The full moon on March 20 will be the third and final supermoon of 2019.
A supermoon is a full moon that occurs when the moon is at the closest point in its orbit to Earth.
Supermoons may appear bigger and brighter than ordinary full moons, especially as the moon rises and sets. Scientists say this is an illusion that occurs because there are other objects, like trees or buildings, in our line of sight and our brain is tricked into thinking the moon is closer to those objects than it really is.
The first supermoon of the year was on Jan. 21. The second was on Feb. 19.
In folklore, March’s full moon is known as the “worm moon” because this is typically the time of year when earthworms begin to appear in the soil again as the ground thaws out. Some are calling this the “super worm moon.”
It also happens to coincide with the beginning of spring or the vernal equinox. The spring and fall equinoxes occur when the sun is directly over the equator, giving us the same number of daylight hours as darkness. As spring continues, the number of daylight hours will continue to increase until the summer solstice on June 21.
According to EarthSky.org, this is the first time since March 2000 that the full moon and the spring equinox have occurred so closely together. The next time this will happen will be March 2030.