Science quiz: A millennia-old calendar system

1 / 6 |
Identify this Roman deity associated with gates and transitions, and identified as the tutelary deity of January.

2 / 6 |
While the Julian calendar included a leap day once every four years, it was not the first calender to have such a system. For example, the Roman system that it replaced included a month called X once every two or three years. What is X? In Latin it means ‘work month’.

3 / 6 |
Julius Caesar, who instituted the Julian calendar by a decree on January 1 of 45 BC, consulted the Alexandrian astronomer _________ when reforming the Roman calendar in order to base the new calendar on the solar year rather than on the variable lunar Roman system. Fill in the blank.

4 / 6 |
Which specific astronomical cycle was the Julian calendar attempting to approximate? This was so that calendar dates would stay aligned with the seasons instead of drifting through the year, thus also keeping the sun’s equinoxes and solstices on the same dates.

5 / 6 |
In 46 BC, the Julian calendar reform realigned the Roman calendar with the seasons in 46 BC by creating a “____ __ _________”. This transitory period was effectively a 445-day long civil year that included two extraordinary months between November and December. Fill in the blanks.

6 / 6 |
What is the difference in the length of the average year between the Julian and the Gregorian calendars (in number of days)? Pope Gregory XIII instituted the Gregorian calendar in 1582, via the papal bull ‘Inter gravissimas’.