The Supermoon is Coming Again

The supermoon is coming. But fear not, it's just the moon, but it'll look a little bigger.
At 7am ET on Sunday, the moon will hit the point in its orbit that's closest to us (ie, reaching "perigee"). At 7:32am ET, the moon will officially be full.

The convergence of these events gives us the largest full moon of 2013.

While that's all cool and dandy, you probably won't be able to tell that the moon is much bigger, because it won't be much bigger than it was last month, just bigger than it is at apogee.

If you're wondering if this will affect tides, the answer is yes. Space.com breaks down the math:

At perigee on Sunday, the moon will be 221,824 miles from Earth, which is about 12.2% closer than when the moon is farthest from us (at apogee). "Tidal force varies as the inverse cube of an object's distance." With that 12.2% figure in mind, that means the supermoon "will exert 42% more tidal force at this full moon compared to the spring tides for the full moon that will coincide with apogee next January."