On November 3, 1957, the Soviet Union launched the Sputnik 2 spacecraft into Earth orbit. This mission marked a significant milestone in space exploration, as it was the first time a living being—a female dog named Laika—was sent into space. Sputnik 2 followed the earlier success of Sputnik 1 and became the second artificial satellite to reach orbit, with the specific goal of studying the effects of spaceflight on living organisms. Laika was placed in a specially designed compartment equipped with medical monitoring devices to track her vital signs during the mission. The total weight of the spacecraft was about 508 kilograms, and Laika was the only living passenger on board. Data collected from this flight provided valuable insights into the physiological responses of living beings in microgravity, paving the way for future human space travel. The event received worldwide attention and intensified the space race between the Soviet Union and the United States. The launch of Sputnik 2 and Laika’s journey are recognized as major milestones in the history of technology and space science. This date is often noted in calendars as a reminder of scientific progress and the ethical challenges associated with early space experiments. This observance was added to the Gregorian calendar after the event in 1957 to commemorate the beginning of a new era in space exploration.
