad for meteor showers as they wash out the dimmer meteors, a full or almost full moon dominates one part of the sky, making that part undesirable for observing meteors. The full moon also lasts the entire night, leaving no hours of complete darkness, which is preferred.