Equinox is taken from the Latin meaning "equal night" and marks the time of year, in Spring and Autumn, when the days and nights are of equal length. It signals a time of changing seasons; a move from the long, warm days of the summer into the shorter, cooler days of autumn.
The Ancient Celts would traditionally have marked this occasion with festivities to give thanks for the harvests gathered in during the summer and to prepare and stock up for the colder months ahead.
Monuments were also build around Ireland that have been linked to the spring and autumn equinox. Dating back to 3000 BC, Loughcrew in County Meath consists of passage tombs that are aligned to become illuminated by the sun at these significant times of year.
This year the autumn equinox falls on 23rd September.