By definition, a supermoon is simply a full moon that happens to be close to the earth.  

On March 19, the supermoon will be one of “rare size and beauty,” said NASA’s website.

How rare is it?

The last full Moon so big and close to Earth occurred in March of 1993, said Geoff Chester of the US Navy.

The moon’s orbit around the earth is oval; therefore, sometimes it’s close to the earth and sometimes it’s farther away.

The distance between the farthest point (apogee) and the nearest point (perigee) is about 50,000 km.  The perigee moons are 14 percent bigger and 30 percent brighter than apogee moons.

On March 19, the moon will be less than one hour away from the perigee, according to Chester, so it’s near “perfect.”

What’s the best time to view this beautiful moon?

According to NASA, “the best time to look is when the Moon is near the horizon…That is when illusion mixes with reality to produce a truly stunning view.”

Lastly, NASA stated that contrary to rumors floating on the Internet, supermoons don’t cause natural disasters and the current approaching one was not responsible for Japan’s tragedy.