25 December 839

After the loss of aircraft systems, Azerbaijan Airlines Flight 8243 crashed near Aktau International Airport while attempting to perform an emergency landing after being hit by a Russian defense missile.

A Tupolev Tu-154 of the Russian Defence Ministry crashed into the Black Sea shortly after taking off from Sochi International Airport, killing all 92 people on board.

Aboard Northwest Airlines Flight 253, Umar Farouk Abdulmutallab attempted to detonate plastic explosives hidden in his underwear.

A fire destroyed Longford's 19th-century St Mel's Cathedral, considered the "flagship cathedral" of the Irish midlands.

A tiger at the San Francisco Zoo escaped from its enclosure and attacked three patrons before it was shot and killed.

Russian president Vladimir Putin signed into law a bill officially adopting a new national anthem, with music by Alexander Vasilyevich Alexandrov originally composed for the anthem of the Soviet Union.

In a nationally televised speech, Mikhail Gorbachev resigned as President of the Soviet Union.

British computer programmer Tim Berners-Lee introduced WorldWideWeb, the world's first web browser and WYSIWYG HTML editor.

Romanian Revolution: Communist dictator Nicolae Ceaușescu and his wife Elena were condemned to death on a wide range of charges and executed.

In Tamil Nadu, India, families of striking Dalit workers were massacred by a gang, allegedly led by their landlords.

Second World War: The Japanese occupation of Hong Kong began when Mark Aitchison Young, the Governor of Hong Kong, surrendered the territory to Japan after 18 days of fierce fighting.

The Việt Nam Quốc Dân Đảng, a revolutionary socialist political party that sought Vietnamese independence from French colonial rule, was formed in Hanoi.

American physician Ephraim McDowell performed the world's first removal of an ovarian tumor.

Based on predictions by Edmond Halley in 1705, Johann Georg Palitzsch observed a comet that was later named Halley's Comet .

J. S. Bach led the first performance of the Christmas cantata Unser Mund sei voll Lachens, BWV 110, making laughter audible in singing.

Johann Sebastian Bach led the first performance of Gelobet seist du, Jesu Christ, based on the Christmas hymn written by Martin Luther in 1524.

Baldwin I was crowned the first king of Jerusalem (depicted) in the Church of the Nativity in Bethlehem.

Norman Conquest: William the Conqueror was crowned King of England at Westminster Abbey, but continued to face rebellions over the following years and was not secure on the throne until after 1072.

Henry III was crowned Holy Roman Emperor by Pope Clement II.

After the death of Emperor Gongsun Shu of Chengjia, the empire was conquered by the Eastern Han dynasty.

Azerbaijan Airlines Flight 8243 crashes in Aktau, Kazakhstan, killing 38 of its occupants.

The James Webb Space Telescope is launched.

An explosion in Nashville, Tennessee, occurs, leaving three civilians in the hospital.

Twenty people are killed and thousands are left homeless by Typhoon Phanfone in the Philippines.