Every planet except Pluto has been explored by spacecraft.
The only manned missions to any celestial body of course are the Apollo missions to the moon and that is not a planet.
=== === Well, mars has been landed on by the most spacecraft, but that is robot spacecraft. The moon, not a planet, has had the most human life put on it.... as far as we know.
First Fly By:
Mars with Mariner 4 in 1965
First landing (or at least crash):
Venus with Venera 3 in 1966
Earth. Mars is second.
Depends on whether you say Pluto is a planet or not. If you say it isn't, then there are no planets that haven't been visited by a spacecraft. If you say it is, then there is one that hasn't been visited yet, but one is on the way.
Pluto has yet to be visited by a spacecraft because it is so far away.
yes, spacecraft have visited Mars, but the results haven't always been positive. More than half of the attempts to send a spacecraft to the planet have failed.
Mars has constantly been visited by spacecrafts. The first spacecraft to visit Mars was the Mariner 4. After that Mars has been visited by numerous spacecrafts like: Mars Pathfinder, Mars Global Surveyor, Mars Odyssey, Mars Express and the Mars 2 which was the first spacecraft to land on Mars.
No human has really visited any planet other than Earth; the Moon isn't a planet. However, spacecraft have visited other planets, such as the Spirit and Opportunity rovers, who went to Mars
No spacecraft has visited all the planets.
venus was the first planet visited by the American spacecraft
voyager 2
It's the closet and rather similar to the earth.
The First Aircraft that ever visited the planet is the dumbest question, Don't you know how to specify questions fool?
All of the eight planets have been visited or orbited by space probes.