Most of us take gravity for granted without realizing that its existence is essentially the difference between the Earth being habitable and a deathly chunk of rock with no life in sight. We come across different concepts through all kinds of sci-fi films or novels, but today, we are going to dwell upon some real-life techniques being used or under consideration for creating artificial gravity.
The TV series and movies like 2001: A Space Odyssey, Elysium and Superted‘s space station depict some methods of artificial gravitation that are considered as generally accepted solutions in the avenues of science. These solutions include centrifugal forces, and some are found to involve magnetism or “supernatural fields” to provide the desired effects.
This solution uses a fast-rotating spinning cylinder, torus or sphere. The idea is to use centrifugal force, which is the result of the centripetal force on an object moving in a circular path and the object’s inertial movement away from the axis of rotation. This force would “pin” the astronauts to the outside edge of the spinning object.
The centripetal force is directly proportional to the mass and velocity squared of the spinning object while inversely proportional to the distance from the center of rotation. So, you can vary the radius and rotating speed to fine tune the simulated “gravitational” force.
This force is similar to what you feel in fast rotating rides at an amusement park, where besides getting nauseous; you also feel a push towards outside. Interestingly, NASA did conduct various experiments during the 1960’s and proved this method to be theoretically viable.
Problems with rotational gravity
Using a rotating craft means that its radius of rotation needs to grow with the square of the orbital period, and doubling that time would require four times increase in the rotation. So to simulate Earth’s gravity, a craft with a radius of 56 meters would be needed if our orbital period was 15 seconds. A time of 30 seconds would require the radius to be increased to 224-meter, and so on. The delivery of materials in such amounts to space will be very expensive, and the movement into space would become even more improbable.
This solution uses the Newton’s third law of motion by simply producing enough linear acceleration to “pin down” the astronauts in the opposite direction. This would be highly desirable since it would lead to shorter flight times, but anything that is not fixed at some platform would start falling towards the hull which is a big problem since astronauts and objects would need to move about at some point in their flight.
Theoretically, a production of 1 g average linear “Gravity” during acceleration would enable the spacecraft to reach Mars in just a few days!
The concept of magnetism has been under study for many years, with the researchers amazingly been able to levitate mice using high-powered magnetic fields. The experiments simulated around 1g of Earth’s gravity but these magnets require very expensive cryogenics to keep the superconductivity, along with a massive supply of power.
Hypothetical gravity generators
A Russian Engineer, Eugene Podkletnov claimed to create a device back in the 90s which made gravitomagnetic fields, but his claim remained unverified by third parties.
Another research group, funded by ESA, claimed a similar invention in 2006, but their machine only managed to create around 0.0001g and wasn’t able to replicate the results.
The String theory also predicts the unification of gravity and electromagnetism in hidden dimensions, along with being able to “generate” gravity in the future. The potential existence of “graviton“ particles deemed responsible for gravity, may also result in finding a plausible solution to create artificial gravity.
Sources: livescience.com, popularmechanics.com
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