ROME (AP) — Pope Gregory XIII, the 16th century pontiff responsible for the Gregorian calendar, now has another celestial claim to fame. ROME (AP) — Pope Gregory XIII, the 16th century pontiff ...

We're all Gregorians now. But it took a while. On New Year's Day, just about every corner of the world will flip a calendar in accordance with the system commissioned by Pope Gregory XIII in the 1580s ...

The Vatican Observatory announced this week the naming of four newly discovered asteroids after notable Catholics, including Pope Gregory XIII, who began the tradition of papal astronomers and ...

Thursday, Feb. 29 is leap day — that's something you don't hear very often. Here’s what you need to know about the day that happens almost every four years. 🗓️ What is a leap year? A leap year is ...

ROME -- Pope Gregory XIII, the 16th century pontiff responsible for what is today known as the Gregorian calendar, now has another, celestial claim to fame. A working group of the International ...

This week, two holidays are being celebrated across the country, as the first night of Hanukkah falls on the same day as Christmas. The Jewish celebration of the Festival of Lights begins at sundown ...

We all remember the rhyme from school: "30 days hath September, April, June and November; All the rest have 31 except February alone, which has 28 days clear, and 29 in each leap year." But why do ...

The sun sets behind the dome of St. Peter’s Basilica, in Rome, on Feb. 20, 2023. Pope Gregory XIII, the 16th century pontiff responsible for what is today known as the Gregorian calendar, now has ...