NAMES OF THE DAYS IN A WEEK

A week consists of 7 days, and each day 24 hours.
Each two hours are dedicated consecutively to one of the celestial bodies according to the following order:
Saturn, Jupiter, Mars, Sol, Venus, Mercurius, Luna.
If the day starts with Saturn, the 25th and 26th hours (the next day) will be dedicated to Sol.
If the day starts with Sol, the 25th and 26th hours (the next day) will be dedicated to Luna and so on.
The names of the days in a week are therefore established in such order.

Dies Solis. Sunday. Sun's day.

Dies Lunae. Monday. Moon's day. (Lunedi, Lundi in Italian and French)

Dies Martis. Tuesday. Tiws day. (Martedi, Mardi in Italian and French)

Dies Mercurii. Wednesday. Wodens day. (Mercoledi, Mercredi in Italian and French)

Dies Jovis. Thursday. Thors day. (Giovedi, Jeudi in Italian and French)

Dies Veneris. Friday. Friggs day. (Venerdi, Vendredi in Italian and French)

Dies Saturni. Saturday. Saturn's day.


DAYS IN THE MONTHS OF THE YEAR

By the order of Julius Caesar all odd months have 31 days and even months 30 days except February which has 28 or 29 days.

Later, following the example of Julius who renamed Septilis (the seventh month) into July, Augustus renamed Sextilis (the sixth month) into August as well as making it 31 days, although it is an even month.
And to avoid having three months with 31 days consecutively, he changed all odd months after August into 30 days and all even months into 31 days.