May 31

On May 31, 1790, Spanish naval officer Manuel Quimper charted the coast around the Strait of Juan de Fuca. Sailing under the Spanish flag, he navigated these waters to establish Spain's territorial claims in the Pacific Northwest. Quimper's expeditions produced some of the first detailed maps of Vancouver Island's southern coastline. His work aided future explorers and traders by improving knowledge of regional geography and safe passage. The voyage contributed to the intense competition among European powers for control of North American territories. Quimper's charts remained valuable reference points for decades after his return to Spain.

The Great Clock at the north end of the Palace of Westminster began operation on May 31, 1859, with its first formal timekeeping. Designed by Edward John Dent and completed under his son Frederick, the clock mechanism featured unprecedented accuracy for its era. The Elizabeth Tower (then known simply as the Clock Tower) housed the Great Bell, nicknamed Big Ben, which rang its first chime that day. The clock's four face dials were engineered to be seen from great distances across the Thames. Its reliable timekeeping quickly became a symbol of British engineering prowess. Daily maintenance routines and the distinctive chimes ingrained Big Ben into London's cultural identity. Over the years, the clock and its tower have weathered wars and renovations to remain an enduring landmark.

On May 31, 2008, Space Shuttle Discovery lifted off on STS-124, carrying the Pressurized Module of the Japanese Kibō laboratory to the International Space Station. The mission’s crew performed complex spacewalks to install and integrate the new section, enhancing the station’s research capabilities. Kibō, meaning 'hope' in Japanese, represents Japan’s largest contribution to the ISS. Discovery’s successful delivery allowed astronauts to conduct experiments in microgravity across biology, materials science, and medicine. The flight underscored international cooperation in space exploration and the shuttle program’s role in ISS assembly. STS-124 set the stage for subsequent missions completing the Japanese research complex.

In the evening of May 31, 2013, near-Earth asteroid 1998 QE2, measuring roughly 2.7 kilometers in diameter, approached our planet at a distance of about 5.8 million kilometers. Accompanied by a satellite estimated at 600 meters across, it marked the closest flyby of this binary asteroid system for at least two centuries. NASA's Goldstone Solar System Radar captured high-resolution images of both bodies, revealing detailed surface features and refining orbital models. Scientists used these observations to enhance understanding of asteroid composition and dynamics, vital for planetary defense. Despite its proximity, the asteroid posed no threat to Earth, and the successful observations highlighted advances in radar astronomy. The event remains one of the most closely studied near-Earth object encounters to date, offering insights into binary asteroid behavior.