Today in History: Voyager 1 photographs Earth and Moon together from space

Here are some of the most significant moments that happened on September 18:

324 – Constantine unites the Roman Empire at Chrysopolis

On September 18, 324, Constantine the Great decisively defeated his rival Emperor Licinius at the Battle of Chrysopolis, ending years of civil war. This victory made Constantine sole ruler of a reunified Roman Empire, abolishing Diocletian’s Tetrarchy system. In the aftermath, Constantine founded Constantinople (modern Istanbul) as a new imperial capital to commemorate the win and solidify unity. The reunification of the empire under one emperor paved the way for the Christianization of Roman governance and a more centralized state, profoundly shaping the religious and political trajectory of Europe.

1759 – Fall of Quebec shifts control of North America

On September 18, 1759, during the Seven Years’ War, French forces in Canada surrendered Quebec City to the British. The Articles of Capitulation of Quebec were signed that day, just days after Britain’s victory at the Plains of Abraham, officially handing Quebec over to British control. This was a pivotal turning point in North American history – the fall of France’s colonial stronghold in Canada. Within the next year, the remaining French forces in Montreal also capitulated, and in 1763 the Treaty of Paris ceded Canada to Great Britain. The British triumph at Quebec effectively ended French colonial rule in North America and reshaped the continent’s political map.

3. 1810 – Chilean independence movement begins

On September 18, 1810, as Spain was embroiled in Napoleonic turmoil, Chilean patriots in Santiago formed the First National Junta, the country’s first autonomous government. Although initially claiming loyalty to the deposed Spanish king, this Junta marked Chile’s first step toward independence from Spanish colonial rule. The date is celebrated as Chile’s Independence Day (Fiestas Patrias) because it ignited the Chilean War of Independence. The establishment of local rule in 1810 rallied Creole leaders and common citizens alike, leading to full independence by 1818.

1812 – The Great Fire of Moscow turns Napoleon’s tide

Between September 14–18, 1812, a massive fire engulfed Moscow during Napoleon Bonaparte’s occupation of the city. By September 18 the flames had destroyed over three-quarters of Moscow – thousands of buildings and hundreds of churches were reduced to ruins. Russian officials had deliberately set fires as a scorched-earth tactic to deny the French army shelter and supplies. The devastation forced Napoleon to realize there was nothing left to sustain his troops. Lacking provisions and facing the onset of winter, he abandoned Moscow in October 1812, beginning the disastrous retreat from Russia. This turning point in the Napoleonic Wars shattered the myth of Napoleon’s invincibility and contributed directly to his empire’s downfall.

1873 – Panic of 1873 triggers the first global depression

On September 18, 1873, the influential American banking firm Jay Cooke & Company collapsed, sparking a chain reaction of financial failures. Jay Cooke’s bankruptcy on that day sent shockwaves through stock markets, causing a panic that led the New York Stock Exchange to suspend trading. Heavily invested in over-extended railroad projects, the bank’s failure precipitated widespread bank runs and railroad bankruptcies. The ensuing Panic of 1873 unleashed a severe economic depression in both North America and Europe, often considered the first global depression of the industrial age. Over the next several years, unemployment soared and thousands of businesses failed, reshaping financial systems worldwide.

1898 – Fashoda Incident brings imperial rivals to brink of war

On September 18, 1898, a tense imperial standoff in the Sudan nearly ignited war between Britain and France. At a remote Nile outpost called Fashoda (now Kodok, South Sudan), French Major Marchand’s expedition – having crossed Africa – was met by British General Kitchener’s gunboat forces coming from Egypt. Both nations sought to link their African colonies, and the encounter at Fashoda became the climax of their colonial disputes. For weeks, both flags flew over the fort as the world watched the “Fashoda Incident,” the last great war scare between Britain and France. Eventually, France, unwilling to risk a major war, ordered Marchand to withdraw in November. The peaceful resolution paved the way to the 1904 Entente Cordiale, ending decades of rivalry and ushering in a new era of Anglo-French cooperation.

1931 – The Mukden Incident sparks Japanese invasion of Manchuria

On the night of September 18, 1931, Japanese officers staged an explosion on the South Manchuria Railway near Mukden (today Shenyang, China) and falsely blamed Chinese saboteurs. This orchestrated event – known as the Mukden Incident – gave Imperial Japan a pretext to launch a full-scale invasion and occupation of Manchuria. In the immediate aftermath, the Japanese army seized Mukden and within three months had overrun all of Manchuria, establishing the puppet state of Manchukuo. The Mukden Incident’s impact was far-reaching: it marked the beginning of Japan’s aggressive expansion in East Asia and undermined the credibility of the League of Nations. It is often considered a precursor to World War II in the Pacific.

1947 – National Security Act reshapes U.S. defense and intelligence

On September 18, 1947, the U.S. National Security Act of 1947 took effect, radically reorganizing America’s post-war military and intelligence apparatus. The law merged the U.S. War and Navy Departments into a unified Department of Defense and established the U.S. Air Force as an independent service branch. It also created the National Security Council (NSC) to coordinate defense and foreign policy, and the Central Intelligence Agency (CIA) as the nation’s first peacetime intelligence agency. These changes provided the bureaucratic framework for U.S. strategy throughout the Cold War. The implementation of the Act is seen as a foundational moment in modern U.S. defense and intelligence history.

1973 – East and West Germany admitted to the United Nations

On September 18, 1973, both German states joined the United Nations, a milestone in Cold War détente. The Federal Republic of Germany (West Germany) and the German Democratic Republic (East Germany) were officially admitted as UN member states on the same day, alongside the newly independent Bahamas. Their dual admission acknowledged the political reality of two Germanys and came after the landmark Basic Treaty of 1972, in which each German state agreed to respect the other’s sovereignty. This was the first time they sat together in a global organization, symbolizing a step toward normalization of relations despite the ongoing division of Germany.

1977 – Voyager 1 photographs Earth and Moon together from space

On September 18, 1977, NASA’s Voyager 1 spacecraft – at a distance of 7.25 million miles from Earth – captured an unprecedented photograph: for the first time, Earth and its Moon appeared together in a single frame seen from space. The image showed a thin crescent Earth with the tiny Moon beyond it against the blackness of space. This first portrait of the Earth-Moon system taken by a spacecraft provided humanity a striking new perspective on our home planet. The photo was a scientific and cultural milestone, underscoring the Earth’s fragility and unity, and it became a prelude to Voyager’s even more distant “Pale Blue Dot” image years later.