Posted on 07/30/2015 1:41:07 PM PDT by BenLurkin
The only way to get gravity is with mass. The more mass, the more gravity you get. Without mass, you can’t have gravity.
...
The force of gravity that we feel is actually just an acceleration towards the center of the Earth at 9.8 meters per second squared, or 1G.
If you were in a spacecraft and it was accelerating away from Earth at a rate of 1G, it would feel exactly the same if you were standing on the ground.
... Want to fly to Jupiter? It would only take about 80 hours of acceleration, and then 80 hours of deceleration. At the halfway point of this journey, you’re going more than 2,800 kilometers per second, which is close to 1% the speed of light.
Want to travel a light-year? Accelerate for about a year, then decelerate for a year. At the mid-point, you’ll be going the speed of light.
Uh oh. There’s the problem. As you probably know, as you approach the speed of light, it requires more and more
There’s an idea that I’m sure you Arthur C Clarke fans know, which requires way less energy: artificial gravity from centripetal force…
To make this comfortable, you need a ring-shaped spacecraft with a radius of 250 meters. This ring would need to turn about twice a minute for astronauts within the spacecraft to experience 1 G.
Building a spacecraft like this is an engineering challenge, but it’s probably within reach of our current technology.
Something like this would help us explore the Solar System without the health risks of microgravity.
...It’s going to be huge rotating rings for the foreseeable future, sadly.
(Excerpt) Read more at universetoday.com ...
I defied a Newtonian Law once.
The judge gave me ninety days.
Mass or acceleration (spinning works). No other way to create gravity.
An argument has been made that gravity is virtual, not a thing in itself, but an effect caused by the curvature of space by mass.
To start with, under many circumstances, time and space seem to be two dimensions of the same thing. Change one and you change the other. And if you are familiar with Einstein’s two dimensional grid model of space, you know that mass acts upon space by deforming it, also deforming time in the process.
The hard part, much more difficult to conceptualize, is that the grid is actually three dimensional, so bodies with mass deform space all around it, towards it. And this deformation of space and time is such that it seems to do what gravity does, but without the need for gravity.
In any event, this perhaps makes creating “artificial gravity” easier, because instead of manipulating gravity, you manipulate space time like mass does.
True but there is a beauty to the ring.
Some of the best. Firefly, if allowed to live may have become a rival.
Gravity from one million light years away effects us, so imagine traveling on
a wave of gravity to anywhere at any speed. Watch out for that one speck of
dust at high speeds though, one particle and it's curtains.
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