First spacecraft to leave the heliosphere

NASA's Voyager 1 is recognized as the first spacecraft to leave the heliosphere, marking a pivotal achievement in space exploration. The heliosphere is a vast bubble created by the solar wind, which is a stream of charged particles emitted by the Sun. Voyager 1's journey began in 1977, and it was designed to study the outer planets of our solar system. After completing its primary mission, Voyager 1 continued its trajectory outward, gathering data about the environment beyond the influence of the Sun. The spacecraft's departure from the heliosphere signifies its entry into interstellar space, an area that is not dominated by solar wind and is instead filled with cosmic rays and other interstellar matter. This transition provides scientists with invaluable data about the boundary between our solar system and the rest of the galaxy, enhancing our understanding of space physics and the nature of the universe.