|If the earth spin the opposite direction wouldn't
that change gravity and the way things will go?
If the spinning of the earth go to the east, and
if we would change the way it could put the
|Question Date: 2017-10-30|
Gravity is a universal force that acts on all
objects -- it essentially tries to bring objects
closer together, and it works on objects
regardless of their spin/movement.
The reason that we stay "attached" to the Earth's
surface is that the earth is massive, so it exerts
significant gravitational force on us. Although
the Earth's spin does affect gravity slightly, if
the earth were to stop spinning (or spin the other
direction) gravity would still keep everything
in its place. One interesting related fact
about gravity is that the acceleration due to
gravity is actually slightly smaller in magnitude
at the equator than at the poles because of
centrifugal force caused by the Earth's spin, so
you would weigh less at the equator than you do
Actually, the direction that the earth spins
doesn't really affect the earth's gravity.
Gravity is something that depends on the mass
and size of something. So anything that has
mass has gravity. That means that even YOU
have your own little gravitational field, but it's
not a very big gravitational field because you
don't have that much mass. The Earth's gravity
is a force that pulls you towards the earth.
Things that are spinning really quickly, like
the earth, actually create a force that moves in
the opposite direction of gravity. So because the
earth is spinning, it's actually creating a second
force, called "centrifugal force" that
pushes you away from the earth a little bit. To
understand this, try a little experiment: take a
yo-yo or tie something like a pencil to the end of
a string. Hold the other end of the string and
start spinning in a circle really quickly. What
happens to the pencil or the yo-yo? It moves
away from you! This is what's happening on Earth.
It actually causes our planet to bulge a little
bit around the equator: instead of being a perfect
sphere, we're a little more football shaped.
Luckily the earth's gravity is much bigger than
centrifugal force so we don't go flying off of our
planet. If the earth were spinning the other
way, all of the forces would balance out like they
do now so the gravity that we feel wouldn't change
Hey, super cool question!
Lets start interesting background about your
question. The reason the earth spins the way it
does is because it was basically "born" that way.
When our sun (which is in the Milky Way) formed,
it began pulling dust floating around in space
towards it. This is due to the gravity of the sun.
This dust started to move in a circle around the
sun, and over millions and millions and millions
of years, this dust began clumping together, and
eventually formed Earth (as well as all the other
planets in the Milky Way like Venus and Mars and
all the others). So the spinning of our earth
was basically decided based on how dust first
started circling our sun.
Most planets in the Milky Way spin in the same
direction as Earth, but some planets do not...
why is that? Well, its because something
HUGE smashed into them with so much power that it
actually made them start spinning the other way.
Think about that. That's amazing! So how would
the earth start spinning the other direction?
It would only be possible if something really big
smashed into it (like a really big meteor or
But what exactly would happen if the earth
started spinning the other way...Well, it would be
pretty bad. But the main effect would be that
all the weather on Earth would change. You
should look at this cool website, it shows all the
wind patterns and storms on earth happening right
All weather patterns on Earth are caused by
the spin of the earth. If the spin changed, so
would the weather. For example, all storms in the
top half of the earth spin one way, and those on
the bottom half spin the other way because of
which direction the earth is spinning. So even by
changing spins of storms, you change where they
will go and how they will behave - changing a lot.
Hurricanes just like the ones that hit the
United States and Mexico will go different places,
and might even be more powerful!
But what would be worse than the earth
spinning the other direction....? If Earth
stopped spinning all together!!
See if you can figure out what might happen!
Hint: it has to do with the big magnetic
field caused by the earth spinning.
Gravity keeps us from hopping from our porches
into outer space. Even though we can't jump
into space, the Earth's spinning makes space
travel easier. In fact, the U.S. launches rockets
from Cape Canaveral in Florida because the
rotation of Earth can give a starting boost for
rockets–kind of like a slingshot.
How could we make the earth slingshot
stronger? We would need to make the earth spin
more than 20 times faster to jump off the face of
You can think about the earth like a top.
Places near the top and bottom aren't moving as
quickly as those which whip around the center.
Although polar bears and penguins spin slowly they
don't fly off to the Moon or Mars. That's
because gravity makes them stay here!
The spin of the earth has nothing to do with
gravity. The earth has gravity because it has
mass, and changing the spin would not change the
Great question! The gravity between two objects
(such as you and the earth) depends only on their
mass (weight, effectively) and the distance
between them. Gravity would pull on you just
the same if the earth wasn't spinning or spun in
the opposite direction. Why?
Fundamentally, we don't fully know.
However, the force you feel on the surface of
Earth isn't only gravity and other parts of it
would be affected by the reversal of Earth's
For instance, there's the relatively weak
"centrifugal force" that pushes you outward
when moving in a circle, which you can feel in
many amusement park rides or even a tire swing.
This depends on how fast Earth rotates,
though not which way. However, if Earth were to
rotate around a different axis--right now, the
North pole is on top, but imagine your school
was--this centrifugal force would point away from
this new axis instead. What I mean by axis is
easily visualized by looking at a spinnable
globe--the stick it spins around is its rotational
What is changed by the direction of Earth's
rotation is the "Coriolis force," which would
flip directions if Earth spun in the opposite way.
While this force is also much smaller than gravity
(it's generally unnoticeable) and only affects
moving objects (like a thrown baseball), it would
have a few noticeable effects such as changing the
direction of how hurricanes spin! Right now,
hurricanes spin counterclockwise north of the
Equator (and revere south of it), but these depend
on the Coriolis force and would switch!
Another interesting effect of reversing the
earth's rotation is that its protective
magnetic field(due to molten metals moving in
the core) would be likely flipped upside
down. This means compasses would point south!
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