March 28

German astronomer Heinrich Olbers discovers the asteroid Pallas, the second asteroid ever found.

German astronomer Heinrich Wilhelm Olbers, an amateur observer who also discovered several comets, identified Pallas, the second asteroid ever found after Ceres the previous year. Both objects were initially classified as new planets before astronomers gradually recognized, as more similar bodies were discovered, that they belonged to a much larger population of minor planets orbiting between Mars and Jupiter.

Britain and France declare war on Russia, entering the Crimean War.

Britain and France formally declared war on Russia in response to Russian expansion into Ottoman territories, entering the Crimean War in support of the Ottoman Empire. The brutal conflict, notable for the logistical failures exposed by war correspondents, later prompted major military and medical reforms.

The Paris Commune formally establishes its governing council after the March 18 uprising.

Following the earlier armed uprising in Paris, the Commune's governing council was formally installed after an election, establishing a radical municipal government that pursued socialist and secular reforms before being crushed by French national forces in the "Bloody Week" that May.

The Turkish cities of Constantinople and Angora are officially renamed Istanbul and Ankara.

As part of sweeping modernization and secularization reforms pursued by Mustafa Kemal Ataturk, Turkey's government officially adopted the names Istanbul and Ankara for the cities long known internationally as Constantinople and Angora, requiring foreign postal services to use the updated names. The change was part of a broader effort to forge a distinct, modern Turkish national identity.

Madrid falls to Nationalist forces under Francisco Franco, effectively ending the Spanish Civil War.

Nationalist forces under General Francisco Franco entered Madrid unopposed after the city's remaining Republican defenders, exhausted and divided by internal factional fighting, surrendered without further resistance. The fall of the capital effectively ended the nearly three-year Spanish Civil War, and Franco went on to rule Spain as an authoritarian dictator for the next thirty-six years.

British and Australian forces defeat the Italian navy at the Battle of Cape Matapan in the Mediterranean.

In one of the few major Allied naval victories in the Mediterranean theater during World War II's early years, British and Australian warships decisively defeated the Italian fleet near the Greek coast at the Battle of Cape Matapan, sinking several cruisers and destroyers.

A partial meltdown occurs at the Three Mile Island nuclear power plant in Pennsylvania, the worst nuclear accident in U.S. history.

A combination of mechanical failure and operator error caused a partial meltdown of a reactor core at the Three Mile Island nuclear plant near Harrisburg, Pennsylvania, releasing small amounts of radioactive gas. The accident became the worst commercial nuclear incident in U.S. history and reshaped public attitudes toward nuclear power.

Nelson Mandela is elected deputy president of the African National Congress.

Nelson Mandela, having been released from prison the previous year after 27 years of incarceration, was elected deputy president of the African National Congress, positioning him as the organization's leading figure ahead of South Africa's transition to democratic, multiracial elections.

A magnitude 8.6 earthquake strikes off the coast of Sumatra, Indonesia, killing over a thousand people.

A powerful undersea earthquake struck off the coast of Sumatra, Indonesia, killing over a thousand people and triggering fears of another major tsunami following the catastrophic Indian Ocean tsunami just three months earlier, though the resulting waves proved less devastating.

The Chelyabinsk-sized asteroid 2014 FR is discovered, part of ongoing efforts to track near-Earth objects.

Astronomers cataloged the small near-Earth asteroid 2014 FR as part of ongoing international survey efforts to identify and track potentially hazardous objects whose orbits bring them close to our planet. Such cataloging work, using ground-based telescopes and automated detection systems, reflects the growing global emphasis on planetary defense following several high-profile close approaches and impact events in preceding years.