Voyager Interstellar Mission

To learn more about our solar system and beyond, NASA (National Aeronautics and Space Administration) launched two unmanned probes, Voyager 1 and Voyager 2. Their primary mission was the exploration of Jupiter and Saturn. After reaching there and making a string of discoveries - such as the active volcanoes on Io (Jupiter's moon) and the patterns and composition of Saturn's rings - the mission was extended. Voyager 2 went on to explore Uranus and Neptune. It discovered the other moons of the planets and is still the only spacecraft to have visited those outer planets. The current mission (The Voyager Interstellar Mission), will explore the outermost edge of the Solar System and beyond.

The mission objective is to extend exploration of the Solar System beyond the outer planets to the outermost limit of the Sun's influence and possibly beyond. The extended mission is to study and observe the outer solar system environment and to search for the heliopause, the outer limits of the Sun's magnetic field. Reaching here will allow various  measurements to be made of interstellar fields, particles  and waves.

If the Voyager 2 happens to pass even the heliopause, it is estimated that in 40,000 years, Voyager 2 will pass 1.7 light years (9.7 million miles) from the star Ross 248 and in about 296,000 years, it will pass 4.3 light years (25 trillion miles) from Sirius, the brightest star in the sky. The Voyagers are destined - perhaps eternally - to wander the milky way.