Back in the good old days, "planets" were defined as wanderers in the sky: Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn. Then telescopes discovered Uranus, Neptune, and many more. So they added Earth to the definition of planet, and subtracted Sun and Moon (which I still call planets, in honor of my 3rd-grade teacher), and others. Here's the list. https://en.wikipedia.org/wiki/List_of_former_planets
I'm still bitter about the Sun and the Moon. Ceres, the first asteroid they found and declared a planet, was after my time, so who cares about that one. You guys want to start a movement with me?
The sun and moon have never been considered planets since at least the start of the 50s. The sun is a star and the moon is a moon since it revolves around a planet. This has been the story for at least over a half a century and probably much longer.
I thought spinning was part of gravity though. So mass is the only thing that matters for gravity? I thought space stationts spin to create artificial gravity? Or is that just the movies?
What you're thinking of is the illusion of gravity through rotational velocity's affect on centripetal acceleration. And we don't do that, except in the movies. Yet?
No, I don't think spinning is part of gravity, although I am not so sure anyone can give you a precise answer as to what is gravity, but yeah mass seems to be it. I don't know about the space stations but, from what I observe from videos is, the spinning would create somewhat the illusion of gravity to a person and object inside the craft. The force from the spinning is centrifugal force, outward to the walls of the craft, instead of gravity pulling to the center. I do not know, just my observations. Ha! Thought about it some more, damn you! But centrifugal force from spinning would counter gravitational force so we might be too heavy if the earth did not spin. I think that is how we get satellites to orbit. They spin about the earth generating centrifugal force to balance the gravitational pull of earth. The speed has to be in fit the orbit size. I remember about 20 years ago, they were letting out wire toward earth from a satellite for some experiment. The wire was several miles long, but the whole thing failed when the wire broke from "unknown forces". Just hearing the tale on the radio, I exclaimed, Well how the hell did they expect that to work! My wife say, what do you mean? Well letting out a long wire like in that will intersect the earth magnetic field and it will act just like a generator, the longer the wire the more power it generates. At some point, something has to give. Never did hear what the problem was though.
ya the point of my retarded questions was to question if globe earth is spinning why centrifugal force doesnt throw us into space. People on the equater should weigh less than people near the poles as the centrifigul force should be pullung them from "gravity" with far more force. Im still leaning toward flat earth theory. I dont give a fuck what nasa tells us.
I think the centrifugal force is equal everywhere on earth, as the RPM is too. As the distance from the center axis changes, so does the rotational velocity to keep the force equal. Correction! Typed bs here.
I mean, there's still "strong gravitational" force. As in gm1m2/r^2. In an awesome coincidence, the rotation of the earth is so balanced with the radius/mass of the earth such that a) you don't get tossed into space and b) you don't get smushed like a dime against the face of the earth (Like you would on, say, Jupiter).
Ha! These thoughts come to me when people speak of space travel. Especially as if we will do it! Man if you convert all the numbers to non dimensional numbers, such as Reynolds's numbers for speed. You begin to see, we humans were designed to be right here. We are converted to junk damn near everywhere else.
Uh oh! thought of some more complications. Gravity only directly opposes the centrifugal force of the spinning at the equator where the force vectors are in the same plane. Move toward either pole, the centrifugal force becomes less aligned with gravity as that force become perpendicular to centrifugal force which weakens in as a function of the cosign of the latitude as the diameter decreases. So it is a good thing it is not equal, it's in the wrong plane. But we are only talking about forces of around .5 % of the gravity. Dang! I wished you had not brought this up. @rasheedfan2005
