What happened 15 January

Tycho and others had observed the supernova of 1572. Ottavio Brenzoni's letter of 15 January 1605 to Galileo brought the 1572 supernova and the less bright nova of 1601 to Galileo's notice. Galileo observed and discussed Kepler's supernova in 1604. Since these new stars displayed no detectable diurnal parallax, Galileo concluded that they were distant stars, and, therefore, disproved the Aristotelian belief in the immutability of the heavens.

The decisive French triumph at Rivoli in January 1797 led to the collapse of the Austrian position in Italy. At Rivoli, the Austrians lost up to 14,000 men while the French lost about 5,000.

The Stravinsky family returned to Switzerland (as usual) in the fall of 1913. On 15 January 1914, a fourth child, Marie Milène (or Maria Milena), was born in Lausanne. After her delivery, Katya was discovered to have tuberculosis and was confined to the sanatorium at Leysin, high in the Alps. Igor and the family took up residence nearby.

King was born on January 15, 1929, in Atlanta, Georgia, to the Reverend Martin Luther King Sr. and Alberta Williams King.

Tarragona fell on 15 January.

On 15 January 1943, Hitler appointed Goebbels as head of the newly created Air Raid Damage committee, which meant Goebbels was nominally in charge of nationwide civil air defenses and shelters as well as the assessment and repair of damaged buildings.

Stravinsky's unconventional dominant seventh chord in his arrangement of the "Star-Spangled Banner" led to an incident with the Boston police on 15 January 1944, and he was warned that the authorities could impose a $100 fine upon any "re-arrangement of the national anthem in whole or in part". The police, as it turned out, were wrong. The law in question merely forbade using the national anthem "as dance music, as an exit march, or as a part of a medley of any kind", but the incident soon established itself as a myth, in which Stravinsky was supposedly arrested, held in custody for several nights, and photographed for police records.

In the early hours of January 15, 1978—one week after his arrival in Tallahassee—Bundy entered FSU's Chi Omega sorority house through a rear door with a faulty locking mechanism.

Beginning at about 2:45 a.m. Bundy bludgeoned Margaret Bowman, 21, with a piece of oak firewood as she slept, then garroted her with a nylon stocking.

Ted then entered the bedroom of 20-year-old Lisa Levy and beat her unconscious, strangled her, tore one of her nipples, bit deeply into her left buttock, and sexually assaulted her with a hair mist bottle.

In an adjoining bedroom Ted attacked Kathy Kleiner, breaking her jaw and deeply lacerating her shoulder; and Karen Chandler, who suffered a concussion, broken jaw, loss of teeth, and a crushed finger. Chandler and Kleiner survived the attack; Kleiner later attributed their survival to automobile headlights illuminating the interior of their room and frightening away the attacker.

Tallahassee detectives later determined that the four attacks took place in a total of fewer than 15 minutes, within earshot of more than 30 witnesses who heard nothing. After leaving the sorority house, Bundy broke into a basement apartment eight blocks away and attacked FSU student Cheryl Thomas, dislocating her shoulder and fracturing her jaw and skull in five places. She was left with permanent deafness and equilibrium damage that ended her dance career. On Thomas' bed, police found a semen stain and a pantyhose "mask" containing two hairs "similar to Bundy's in class and characteristic".

Khomeini was not allowed to return to Iran during the Shah's reign (as he had been in exile). On 16 January 1979, the Shah left the country (ostensibly "on vacation"), never to return.

For Slovenia, the war marked the decisive defense of its independence in regard to Yugoslavia. It was officially recognised by all European Community member states on 15 January 1992.

This so-called Sarajevo Agreement became a lasting ceasefire. Croatia was officially recognized by the European Community on January 15, 1992.

As the UNTAES replaced the UNCRO mission, Prevlaka peninsula, previously under UNCRO control, was put under control of United Nations Mission of Observers in Prevlaka (UNMOP). The UNMOP was established by United Nations Security Council Resolution 1038 of 15 January 1996, and terminated on 15 December 2002.

The new UN mission was established as the United Nations Transitional Authority for Eastern Slavonia, Baranja and Western Sirmium (UNTAES) by United Nations Security Council Resolution 1037 of 15 January 1996.

The transitional period was subsequently extended by a year. On 15 January 1998, the UNTAES mandate ended and Croatia regained full control of the area.

On 15 January 1999 the Račak Killings occurred when "45 Kosovan Albanian farmers were rounded up, led up a hill and massacred".

On 15 January 2009, the South Korean news agency reported that Kim Jong-il had appointed Kim Jong-un to be his successor.

Sullenberger asked controllers for landing options in New Jersey, mentioning Teterboro Airport. Permission was given for Teterboro's Runway 1, Sullenberger initially responded "Yes", but then: "We can't do it ... We're gonna be in the Hudson". The aircraft passed less than 900 feet (270 m) above the George Washington Bridge. Sullenberger commanded over the cabin address system, "Brace for impact", and the flight attendants relayed the command to passengers. Meanwhile, air traffic controllers asked the Coast Guard to caution vessels in the Hudson and ask them to prepare to assist with the rescue.

Sullenberger opened the cockpit door and gave the order to evacuate. The crew began evacuating the passengers through the four overwing window exits and into an inflatable slide/raft deployed from the front right passenger door (the front left slide failed to operate, so the manual inflation handle was pulled). A panicked passenger opened a rear door, which a flight attendant was unable to reseal. Water was also entering through a hole in the fuselage and through cargo doors that had come open, so as the water rose the attendant urged passengers to move forward by climbing over seats. One passenger was in a wheelchair. Finally, Sullenberger walked the cabin twice to confirm it was empty.

After winning his first three matches in charge of the national team, he oversaw a 6–1 defeat to Bolivia, equalling the team's worst-ever margin of defeat. With two matches remaining in the qualification tournament for the 2010 World Cup, Argentina was in fifth place and faced the possibility of failing to qualify, but victory in the last two matches secured qualification for the finals. After Argentina's qualification, Maradona used abusive language at the live post-game press conference, telling members of the media to "suck it and keep on sucking it". FIFA responded with a two-month ban on all footballing activity, which expired on 15 January 2010, and a CHF 25,000 fine, with a warning as to his future conduct.

On January 15, 2013, Facebook announced Facebook Graph Search, which provides users with a "precise answer", rather than a link to an answer by leveraging data present on its site.

On 15 January 2019, May's government was defeated in the House of Commons by a margin of 230 votes (202 in favour and 432 opposed) in a vote on her deal to leave the European Union. It was the largest majority against a United Kingdom government in history.

On 15 January 2019, the House of Commons voted 432 to 202 against the deal, which was the largest majority against a United Kingdom government ever.

A Netflix documentary entitled Killer Inside: The Mind of Aaron Hernandez was released for streaming on January 15, 2020.