Voyager 2

Voyager 2 is a NASA space probe launched on August 20, 1977, to study the outer planets. It is the only spacecraft to have visited Uranus and Neptune, providing invaluable data on these planets and their moons. Voyager 2 is now in interstellar space, continuing to send data back to Earth.

Source: science.nasa.gov

APODs including "Voyager 2"