September 21, 2026 – Historical Events & Birthdays
September 21 marks important moments in Arizona and American history, along with milestones in space exploration and world affairs. Here are several notable events associated with the date.
🌍 Politics & World History
1777 – Battle of Paoli
British troops attacked an American encampment near Paoli, Pennsylvania, during the Revolutionary War. The nighttime action became known as the “Paoli Massacre,” although historians have debated the terminology and interpretation.
1784 – Pennsylvania Packet begins publication
The Pennsylvania Packet and Daily Advertiser began publication in Philadelphia, becoming the first successful daily newspaper in the United States.
1864 – Battle of Fisher’s Hill
Union forces defeated Confederate troops at Fisher’s Hill in Virginia’s Shenandoah Valley. The victory was an important part of Philip Sheridan’s campaign and weakened Confederate control of the region.
1981 – Sandra Day O’Connor confirmed to the Supreme Court
The U.S. Senate confirmed Arizona native Sandra Day O’Connor by a 99–0 vote, making her the first woman to serve on the United States Supreme Court. Her confirmation remains a landmark in both Arizona and American legal history.
1964 – Malta becomes independent
Malta became independent from the United Kingdom while remaining within the Commonwealth. The United States established diplomatic relations with Malta and opened its embassy in Valletta that same day.
🔬 Science & Technology
1932 – High-altitude cosmic-ray experiments
Physicist Robert A. Millikan completed a series of cosmic-ray measurements using a Condor bomber over California. The experiments contributed to early efforts to understand high-energy radiation arriving from beyond Earth.
1966 – Project EROS announced
Interior Secretary Stewart Udall announced Project EROS, an early step toward the Landsat program’s long-term satellite study of Earth’s surface and resources. The effort has particular relevance to the Southwest, where satellite observations support the monitoring of deserts, water, agriculture and wildfire.
1968 – Zond 5 returns from a lunar flight
The Soviet Zond 5 capsule returned to Earth after circling the Moon and splashed down in the Indian Ocean. The spacecraft carried living organisms, including steppe tortoises, and demonstrated capabilities important to future lunar missions.
2014 – MAVEN enters orbit around Mars
NASA’s Mars Atmosphere and Volatile Evolution spacecraft entered orbit around Mars. The mission studies how the planet’s upper atmosphere interacts with the Sun and how Mars has lost atmospheric gases.
Summary
September 21 connects Arizona’s history to national milestones, from Sandra Day O’Connor’s Supreme Court confirmation to Stewart Udall’s role in advancing Earth-observation research. The date also recalls important Revolutionary and Civil War battles, Malta’s independence, and major advances in lunar and Martian exploration.
