March 31

On March 31, 1951, Remington Rand delivered the UNIVAC I (UNIVersal Automatic Computer I) to the United States Census Bureau. As the first commercial electronic digital computer produced in the U.S., UNIVAC I represented a major milestone in computing history. It could process data at unprecedented speeds, performing thousands of calculations per second. The Census Bureau used it to tabulate and analyze demographic information, streamlining the decennial census process. UNIVAC I's success demonstrated the practical value of large-scale computing for government and business applications. This delivery heralded the dawn of the computer age, paving the way for future technological advancements.

On March 31, 1966, the Soviet Union successfully launched Luna 10 aboard a Molniya rocket from the Baikonur Cosmodrome. After a voyage of two days, Luna 10 became the first human-made object to enter orbit around the Moon. The probe transmitted valuable data on lunar gravitational fields, radiation levels, and micrometeoroid impacts. Luna 10's achievements marked a significant milestone in the Space Race, showcasing Soviet prowess. It also collected scientific measurements via onboard instruments, contributing to our understanding of the Moon's environment. This mission paved the way for subsequent lunar exploration and influenced both unmanned and later manned space missions.

Explorer 1 was launched by the United States on January 31, 1958 as its first successful satellite. It carried scientific instruments that led to the discovery of the Van Allen radiation belts. The satellite transmitted data on cosmic rays and micrometeoroid impacts for over a decade as it orbited Earth. Over time, its altitude gradually decayed due to atmospheric drag. On March 31, 1970, Explorer 1 reentered Earth's atmosphere and burned up, concluding a pioneering chapter in space exploration.

On March 31, 1998, Netscape Communications Corporation made a landmark decision to release the source code of its flagship Navigator web browser. The code was published under the Netscape Public License, one of the earliest corporate open source licenses. This move aimed to foster community development and accelerate innovation in web technologies. The initiative led to the creation of the Mozilla Organization and eventually the Firefox browser. It marked a turning point in the software industry, encouraging other companies to embrace open source models. Developers worldwide were galvanized to contribute to an open web ecosystem. Today, Mozilla continues to champion an open internet, tracing its roots back to this foundational event.

On March 31, 2005, a team led by Michael E. Brown at the Palomar Observatory announced the discovery of Makemake, a large object in the Kuiper Belt. Using the Samuel Oschin telescope, they detected its slow movement against the backdrop of stars. In 2008, the International Astronomical Union officially classified Makemake as a dwarf planet. Named after the creator deity of Easter Island’s Rapa Nui culture, it joins Pluto and Eris among recognized dwarf planets. Makemake boasts a bright surface coated with methane ice and takes approximately 310 Earth years to complete one orbit around the Sun. The discovery expanded our understanding of the diverse bodies populating the outer solar system.

On March 31, 2016, NASA astronaut Scott Kelly and Roscosmos cosmonaut Mikhail Kornienko landed in Kazakhstan, concluding a yearlong mission on the International Space Station. The mission aimed to study the physiological and psychological effects of extended spaceflight in preparation for future Mars missions. During their 340 days in microgravity, they conducted over 300 experiments on bone density, muscle atrophy, and gene expression. Scott Kelly’s identical twin, Mark, participated as a ground-based control subject for comparative analysis. At the time, the mission set the record for the longest continuous spaceflight by an American astronaut. Data from their flight continues to inform plans for long-duration human exploration beyond low Earth orbit.