Is artificial gravity in space really possible?
Some magazines and books talk about a space station
spinning slowly to form artificial gravity, but
does this work?
Gravity in the traditional sense is the interaction of masses, for
example the earth and the sun.
When no mass is present one can create a similar effect by generating g
forces through rotation. This is called the centripetal force, and you
experience it on a roller coaster or even when a car turns to quickly.
Well, gravity is a force that acts between all objects with mass. With
this "artificial gravity," the space station will not actually be
generating new gravity; the only real way to do that is to generate more
mass. Rotating, however, will generate a force that will cause anyone
inside the spaceship to "fall" to the outside of the spaceship, provided,
that is, that they are moving with the spaceship. It will be like gravity
in that objects will "fall" to the floor (acdtually, the floor will move up
to them), but there will be some odd differences. The force of the
attraction will change depending on the direction that you move. If you
move in the direction of the rotation, the force will increase; if you move
opposite the direction of rotation, the force will decrease to zero when
your speed exactly cancels the speed of rotation, and then will increase
again as you move faster than the speed of rotation.
Richard Barrans Jr., Ph.D.
Yes, it works because that is the nature of a spinning object. Earth's
gravity in its simplest form is an acceleration towards the center of the
earth. When an any object spins, an acceleration is generated toward the
center of that object. So, if you spin a space station at a certain rate,
you will create an acceleration that resembles the gravity here on earth.
The space stations in orbit now (like MIR) are not designed to spin, but new
stations in the future may be designed to spin so that we can have a more
earth-like station in space someday.
Dr. C Murphy
It sure would work. It works the same way you can hold a bucket of
water upside down and have the water not fall... if you keep moving it
in a circle. However, if you stop with it upside down, you get wet.
This is related to Newton's first law of motion - inertia. You might
want to look this up along with related terms - centrifugal and
centripetal force. You also might find the opening scenes of 2001 - a
Space Odyssey interesting.
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Update: June 2012