The second closest full supermoon will reach its peak tonight. It is known as the Worm Moon due to its connection to the changing season.

The Worm Moon started to appear on Sunday but will become fully visible tonight. The full supermoon is expected to extend until Wednesday.

How do Supermoons occur?

Supermoons occur when the Moon reaches its closest distance to Earth, which is known as the perigee. This arises due to the Moon's oval orbit around Earth. Since the natural satellite does not follow a perfectly circular path around the planet, it occasionally moves closer and farther away from Earth as it completes its orbit.

supermoon
A full moon rises behind blocks of flats in north London, Britain, January 31, 2018. Reuters

This week, the Moon will appear to be about 14 percent larger and 30 percent brighter as it reaches its perigee. During this time, the Moon will be about 222,081 miles from the planet. This means it will be about 16,000 miles closer to Earth than usual, iNews reported.

Meaning of Worm Moon's name

The current supermoon is referred to as the Worm Moon due to the traditions of the Native American culture. It was named as such because, during this time of the year, the weather changes from cold to warm, causing the soil to thaw. As this happens, earthworm casts become visible on the ground, prompting birds to return in order to feed.

The Worm Moon usually appears as the last full moon before the end of the winter equinox. This is a period when the weather is colder and the dark or night times are longer.

Super Moon
A lunar eclipse of a full "Blue Moon" is seen above the ferris wheel on the Santa Monica Pier in Santa Monica, California, U.S., January 31, 2018. Reuters

Seeing the Worm Moon and other supermoons

This week's full supermoon will be visible from anywhere in the world. In North and South America, the Worm Moon's appearance will begin during the daylight hours of March 9. It will reach its peak fullness around the afternoon and will be visible throughout the evening.

Following the Worm Moon, two other supermoons will reach their peak fullness this year. The first will happen on April 8 while the second supermoon will appear on May 7. The supermoon happening in April will be closer to Earth than the Worm Moon. According to EarthSky, next month's supermoon will be about 221,851 miles from the planet.