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Year: the time that it takes the Earth to make one orbit of the sun. The tropical year is the interval in which the mean ecliptic longitude of the Sun increases by 360º. This is the version of the year used in normal calendars and has a length of 365.24219 days. Other versions of a year (e.g. the sidereal, anomalistic and Julian years) have differences of about a hundredth of a day to this figure.
Yule: an ancient Celtic festival held on or around the 21st of December, celebrating the winter solstice. It is
one of the cross-quarter days, and has now become synonymous with Christmas.