<P> The exploration of Neptune has only begun with one spacecraft , Voyager 2 in 1989 . Currently there are no approved future missions to visit the Neptunian system . NASA , ESA and also independent academic groups have proposed future scientific missions to visit Neptune . Some mission plans are still active , while others have been abandoned or put on hold . </P>
<P> The exploration of Neptune has only begun with one spacecraft , Voyager 2 in 1989 . Currently there are no approved future missions to visit the Neptunian system . NASA , ESA and also independent academic groups have proposed future scientific missions to visit Neptune . Some mission plans are still active , while others have been abandoned or put on hold . </P>
when was neptune last visited by a spacecraft
when was neptune last visited by a spacecraft
1989
1989