What planets have been visited by spacecrafts?
The planets that have been visited by spacecrafts are: Mercury, Venus, Mars, Jupiter, Saturn, Uranus, and Neptune. This means that the only planet in our Solar System that has not yet been visited is Pluto.
The New Horizons spacecraft
Actually, the New Horizons spacecraft is on it’s way to visit Pluto, and is scheduled to be there by the year 2015.