2003

January

 * – Illinois Governor commutes the death sentences of 167 prisoners on Illinois's death row based on the  scandal.
 * – The last signal from NASA's  spacecraft is received, some 12.2 billion kilometers (7.6 billion mi) from.
 * –, becoming the second country in the world to do so.

February

 * – At the conclusion of the  mission, the over, killing all seven astronauts on board.
 * – The is renamed to the "State Union of Serbia and Montenegro" (or "Serbia and Montenegro" for short) as its leaders reconstitute the country into a loose state-union between  and, marking an end to the 73-year-long use of the name "Yugoslavia" by a sovereign state.
 * – – : An Italian gang steals loose diamonds, gold and jewellery valued at more than $100 million from a Belgian vault, one of the largest robberies in history.
 * – Millions of people worldwide take part in massive in anticipation of the United States and its allies invading.
 * – An arsonist in Daegu, South Korea, killing 192 people.
 * - occurs in, killing 100 people and injuring 230 and another 132 escape uninjured.
 * – The begins after rebel groups rise up against the Sudanese government.
 * – Former Bosnian Serb leader is sentenced by the United Nations  to 11 years in prison for war crimes committed during the.

March

 * – approves joining the  in.
 * n Prime Minister  by a sniper.
 * The issues a global alert on  when it spreads to  and  after originating in.
 * – The begins with the  of  by the U.S. and allied forces.
 * – approves joining the European Union and  in.
 * – approves joining the European Union and  in.

April

 * – U.S. forces, ending the of.
 * – approves joining the European Union in.
 * – The is completed, with 99% of the human  sequenced to 99.99% accuracy.
 * – The United States announces the withdrawal of its troops stationed in, and the redeployment of some at the in.

May

 *  table sculpture is stolen from the in.
 * approves joining the European Union in.
 * – In, Saudi Arabia, over 30 people are killed in , mostly foreign expatriates.
 * – approves joining the European Union in.
 * –, the first deer cloned by scientists at , is born.
 * – adopts a new constitution, which, among other things, changes the country's official name from "Rwandese Republic" to "Republic of Rwanda".
 * –, the world's first cloned , is born.
 * –, the world's first cloned , is born.

June

 * – approves joining the European Union in.
 * – The approves joining the European Union in.
 * – Warring parties in the sign a peace accord, bringing an end to the, which left millions dead.

July

 * – Severe acute respiratory syndrome is declared to be contained by the World Health Organization.
 * – The 70-meter Eupatoria Planetary Radar sends a message  to five stars: Hip 4872, HD 245409,,  and , that will arrive at these stars in , , May , September 2044 and  respectively.
 * – The finishes its work and proposes the first European Constitution.
 * – The, led by , begins after ethnic violence engulfs the island country.

August

 * - The occurred on 5 August 2003 in J.W. Marriott Mega Kuningan, South Jakarta, Indonesia, killing twelve people and injuring 150. The hotel was closed for five weeks and reopened to the public on 8 September.
 * The comes to an end after President  resigns and flees the country.
 * NATO takes over command of the in Afghanistan, marking its first major operation outside Europe in its 54-year-history.
 * - The cuts electricity to the northeastern United States and parts of Canada.
 * – One year old Zachary Turner is in, Canada. She had controversially been bailed and granted custody of the toddler despite facing extradition and trial for the murder of Zachary's father. The case inspired the movie  and prompted a change in Canadian law.
 * – The unmanned is launched from,.
 * makes its to Earth in over 60,000 years.
 * The first, involving South and North Korea, the United States, China, Japan and Russia, convene to find a peaceful resolution to the security concerns of the.
 * makes its to Earth in over 60,000 years.
 * The first, involving South and North Korea, the United States, China, Japan and Russia, convene to find a peaceful resolution to the security concerns of the.

September

 * – Europe's busiest shopping centre, the in, is officially opened.
 * – approves joining the European Union in.
 * – rebels kidnap eight foreign tourists at, , being freed 100 days later following negotiations with the Colombian government.
 * – approves joining the European Union in.
 * – The starts the, making 800 exposures, until January 16, 2004.
 * –, an unmanned spaceprobe and ESA's first mission to the moon, is launched from ,.

October

 * – i warplanes alleged Islamic jihad bases inside n territory, the first Israeli attack on the country since the 1973.
 * – China launches, their first.
 * – makes its last commercial flight, bringing the era of airliner  to an end.

November

 * – at an  military police headquarters in, , kills 17 Italian military police officers and nine Iraqi civilians.
 * –  resigns after  engulf the country following a disputed.
 * – The supersonic passenger jet,, makes its last ever flight from in London to.

December

 * –, the former , in the small town of  by the U.S. Army.
 * – agrees to eliminate all of its materials, equipment, and programs aimed at.
 * The becomes a specialized agency of the.
 * Chuandongbei natural gas field explosion, Guoqiao, Kai County,, China, killing at least 234.
 * – The 6.6  shakes southeastern  with a maximum  of IX (Violent), killing an estimated 30,000 people.
 * – The last known speaker of the dies, rendering it extinct.
 * – The last known speaker of the dies, rendering it extinct.