Monday, December 21, 2026

Monday, December 21, 2026 falls on a Monday. It is day 355 of the year, ISO week 52, in Q4.

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Monday, December 21

December 21, 2026 is day 355 of 365, ISO week 52, in Q4. The moon is Waxing Gibbous and the zodiac sign is Sagittarius.

Day of year355
ISO week52
QuarterQ4
Days left10

Sun and Moon Cycles

Moon phase
Waxing Gibbous
Lunar age
12.1 days
Illumination
92%
Season
Winter in the Northern Hemisphere, summer in the Southern Hemisphere

Zodiac and Holidays

Zodiac
Sagittarius
Observances
No major fixed observance in the built-in calendar
Shareable URL
/date/2026-12-21

Today's Celebrations

December 21
Observance Armed Forces Day (Philippines)
Observance O Oriens
Observance Peter Canisius
Observance Thomas the Apostle
Observance December 21 (Eastern Orthodox liturgics)
Observance Forefathers' Day (Plymouth, Massachusetts)
Observance São Tomé Day (São Tomé and Príncipe)

Daily Briefing

Local brief

Monday, December 21, 2026 combines practical calendar facts with a wider view of the day: 2018: Operatives of the British Special Boat Service boarded the container ship Grande Tema in the Thames Estuary to detain four stowaways who had threatened the crew.. Use it to check the date, plan across time zones, and scan the observances and historical markers attached to December 21.

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History for December 21

10 events

Operatives of the British Special Boat Service boarded the container ship Grande Tema in the Thames Estuary to detain four stowaways who had threatened the crew.

Countries that were part of the Maya civilization celebrated the end-date of a 5,126-year-long cycle in the Mesoamerican Long Count calendar.

In accordance with the Oslo II Accord, Israeli troops withdrew from Bethlehem in preparation for the transfer of control to the Palestinian National Authority.

Mexico's Popocatépetl volcano, dormant for 47 years, began erupting, and is now one of the nation's most active volcanoes.

The world's heaviest aircraft, the Antonov An-225 Mriya, made its first flight.

A bomb on board Pan Am Flight 103 detonated over Lockerbie, Scotland, killing 270 people.

Apollo 8 launched from Kennedy Space Center in Florida on a trajectory to the Moon; its crew (pictured) became the first humans to visit another celestial body.

The United Nations adopted the International Convention on the Elimination of All Forms of Racial Discrimination, which 88 member states have since signed.

News of the day

Wikimedia Current Events

No current-events archive was available for this date during generation.