October 29

In 1675, the polymath Gottfried Wilhelm Leibniz first used the long s (∫) to denote the integral in his correspondence on mathematical analysis. Borrowed from the Latin word “summa,” the symbol elegantly represented the summation of infinitesimal quantities. Leibniz’s notation was part of his broader development of differential and integral calculus, conducted independently of Newton. His clear symbolic approach facilitated the rapid spread and teaching of calculus across Europe. Today, the integral sign ∫ remains a fundamental element of mathematical notation, reflecting Leibniz’s enduring influence on the discipline.

On October 29, 1969, researchers at UCLA and the Stanford Research Institute successfully established the first direct communication between two computers over ARPANET. The experiment saw the transmission of the letters 'L' and 'O' before the system crashed, marking the dawn of networked computing. ARPANET, funded by DARPA, evolved into the Internet by adopting packet-switching and TCP/IP protocols. This milestone enabled shared resources, remote access, and eventually global digital communication. The achievement reshaped technology, business, and society by enabling instantaneous information exchange across continents.

During its journey to Jupiter, the Galileo spacecraft performed a historic flyby of asteroid 951 Gaspra on October 29, 1991. Passing within 1,600 miles of the small, irregularly shaped body, Galileo captured the first close-up images of an asteroid’s surface. Scientists discovered a heavily cratered landscape with evidence of landslides and dust deposits. The mission provided invaluable data on asteroid composition and morphology, shaping our understanding of these ancient solar system remnants. The close encounter demonstrated the potential for future asteroid exploration and planetary defense research.

On October 29, 1998, NASA’s Space Shuttle Discovery lifted off on mission STS-95, carrying a diverse crew and the returning American icon, John Glenn. At age 77, Glenn became the oldest individual to travel into space, providing insights into the effects of spaceflight on aging. The mission conducted various scientific experiments on microgravity’s impact on human physiology, materials processing, and astronomy. Glenn’s participation sparked public interest and underscored the Shuttle program’s versatility. STS-95’s success added valuable data to long-duration spaceflight research and celebrated a living legend’s return to the stars.

On October 29, 1998, the US officially launched ATSC HDTV broadcasting alongside NASA's STS-95 space shuttle mission. This marked the beginning of high-definition television under the Advanced Television Systems Committee standard. The joint initiative combined cutting-edge space exploration with a new era of digital broadcasting. Viewers began accessing vastly improved picture and sound quality in homes across the nation. The innovation paved the way for widespread HDTV adoption and set a new benchmark in broadcast technology.