Perigee Full Moon 20th March 2011

We’ve all heard so much about the biggest and closest moon this weekend but what does this really mean?

The 2011 full moon in March is on the same day as perigee which is the moon’s closest point to Earth for this month. The Moon’s orbit is elliptical and not circular so perigee and apogee (furthest away) happens every month but this perigee happens to be one of the closest encounters and the Moon won’t come this close again until 14th November 2016.

Most people know that the Moon is responsible for the tides in the seas and oceans and full moons bring higher (and lower) than usual tides. This is because the Moon and the Sun are lined up on opposite sides of the Earth so the gravitational pull on the large bodies of water is the greatest. Perigee full moons can bring even slightly higher and lower tides.

So this “Super Moon” isn’t really bigger although it may appear slightly larger in the sky (14% bigger) particularly when rising and setting on the horizon and it certainly isn’t responsible for any earthquakes.