Goals: Voyager 1 and 2 were designed to take advantage of a rare planetary alignment to explore the outer solar system. Voyager 2 targeted Jupiter, Saturn, Uranus and Neptune. Like it's sister spacecraft, Voyager 2 also was designed to study the edge of our solar system beyond the planets.

Accomplishments: Voyager 2 is the only spacecraft to study all four of the solar system's giant planets at close range. It is now exploring the outermost reaches of where the solar wind and the sun's magnetic field dominate space. In September 2007, it crossed the termination shock (where the speed of the solar wind drops below the speed of sound) at 84 AU (about 13 billion km from the sun, more than twice the distance to Pluto). Since then, Voyager 1 has been operating in the heliosheath environment, a region about 40 to 50 AU (3.7 billion to 4.7 billion km) thick where the solar wind mixes with the interstellar wind.