What is Retrograde Motion?
The term 'planets' comes from the Greek word for `wanderers',
because these bright objects appeared to be moving along the
stars (though always staying along the ecliptic!). But what
was most bizarre, is that the planets would be seen, over a period
of several weeks, to slow down in their motion, stop, move
backwards for a while, then continue back in their normal
easterly motion against the stars. This was called
Retrograde Motion.
To see the demonstration of retrograde motion of Mars below,
click RELOAD on your browswer and the animated gif
will restart again.
