Answer 1:
The short answer to your question is no, not
all planets rotate in the same direction.
However, we should clarify some thoughts to avoid
confusion. When we talk about which way a planet
is rotating, it is important to specify our frame
of reference. Why? Well, for instance, form a
"thumb's up" with your right hand. Notice how your
fingers curl from right to left when you look down
at your hand. Now, turn your right hand upside
down and make a "thumb's down." From your
perspective (still looking down at your hand),
your fingers should curl from left to right.
Does that mean that relative to your thumb your
fingers are curling differently? Isn't your
right hand still your right hand? And how
would you standardize this -- how would you
explain to another person which way your fingers
are curling? This is why explicitly stating
our frame of reference is important.
So if we choose our frame of reference to be as
if we're standing above north end of the axis of
rotation (e.g. roughly the North Pole on Earth)
and looking "down" at the rest of the planet, we
would see that most of the planets in our solar
system rotate counter-clockwise (sun rises in the
East). Most of the planets, dwarf planets, and
other bodies in the solar system exhibit this
prograde, counter-clockwise rotation.
However, an example of an exception to this
would be Venus, which has a "retrograde"
rotation and rotates clockwise, very slowly -- it
takes about 243 earth days for it to rotate once
about its axis!
One further observation to note: when a galaxy
or other celestial system forms, the material in
the system usually forms a disk and most of the
material will orbit and rotate in the same
direction. This can be explained by the fact that
these systems will try to conserve angular
momentum. However, motion against the
direction that the majority of objects in the
system exhibit can occur for a number of reasons,
usually in the form of interactions (e.g.
collisions or gravitational interactions) with
other bodies in the system. I hope this is
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