Yes it has, by remote space vehicles, but not by humans directly.
yes, MESSENGER has explored Mercury. On March 18, 2011 a year from today, MESSENGER will transition from orbiting the Sun to being the first spacecraft ever to orbit the planet Mercury.
Mercury was explored by no one only observed.
john William has explored the planet mercury... but no one has been sent out to this planet
mercury
no one has ever been to mercury because there is not enough oxygen and it is too hot.
No space probe has ever landed on Mercury.
No.
From what I have learned, there has not yet been a robot that explored Mercury from closeup. They see Mercury since it is able to be seen by the naked eye in certain times of the night and day. It can also be seen with a telescope. So in all: There has not yet been a robot to explore Mercury from what I know. I apologize if this is incorrect.
in terms of satalites and rovers, mars, venus, jupiter, saturn, mercury
no robots have roamed Mercury
We do not know, since no man has ever been to Mercury.
There have been two space probes: Mariner 10 and Messenger.