How fast does the earth need to rotate to realize 0 gravity?

[Midlander]

Originally posted by: YOyoYOhowsDAjello

Originally posted by: MercenaryForHire
http://liftoff.msfc.nasa.gov/academy/rocket_sci/orbmech/vel_calc.html 😛

To hold the lowest stable orbit of 185km above the Earth, you need a velocity of about 7.79km/second

- M4H

Wouldn't that only be the answer at the equator?

(so if you're not on the equator you're SOL since the earth would destroy itself before it got to a weightless condition anywhere else)

Good point! If you are standing at one of the poles, the earth's rotation would have no effect on the force of gravity. :beer:

 

[SoulAssassin]

I think the OP was high when he thought of this question. 🙂

 

[Toastedlightly]

This would only happen at the equator though. As you near the poles, the effect is far less (becoming nothing at the pole). This could be fun.

 

[YOyoYOhowsDAjello]

Originally posted by: Midlander

Originally posted by: YOyoYOhowsDAjello

Originally posted by: MercenaryForHire
http://liftoff.msfc.nasa.gov/academy/rocket_sci/orbmech/vel_calc.html 😛

To hold the lowest stable orbit of 185km above the Earth, you need a velocity of about 7.79km/second

- M4H

Wouldn't that only be the answer at the equator?

(so if you're not on the equator you're SOL since the earth would destroy itself before it got to a weightless condition anywhere else)

Good point! If you are standing at one of the poles, the earth's rotation would have no effect on the force of gravity. :beer:

You'd just slowly turn around (but faster than before 😀 )

 

[spidey07]

Originally posted by: Toastedlightly
This would only happen at the equator though. As you near the poles, the effect is far less (becoming nothing at the pole). This could be fun.

So it would stand to reason then that water could move towards the poles. Affect on the atmosphere? Surely wouldn't be good and the entire thing would be mucked up but it stands to reason there would be distinct bands of rotation more pronounced and radical than the current tropics.

I don't know much about orbit, but seems in essence what would happen at the equator - you're in orbit.

 

[YOyoYOhowsDAjello]

Originally posted by: spidey07

Originally posted by: Toastedlightly
This would only happen at the equator though. As you near the poles, the effect is far less (becoming nothing at the pole). This could be fun.

So it would stand to reason then that water could move towards the poles. Affect on the atmosphere? Surely wouldn't be good and the entire thing would be mucked up but it stands to reason there would be distinct bands of rotation more pronounced and radical than the current tropics.

I don't know much about orbit, but seems in essence what would happen at the equator - you're in orbit.

Seems like it would move away from the poles and towards the equator where the effect of gravity would be lessened so the weight of the "heavier" water at the poles would push water more to the "lighter" water at the equator.

The same thing would happen to the atmosphere.

 

[spidey07]

Originally posted by: YOyoYOhowsDAjello
Seems like it would move away from the poles and towards the equator where the effect of gravity would be lessened so the weight of the "heavier" water at the poles would push water more to the "lighter" water at the equator.

The same thing would happen to the atmosphere.

Convection.

Sorry for the one word post, but think about it.

 

[YOyoYOhowsDAjello]

Originally posted by: spidey07

Originally posted by: YOyoYOhowsDAjello
Seems like it would move away from the poles and towards the equator where the effect of gravity would be lessened so the weight of the "heavier" water at the poles would push water more to the "lighter" water at the equator.

The same thing would happen to the atmosphere.

Convection.

Sorry for the one word post, but think about it.

Are you thinking that heat has something to do with this?

I'm not sure what this has to do with the problem, care to add more words? 😛

 

[YOyoYOhowsDAjello]

Are you thinking the "band of air" in the middle would be moving faster and cause turbulance and convection type effects with the "bands" moving slower?

The Air wouldn't be moving any faster relative to the air next to it though, right? (Assuming we're not spinning the earth up really fast and give the water/air a chance to slowly get up to speed with the solid part)

Like now, the same thing would apply, but it's not happening since convection in the current atmosphere is temperature related, not the spinning of the earth.

 

[Toastedlightly]

Shouldn't this be in HT? 😛

 

[dighn]

Originally posted by: YOyoYOhowsDAjello

Seems like it would move away from the poles and towards the equator where the effect of gravity would be lessened so the weight of the "heavier" water at the poles would push water more to the "lighter" water at the equator.

The same thing would happen to the atmosphere.

I agree. if you add up the forces, the farther you get from the equator, the net force becomes more slanted towards the equater, so you should end up with a huge bulge of water belt at the equater and a wee bit of water at the poles

the atmosphere should just dissipate. an atmosphere of pressure + little to no gravity = poof

 

[spidey07]

Originally posted by: YOyoYOhowsDAjello
Are you thinking that heat has something to do with this?

I'm not sure what this has to do with the problem, care to add more words? 😛

Convection has to do with gravity, not heat.

I'm thinking that as the "heavier" water falls it it pushes the other water out and up towards the equator. Hence creating the disctinct rings I was speaking of. Reference the atmosphere of jupiter.

While were at it....how many distrinct convections/rings does Jupiter have?

 

[YOyoYOhowsDAjello]

Originally posted by: spidey07

Originally posted by: YOyoYOhowsDAjello
Are you thinking that heat has something to do with this?

I'm not sure what this has to do with the problem, care to add more words? 😛

Convection has to do with gravity, not heat.

I'm thinking that as the "heavier" water falls it it pushes the other water out and up towards the equator. Hence creating the disctinct rings I was speaking of. Reference the atmosphere of jupiter.

http://dictionary.reference.com/browse/convection

 

[50cent1228]

woah kool stuff

 

[spidey07]

Originally posted by: YOyoYOhowsDAjello
http://dictionary.reference.com/browse/convection

c'mon buddy....from your link:

"Physics
Heat transfer in a gas or liquid by the circulation of currents from one region to another.
Fluid motion caused by an external force such as gravity.
"

 

[YOyoYOhowsDAjello]

Originally posted by: dighn

Originally posted by: YOyoYOhowsDAjello

Seems like it would move away from the poles and towards the equator where the effect of gravity would be lessened so the weight of the "heavier" water at the poles would push water more to the "lighter" water at the equator.

The same thing would happen to the atmosphere.

I agree. if you add up the forces, the farther you get from the equator, the net force becomes more slanted towards the equater, so you should end up with a huge bulge of water belt at the equater and a wee bit of water at the poles

the atmosphere should just dissipate. an atmosphere of pressure + little to no gravity = poof

Yeah, the atmosphere would go first, but it seems like it would develop a bulge at the equator first and then escape from the earth gradually from a ring above the equator.

 

[YOyoYOhowsDAjello]

Originally posted by: spidey07

Originally posted by: YOyoYOhowsDAjello
http://dictionary.reference.com/browse/convection

c'mon buddy....from your link:

"Physics
Heat transfer in a gas or liquid by the circulation of currents from one region to another.
Fluid motion caused by an external force such as gravity.
"

I'm showing you why I thought you meant heat

(next time saying more than one word and "think about it" should clear up stuff like this 😉 )

"The interior of Jupiter is hot: the core is probably about 20,000 K. The heat is generated by the Kelvin-Helmholtz mechanism, the slow gravitational compression of the planet. (Jupiter does NOT produce energy by nuclear fusion as in the Sun; it is much too small and hence its interior is too cool to ignite nuclear reactions.) This interior heat probably causes convection deep within Jupiter's liquid layers and is probably responsible for the complex motions we see in the cloud tops."

http://seds.lpl.arizona.edu/nineplanets/nineplanets/jupiter.html

The rotation of Jupiter's polar atmosphere is ~5 minutes longer than that of the equatorial atmosphere

The planet Jupiter is primarily composed of hydrogen, with a smaller portion of helium and a rocky core. Due to its rapid rotation the planet possesses a slight but noticeable bulge around the equator, giving it an oblate appearance.

http://en.wikipedia.org/wiki/Jupiter

 

[spidey07]

Originally posted by: YOyoYOhowsDAjello
http://seds.lpl.arizona.edu/nineplanets/nineplanets/jupiter.html

Jupiter's polar atmosphere is ~5 minutes longer than that of the equatorial atmosphere

The planet Jupiter is primarily composed of hydrogen, with a smaller portion of helium and a rocky core. Due to its rapid rotation the planet possesses a slight but noticeable bulge around the equator, giving it an oblate appearance.

http://en.wikipedia.org/wiki/Jupiter

alright buddy....you got my drift. But our atmosphere is a lot "heavier" than her's. 😉

I still believe very distinct rings would form, similar to jupiter. The atmosphere would expand possibly turning us into a gas giant (nah, too close to the sun). Or at most a gas wanna be like venus as our mass could not really increase.

 

[YOyoYOhowsDAjello]

Originally posted by: spidey07

Originally posted by: YOyoYOhowsDAjello
http://seds.lpl.arizona.edu/nineplanets/nineplanets/jupiter.html

Jupiter's polar atmosphere is ~5 minutes longer than that of the equatorial atmosphere

The planet Jupiter is primarily composed of hydrogen, with a smaller portion of helium and a rocky core. Due to its rapid rotation the planet possesses a slight but noticeable bulge around the equator, giving it an oblate appearance.

http://en.wikipedia.org/wiki/Jupiter

alright buddy....you got my drift. But our atmosphere is a lot "heavier" than her's. 😉

I still believe very distinct rings would form, similar to jupiter. The atmosphere would expand possibly turning us into a gas giant (nah, too close to the sun). Or at most a gas wanna be like venus as our mass could not really increase.

Seems our atmosphere would just escape before we turned into anything like a gas giant. It would only expand at the equator anyway 😛

 

[spidey07]

Originally posted by: YOyoYOhowsDAjello
Seems our atmosphere would just escape before we turned into anything like a gas giant. It would only expand at the equator anyway 😛

Meh, look at our brother and sister.

BTW what is the period of Mars and Venus? Does anybody actually know the size of Jupiters core and does it even matter?

 

[YOyoYOhowsDAjello]

Originally posted by: spidey07

Originally posted by: YOyoYOhowsDAjello
Seems our atmosphere would just escape before we turned into anything like a gas giant. It would only expand at the equator anyway 😛

Meh, look at our brother and sister.

BTW what is the period of Mars and Venus? Does anybody actually know the size of Jupiters core and does it even matter?

I don't understand what Mars and Venus have to do with this unless you have a plan to spin them up as a test before you try it on the earth 😀

Mars:
Sidereal rotation period: 1.025 957 d
(24.622 962 h)
Rotation velocity at equator: 868.22 km/h (539.49 mi/h)

Venus:
Sidereal rotation period: -243.0185 d
Rotation velocity at equator: 6.52 km/h (at the equator)

http://www2.jpl.nasa.gov/galileo/jupiter/core.html ?

 

[dighn]

Jupiter is pretty different from the scenario discussed in this thread. Although its rotation is quite fast, the acceleration at equator is just a fraction of its gravity (~10%).

 

[YOyoYOhowsDAjello]

Originally posted by: dighn
Jupiter is pretty different from the scenario discussed in this thread. Although its rotation is quite fast, the acceleration at equator is just a fraction of its gravity (~10%).

Yeah, I'm just posting crap about it since

Originally posted by: spidey07

I'm thinking that as the "heavier" water falls it it pushes the other water out and up towards the equator. Hence creating the disctinct rings I was speaking of. Reference the atmosphere of jupiter.

While were at it....how many distrinct convections/rings does Jupiter have?

 

[dighn]

sorry I wasn't being clear. I was actually agreeing with you 😛

anyway what am I doing here, I have work to do 😛

 

[spidey07]

Originally posted by: YOyoYOhowsDAjello
http://www2.jpl.nasa.gov/galileo/jupiter/core.html ?

So basically we have no freaking clue what jupiter composition is?

Me? I wanna visit Neptune. That's a cool freakin' place. Storms, blackhole drive, people coming back from said blackhole drive being psychos. Good stuff. Maybe they should make a movie out of it....kinda a sci-fi horrer flick.