Just a few hours remain until the magical sight of October’s supermoon. This is the first supermoon of the year, also known as the “Harvest Moon.”

Tonight’s moon is expected to be the largest and brightest of 2025, as the Moon will reach the closest point in its orbit around Earth.

According to the Almanac, the “Harvest Moon” is the full moon that occurs closest to the September equinox, which this year fell on September 22.

The nickname comes from rural tradition, where the moonlight was said to help farmers continue harvesting late into the evening, not just on the night of the full moon, but also on the nights surrounding it.

Although the “Harvest Moon” often occurs in September, the lunar calendar has designated October as the month of the Harvest Moon for 2025.

What is a Supermoon?

The Moon’s orbit around Earth is elliptical, meaning its distance from Earth varies throughout the year. When a full moon occurs at or near its closest point to Earth — called the perigee — and within 90% of that closest distance, it is known as a supermoon.

If the full moon happens when the Moon is at its perigee, or within 90% of that distance, it is considered a supermoon.

The term was first coined in 1979 by astrologer Richard Nolle, to describe full moons that appear noticeably larger and brighter, as they coincide with perigee.

Supermoons can appear up to 14% larger and 30% brighter than other full moons, when viewed from Earth.

Different members of the astronomical community have adopted slightly different definitions of what constitutes a supermoon. One alternative definition includes any full moon that comes within 360,000 km of the Earth’s center — and by this definition, the October Harvest Moon would not qualify as a supermoon.