While calculations of days, months and years are based on fixed hours equal to 1/24 of a day, the beginning of each halachic day is based on the local time of sunset.
Mentres que o cálculo dos días, meses e anos estaba baseado en horas fixas iguais a 1/24 dun día, o comezo de cada día ghalaquic estaba baseado na hora local do solpor.