# The Naked Scientists Forum

### Author Topic: How would you induce a spin into a planet?  (Read 9839 times)

#### CliffordK

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##### How would you induce a spin into a planet?
« on: 27/08/2012 22:34:46 »
Say...
One had a planet slightly smaller than Earth, with a thick atmosphere, but it had a rotational period of about 243 days.

How would one increase the rate of spin (decrease the length of day) down to about a 24 hour day?

One option might be to attach some huge jet engines or rocket engines to the surface, and let them blast away at the atmosphere.  Would this have any net effect as the wind would spin a bit, but would eventually stop.  So, logically it might not have a permanent effect on the planetary rotational speed once the engines were stopped.

Perhaps selectively bombard the planet with eastward, or westward (depending on preference) asteroids and comets.  But, that might be like trying to move a truck with a BB gun.  One would need a lot of BBs.

Other ideas?

#### bizerl

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##### Re: How would you induce a spin into a planet?
« Reply #1 on: 27/08/2012 23:38:04 »
Could a large, low-orbit object do much? Sort of like the opposite to a gravitational slingshot?

#### CPT ArkAngel

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##### Re: How would you induce a spin into a planet?
« Reply #2 on: 28/08/2012 00:10:27 »
Clifford, your first example is not correct because your jet engines would produce an opposite force on the ground (action=reaction). The best way would probably be to fire cannon balls at low angles and at a higher speed than escape velocity.

#### William McCormick

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##### Re: How would you induce a spin into a planet?
« Reply #3 on: 28/08/2012 02:14:33 »
Say...
One had a planet slightly smaller than Earth, with a thick atmosphere, but it had a rotational period of about 243 days.

How would one increase the rate of spin (decrease the length of day) down to about a 24 hour day?

One option might be to attach some huge jet engines or rocket engines to the surface, and let them blast away at the atmosphere.  Would this have any net effect as the wind would spin a bit, but would eventually stop.  So, logically it might not have a permanent effect on the planetary rotational speed once the engines were stopped.

Perhaps selectively bombard the planet with eastward, or westward (depending on preference) asteroids and comets.  But, that might be like trying to move a truck with a BB gun.  One would need a lot of BBs.

Other ideas?

Increase (meant decrease) the amount of liquid in the core. You have probably done this experiment, my Aunt Carole showed me this one. If you spin a hard boiled egg and then try to spin a soft boiled egg, and then a raw egg. You will see what might be a factor in the speed of rotation. You can just do the hard boiled egg and raw egg, it is a very impressive demonstration.

Personally I believe the sun rotates, and causes planets to rotate. Much like hematite magnets will mimic each other, if one of them is spun. The other magnet starts to spin too.

Sincerely,

William McCormick

« Last Edit: 28/08/2012 05:17:23 by William McCormick »

#### William McCormick

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##### Re: How would you induce a spin into a planet?
« Reply #4 on: 28/08/2012 03:07:23 »
Clifford, your first example is not correct because your jet engines would produce an opposite force on the ground (action=reaction). The best way would probably be to fire cannon balls at low angles and at a higher speed than escape velocity.

Imagine you put giant get engines on the Ronald Reagan aircraft carrier. You turn them on and the ship goes forward at 100 knots. Is the ocean that the ship is cutting through now, somehow pushing on the planet in the direction of the ships travel. I say no.

I believe and so did some engineers of the past, that jet engines mounted to the ground, or even large motors and propellers could put force upon the earth, force that would not have a counter force upon the earth through the air. The air has no way to transmit the force back to the earth. Just like the ocean would not be able to transmit the energy from a giant propeller mounted, on a oil rig back to the earth through the water. Gravity would be the force that presses and equalized the air or water pressure. It would not have to be the surface of the earth.

Air and water both have the ability to divert energy, while not absorbing and transmitting it in the same direction it was received.

Take a look at this.

It is so much cooler to learn this in a pool hall. With a tight and loose rack of billiard balls, when you try to break up each, the loose and the tight rack. It is almost unbelievable to see the difference. How the loose rack absorbs the energy. And the tight rack transmits it rather violently.

Sincerely,

William McCormick

#### CliffordK

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##### Re: How would you induce a spin into a planet?
« Reply #5 on: 28/08/2012 06:53:02 »
It would be a monumental task to cool the core of a planet, and may not produce the desired output, as a spinning planetary core may help produce a magnetic field that would protect the planet form solar wind and cosmic rays.

There are theories that much of the motion of the planets is due to the spinning of matter in the protoplanetary disk around the early sun.  The two innermost planets (Mercury and Venus) have the slowest rotation so it seems unlikely that the rotation of the sun is powering the rotation of the planets.  Also consider our moon is tidally locked with the Earth, rather than being spun by the Earth.

As far as just pushing on the atmosphere, the reason I don't think it would work is this.

Consider lobbing cannon balls the length of a football field.  When you fire them off, they would impart a slight acceleration to the planet.  However, when they land, they would impart a negative acceleration to the planet, and the net would be zero acceleration.

I think I wrote this earlier in a similar topic.  Consider if you were in a closed school bus with perfect bearings.  And you had a pile of shot-puts at the front of the bus, so you would pick up the shots and throw them at the back of the bus.  The bus might lurch forward slightly when you throw the shot-put, but then it would stop again when it slammed into the back of the bus.  And, in fact, carrying the shot-puts back to the front of the bus to try again might erase all progress that was made.  Likewise, a fan inside the bus with all the windows closed would be ineffective in moving it.

So, blowing in the atmosphere, or using a propeller in an ocean would be ineffective if the planet slowed or dissipated the movement.

The best way would probably be to fire cannon balls at low angles and at a higher speed than escape velocity.

One would have to contend with the atmosphere when firing the cannon balls, unless perhaps one would first condense the atmosphere, then fire the cannon balls in a thin atmosphere.

If you could fire the cannon balls around the sun, then allowed them to impact the planet on the opposite side, one might be able to conserve mass and maximize the energy gain.  Although, perhaps the overall quantity of matter needed to start the planet, or the planet's crust spinning would be relatively minimal.

Could a large, low-orbit object do much? Sort of like the opposite to a gravitational slingshot?

Using tidal forces alone to start a planet spinning would be an excruciatingly slow process, and might take billions of years.

Rather than slingshotting around the sun, one might be able to fire a rocket, slingshot around the moon, and impact the planet in the opposite direction, slowly converting rotational momentum of the planet to orbital velocity of the moon.

Too small of a moon, and one would send the moon speeding too fast.

Of course, if the planet did not have a moon, one would have to be captured.

#### bizerl

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##### Re: How would you induce a spin into a planet?
« Reply #6 on: 28/08/2012 07:53:13 »
Say...
One had a planet slightly smaller than Earth, with a thick atmosphere, but it had a rotational period of about 243 days.

How would one increase the rate of spin (decrease the length of day) down to about a 24 hour day?

One option might be to attach some huge jet engines or rocket engines to the surface, and let them blast away at the atmosphere.  Would this have any net effect as the wind would spin a bit, but would eventually stop.  So, logically it might not have a permanent effect on the planetary rotational speed once the engines were stopped.

Perhaps selectively bombard the planet with eastward, or westward (depending on preference) asteroids and comets.  But, that might be like trying to move a truck with a BB gun.  One would need a lot of BBs.

Other ideas?

CliffordK, are you some sort of inter-planetary adventurer that requires this information to save your homeworld? It seems like a very specific problem you have posed.

When I think of how planetary spin is affected, generally it is slowed rather than speeded up. I wonder if there are any cases where a planet's rotation has speeded up since it formed, or whether all planetary bodies are destined to gradually slow down to a halt.

I believe stars have the ability to speed up as they collapse, but I guess that if you had the capacity to collapse a planet enough to affect rotation, you probably wouldn't need to.

I think you need Superman.

If you are not him already...

has anyone ever seen CliffordK and Superman in the same room together?

#### CliffordK

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##### Re: How would you induce a spin into a planet?
« Reply #7 on: 28/08/2012 11:33:16 »
CliffordK, are you some sort of inter-planetary adventurer that requires this information to save your homeworld? It seems like a very specific problem you have posed.

Ok,
Yes, somewhat specific.

There has been a lot of buzz about Mars lately.

It is my belief that while we might eventually be able to colonize Mars, it will never be like "home", and we might not ever be able to venture outside without space suits and enclosed vehicles.

Certainly there are some advantages of a Martian colony over other planets and moons as the peak daytime temperatures are almost liveable, and it has a good length of a day.

However, I believe that Venus could actually eventually be terraformed into Earth 2.0, and truly support an earth-like environment, far more than Mars is capable of doing.  It would certainly take engineering that would tax humanity to the limit.  It would take a planet sized heat shield....  which would have to be maintained in working order forever. and there may also be a hydrogen deficit on the planet which would have to be dealt with.

Gravity would be similar to what we've evolved with on Earth, and it should be able to support a pressurized, breathable atmosphere.

I've seen proposals that the planet be cooled and the CO2 precipitated out of the atmosphere.  Presumably it would then be entombed, and slowly released as needed for the growth of plant matter.

One of the issues though is that the days are 243 days long...  I.E.  dark for 120 days, and light for 120 days.

What I realized as I was thinking about it a couple of days ago is that pushing on the atmosphere would not be sufficient to speed up the planetary rotation.  It would require essentially loosing matter to space (or as I suggested above, a slingshot around the sun or another object to preserve the matter).

Perhaps the solution would be to make an artificial sun that would orbit around the planet rather than speeding up the planetary rotation.  Ok, well not exactly a sun, but if one is building enormous heat shields, one could potentially also build a mirror that would redirect some of the sunlight to the areas of the planet where one wanted daylight.

In fact, with a well designed primary mirror in the L1 Lagrange point, the secondary mirror orbiting the planet could be substantially smaller.

has anyone ever seen CliffordK and Superman in the same room together?

I did have a friend once who commented that my initials were "CK".

#### imatfaal

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##### Re: How would you induce a spin into a planet?
« Reply #8 on: 28/08/2012 17:17:59 »
Clifford - the energy requirement can be more easily worked out

Rotational Kinetic Energy

For a sphere the moment of inertia of a symmetric axis

For Venus the angular velocity would be

For New Venus

Calculating the difference of the energy with the two difference angular velocities I get an answer of 3*10^33 Joules.  At 2008 consumptions that's about a million million years worth of our energy consumption.  Or about 100 days of total solar energy production - if we can muck around with that sort of energy we won't need to be bothering with terraforming venus
« Last Edit: 28/08/2012 17:26:28 by imatfaal »

#### CliffordK

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##### Re: How would you induce a spin into a planet?
« Reply #9 on: 28/08/2012 19:51:01 »
Thanks.

Certainly one could do the process over time...  Perhaps a century or two?  Maybe even a couple of millennia.  Can humans plan that far ahead?  But a million years would be a long time to wait, especially if there was a process such as asteroid impacts that was potentially damaging to the planet.  One might look at the total amount of sunlight striking the planet, then take a portion of that as the energy one had available to "spin" the planet.

If one chose to develop artificial sunlight with a mirror orbiting the planet, then one could be very slow with changing the planet's spin.

The Japan Earthquake was supposed to have shortened the day on Earth (made Earth spin faster) by about 1.8 microseconds.  Could a  million such earthquakes shorten the day by 1 to 2 seconds?

I suppose another way to look at time.  With all the effort we've been putting into increasing the amount of CO2 in Earth's atmosphere, we've only successfully increased the CO2 by about 100 ppm in (0.01% of the
total atmosphere).  Reducing the CO2 in Venus' atmosphere should be quick by shielding the sun and cooling the planet to below to  -78 °C,  (-109 °F) to precipitate out the CO2 (assuming we could then store it somehow).  But, then it could take quite some time to build up 1.3 x 1014 tons of oxygen in the atmosphere.

How much solar energy striking the planet would it take to convert CO2 to 1.3 x 1014 tons of O2?

#### William McCormick

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##### Re: How would you induce a spin into a planet?
« Reply #10 on: 30/08/2012 01:35:54 »
It would be a monumental task to cool the core of a planet, and may not produce the desired output, as a spinning planetary core may help produce a magnetic field that would protect the planet form solar wind and cosmic rays.

There are theories that much of the motion of the planets is due to the spinning of matter in the protoplanetary disk around the early sun.  The two innermost planets (Mercury and Venus) have the slowest rotation so it seems unlikely that the rotation of the sun is powering the rotation of the planets.  Also consider our moon is tidally locked with the Earth, rather than being spun by the Earth.

As far as just pushing on the atmosphere, the reason I don't think it would work is this.

Consider lobbing cannon balls the length of a football field.  When you fire them off, they would impart a slight acceleration to the planet.  However, when they land, they would impart a negative acceleration to the planet, and the net would be zero acceleration.

I think I wrote this earlier in a similar topic.  Consider if you were in a closed school bus with perfect bearings.  And you had a pile of shot-puts at the front of the bus, so you would pick up the shots and throw them at the back of the bus.  The bus might lurch forward slightly when you throw the shot-put, but then it would stop again when it slammed into the back of the bus.  And, in fact, carrying the shot-puts back to the front of the bus to try again might erase all progress that was made.  Likewise, a fan inside the bus with all the windows closed would be ineffective in moving it.

So, blowing in the atmosphere, or using a propeller in an ocean would be ineffective if the planet slowed or dissipated the movement.

The best way would probably be to fire cannon balls at low angles and at a higher speed than escape velocity.

One would have to contend with the atmosphere when firing the cannon balls, unless perhaps one would first condense the atmosphere, then fire the cannon balls in a thin atmosphere.

If you could fire the cannon balls around the sun, then allowed them to impact the planet on the opposite side, one might be able to conserve mass and maximize the energy gain.  Although, perhaps the overall quantity of matter needed to start the planet, or the planet's crust spinning would be relatively minimal.

Could a large, low-orbit object do much? Sort of like the opposite to a gravitational slingshot?

Using tidal forces alone to start a planet spinning would be an excruciatingly slow process, and might take billions of years.

Rather than slingshotting around the sun, one might be able to fire a rocket, slingshot around the moon, and impact the planet in the opposite direction, slowly converting rotational momentum of the planet to orbital velocity of the moon.

Too small of a moon, and one would send the moon speeding too fast.

Of course, if the planet did not have a moon, one would have to be captured.

You have seen the bent muskets, turned 90 degrees, it is well known that turning an object using a 90 degree arc, does not use all or even much of the energy, of a projectile. So if you fired a cannon with a 90 arced barrel that sent it straight up. You would have your method for propelling the earth with a cannon or gun.

That same arced path, is the reason air and water, can accomplish the task, at hand. It sends energy off in arced paths. The arced musket recoils nicely.

You guys should get out in the field, and out of the tainted books.

Conservation of energy, is like, a lobotomy.

Sincerely,

William McCormick

#### William McCormick

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##### Re: How would you induce a spin into a planet?
« Reply #11 on: 30/08/2012 01:44:23 »
It would be a monumental task to cool the core of a planet, and may not produce the desired output, as a spinning planetary core may help produce a magnetic field that would protect the planet form solar wind and cosmic rays.

There are theories that much of the motion of the planets is due to the spinning of matter in the protoplanetary disk around the early sun.  The two innermost planets (Mercury and Venus) have the slowest rotation so it seems unlikely that the rotation of the sun is powering the rotation of the planets.  Also consider our moon is tidally locked with the Earth, rather than being spun by the Earth.

As far as just pushing on the atmosphere, the reason I don't think it would work is this.

Consider lobbing cannon balls the length of a football field.  When you fire them off, they would impart a slight acceleration to the planet.  However, when they land, they would impart a negative acceleration to the planet, and the net would be zero acceleration.

I think I wrote this earlier in a similar topic.  Consider if you were in a closed school bus with perfect bearings.  And you had a pile of shot-puts at the front of the bus, so you would pick up the shots and throw them at the back of the bus.  The bus might lurch forward slightly when you throw the shot-put, but then it would stop again when it slammed into the back of the bus.  And, in fact, carrying the shot-puts back to the front of the bus to try again might erase all progress that was made.  Likewise, a fan inside the bus with all the windows closed would be ineffective in moving it.

So, blowing in the atmosphere, or using a propeller in an ocean would be ineffective if the planet slowed or dissipated the movement.

The best way would probably be to fire cannon balls at low angles and at a higher speed than escape velocity.

One would have to contend with the atmosphere when firing the cannon balls, unless perhaps one would first condense the atmosphere, then fire the cannon balls in a thin atmosphere.

If you could fire the cannon balls around the sun, then allowed them to impact the planet on the opposite side, one might be able to conserve mass and maximize the energy gain.  Although, perhaps the overall quantity of matter needed to start the planet, or the planet's crust spinning would be relatively minimal.

Could a large, low-orbit object do much? Sort of like the opposite to a gravitational slingshot?

Using tidal forces alone to start a planet spinning would be an excruciatingly slow process, and might take billions of years.

Rather than slingshotting around the sun, one might be able to fire a rocket, slingshot around the moon, and impact the planet in the opposite direction, slowly converting rotational momentum of the planet to orbital velocity of the moon.

Too small of a moon, and one would send the moon speeding too fast.

Of course, if the planet did not have a moon, one would have to be captured.

You could also just fire the cannon ball into a loosely packed set of cannon balls. Instead of one cannon ball, going several hundred yards or a mile. Ten cannon balls might only move twenty feet.

Sincerely,

William McCormick

#### William McCormick

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##### Re: How would you induce a spin into a planet?
« Reply #12 on: 30/08/2012 02:04:36 »
It would be a monumental task to cool the core of a planet, and may not produce the desired output, as a spinning planetary core may help produce a magnetic field that would protect the planet form solar wind and cosmic rays.

There are theories that much of the motion of the planets is due to the spinning of matter in the protoplanetary disk around the early sun.  The two innermost planets (Mercury and Venus) have the slowest rotation so it seems unlikely that the rotation of the sun is powering the rotation of the planets.  Also consider our moon is tidally locked with the Earth, rather than being spun by the Earth.

As far as just pushing on the atmosphere, the reason I don't think it would work is this.

Consider lobbing cannon balls the length of a football field.  When you fire them off, they would impart a slight acceleration to the planet.  However, when they land, they would impart a negative acceleration to the planet, and the net would be zero acceleration.

I think I wrote this earlier in a similar topic.  Consider if you were in a closed school bus with perfect bearings.  And you had a pile of shot-puts at the front of the bus, so you would pick up the shots and throw them at the back of the bus.  The bus might lurch forward slightly when you throw the shot-put, but then it would stop again when it slammed into the back of the bus.  And, in fact, carrying the shot-puts back to the front of the bus to try again might erase all progress that was made.  Likewise, a fan inside the bus with all the windows closed would be ineffective in moving it.

So, blowing in the atmosphere, or using a propeller in an ocean would be ineffective if the planet slowed or dissipated the movement.

The best way would probably be to fire cannon balls at low angles and at a higher speed than escape velocity.

One would have to contend with the atmosphere when firing the cannon balls, unless perhaps one would first condense the atmosphere, then fire the cannon balls in a thin atmosphere.

If you could fire the cannon balls around the sun, then allowed them to impact the planet on the opposite side, one might be able to conserve mass and maximize the energy gain.  Although, perhaps the overall quantity of matter needed to start the planet, or the planet's crust spinning would be relatively minimal.

Could a large, low-orbit object do much? Sort of like the opposite to a gravitational slingshot?

Using tidal forces alone to start a planet spinning would be an excruciatingly slow process, and might take billions of years.

Rather than slingshotting around the sun, one might be able to fire a rocket, slingshot around the moon, and impact the planet in the opposite direction, slowly converting rotational momentum of the planet to orbital velocity of the moon.

Too small of a moon, and one would send the moon speeding too fast.

Of course, if the planet did not have a moon, one would have to be captured.

Look at Niagara Falls. There is a constant pressure on the earth in the opposite direction of the falls themselves. Gravity pushes the water down to the bottom, after the falls leave the cliff, not the air.

So you could also put a giant pump on a oil rig, and pump water in one direction, horizontally to the surface of the earth, up high enough, so that it falls vertically when it hits the ocean. By letting gravity push the water, down into the ocean. So the air, has no force applied to it.

I do not believe that the ocean can communicate the force to the earth anyway, but Iincluded it, just to show I thought of it.

Sincerely,

William McCormick

#### damocles

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##### Re: How would you induce a spin into a planet?
« Reply #13 on: 30/08/2012 07:55:02 »
With effects like several of those discussed in this thread -- firing of cannon, cycling of water at different elevations, etc. -- it is possible to alter a planet's angular orientation, but not its angular momentum. Angular momentum of a system must be conserved. So must energy. The angular velocity of the Earth  is gradually decreasing all the time (length of day increasing) because of tidal friction (moon and sun) causing heating. The angular momentum is conserved by the moon moving slowly further away from the Earth, and the Earth's orbit moving slowly away from the sun.

It is quite easy to work out the angular momentum of a planet, and the amount of angular kinetic energy that would be needed to reduce it to near zero. That would be a useful thing to do for the Earth, because the Earth and Venus are near-twin planets in terms of size and density (the most recent measurements suggest that Venus is almost exactly the same size as the Earth, but about 10% less dense. So if we calculate the angular kinetic energy of the Earth's rotation, then that will be about 10% larger than the amount of kinetic energy it would take -- applied kinetically as a tangential couple -- to speed up Venus' rotation to a similar rate to the Earth's.

The Earth's kinetic energy of rotation is, according to this website -- qntm.org/data -- 2.5786 E29 J

World annual energy consumption is, according to wikipedia -- en.wikipedia.org/wiki/World_energy_consumption -- 4.74 E20 J

This means that the energy that would have to be invested to speed up the rotation of Venus, if it could be applied efficiently, would correspond to 400 million years of the world's current total energy consumption. And unfortunately, the two conservation laws -- angular momentum and total energy -- are set in stone.
« Last Edit: 30/08/2012 14:08:19 by damocles »

#### William McCormick

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##### Re: How would you induce a spin into a planet?
« Reply #14 on: 02/09/2012 22:43:15 »
With effects like several of those discussed in this thread -- firing of cannon, cycling of water at different elevations, etc. -- it is possible to alter a planet's angular orientation, but not its angular momentum. Angular momentum of a system must be conserved. So must energy. The angular velocity of the Earth  is gradually decreasing all the time (length of day increasing) because of tidal friction (moon and sun) causing heating. The angular momentum is conserved by the moon moving slowly further away from the Earth, and the Earth's orbit moving slowly away from the sun.

It is quite easy to work out the angular momentum of a planet, and the amount of angular kinetic energy that would be needed to reduce it to near zero. That would be a useful thing to do for the Earth, because the Earth and Venus are near-twin planets in terms of size and density (the most recent measurements suggest that Venus is almost exactly the same size as the Earth, but about 10% less dense. So if we calculate the angular kinetic energy of the Earth's rotation, then that will be about 10% larger than the amount of kinetic energy it would take -- applied kinetically as a tangential couple -- to speed up Venus' rotation to a similar rate to the Earth's.

The Earth's kinetic energy of rotation is, according to this website -- qntm.org/data -- 2.5786 E29 J

World annual energy consumption is, according to wikipedia -- en.wikipedia.org/wiki/World_energy_consumption -- 4.74 E20 J

This means that the energy that would have to be invested to speed up the rotation of Venus, if it could be applied efficiently, would correspond to 400 million years of the world's current total energy consumption. And unfortunately, the two conservation laws -- angular momentum and total energy -- are set in stone.

With a small magnetic field over the earth you can spin it up or slow it down. Bend it twist it hurl it, you name it. It is purely a mass of particles of electricity. I see now why most people do not know this, they do not wish to know where they are.

The power that keeps the earth created, comes not from within, but from beyond.

Sincerely,

William McCormick

#### damocles

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##### Re: How would you induce a spin into a planet?
« Reply #15 on: 02/09/2012 23:21:29 »
From William:
Quote
With a small magnetic field over the earth you can spin it up or slow it down.
No, William, you cannot. Neither the great Benjamin Franklin nor the great Nikola Tesla ever achieved this. There has been no change in the earth's rotation other than a steady increase in day length of the order of 2 milliseconds per century. There has been no report of any human tampering affecting the length of day (other than the prayers of Joshua and King Hezekiah). Over the last two centuries the Royal Greenwich Observatory (among other institutions) has been carefully monitoring the length of sidereal day (solar day does vary in a regular seasonal fashion), and observed no departure from the regular pattern in spite of significant variation in the Earth's magnetic field, and in external magnetic fields affecting the Earth.
Variations in the Earth's magnetic field have been observed in the wandering of the magnetic poles and in quite significant changes in field strength. Variations in external magnetic fields occur with swarms of charged particles from solar storms passing the Earth.

#### William McCormick

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##### Re: How would you induce a spin into a planet?
« Reply #16 on: 03/09/2012 02:21:02 »
From William:
Quote
Neither the great Benjamin Franklin nor the great Nikola Tesla ever achieved this. There has been no change in the earth's rotation other than a steady increase in day length of the order of 2 milliseconds per century. There has been no report of any human tampering affecting the length of day (other than the prayers of Joshua and King Hezekiah). Over the last two centuries the Royal Greenwich Observatory (among other institutions) has been carefully monitoring the length of sidereal day (solar day does vary in a regular seasonal fashion), and observed no departure from the regular pattern in spite of significant variation in the Earth's magnetic field, and in external magnetic fields affecting the Earth.
Variations in the Earth's magnetic field have been observed in the wandering of the magnetic poles and in quite significant changes in field strength. Variations in external magnetic fields occur with swarms of charged particles from solar storms passing the Earth.

That is because they were not lunatics, and cowards like many of the "modern scientists", just itching to push the button on something new and unknown to them. Which is just about everything around them.

The earth is propelled by external forces, it is created and kept in creation by external forces. As you make metal thinner or smaller in diameter. It starts to lose some of its tenacity. Look at the edge of very thin metal under a microscope, it is no longer, that smooth hard metal surface, it is more like a ceramic or glass. Very brittle and uneven.

That would not be the case if, as "modern scientists" claim that the strength of attraction was from the inside. In fact everything is under pressure, from ambient radiation from outside the object. So as things get smaller, there is less time for ambient radiation entering on the far side of the object to positively accelerate, which would leave a vacuum, or shortage of particles of electricity in the object.  As soon as the ambient radiation enters the thin objectat reduced speed, it is suddenly leaving to a place that is equally abundant with particles of electricity. Causing a certain amount of repulsion, because of a bottle neck or buildup of partices of electricity.

If we take a low velocity 45 caliber round, we can blow a hole in a 1/16" plate with ease. It makes a perfect hole and you can reclaim the round, it is still in good condition. If though we take the same round at the same velocity and fire it at a 3/16" plate of the same material, the round smashes and turns to dust, on the surface. It will not even remove the paint that is on the surface of the 3/16" metal. Where on the 1/16" plate it goes right through. It is all about the surface of the metal being able to create a counter force, of electromotive force. The thin plate was unable to create the conductance necessary to maintain a shortage of particles of electricity in the plate. Once there was an abundance of particles of electricity in the metal itself, the material is as easy to penetrate as liquid.

The thicker material is able to create an ARC ray powerful enough to destroy the round. Basically turn the round into a liquid that does not have enough capacitance to destroy the metal it is striking.

If any of you saw the 9/11 video of the plane striking one of the towers, you may have seen the ARC ray in front of the plane, and a smaller ARC ray, coming off the building. The plane won and cut right through steel "H" beams. Even though it was aluminum, at reduced speeds it could never happen. It is just an electrical effect. Much like a plasma cutter.

We know that at a stand still, it requires hundreds or thousands of times more energy, to put holes in objects, that bullets put holes in with ease, and with very little actual force. It is just an electrical effect.

There is almost no force from a bullet. When you see guys with bullet proof vests, flying around, that is the movies. You might not even know you were hit by a rifle round if you were wearing the correct body armor.  The bullet is basically a plasma cutter. Since a plasma cutter cuts through just about anything it is pretty effective.

The lunar module used a special magnetic field, to connect high velocity objects like meteorites, electrically, with the Lunar module to take away any advantage of the moving object. This was all well known and has been taken away from the public for the most part.

Sincerely,

William McCormick

« Last Edit: 03/09/2012 04:00:41 by William McCormick »

#### William McCormick

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##### Re: How would you induce a spin into a planet?
« Reply #17 on: 03/09/2012 02:43:02 »
If you stand in water, and hold a well insulated, high frequency TIG, electrode, in your hand. You will be pushed around as if there are ten people around you pushing you back and forth. In all directions, from 360 degrees around you.

Now I noted that there was no air pressure increase I could feel on my face. And would have certainly felt any wind powerful enough to do that to me. So the effect is purely an electrical effect.

I was trained by special trainers to deal with disasters which come from handling chemicals. We were being shown a video of how to prepare to deal with anhydrous ammonia spills. We were already pretty well trained and we were laughing a bit. I had already known that on a farm now and then a farm animal will be thrown a good distance by an ammonia and methane explosion. My father taught me about the danger when I was a kid. He said the explosion was silent.

Well I was joking around and the trainer knuckled me on the back of my head and said to pay attention, it nearly took the life of one of his men to make the video. The guys in the video went in to clean up the anhydrous ammonia spill. The first thing to do, was to move the forklift truck out of the spill. When the fellow went to start the forklift, the camera man dropped the camera. But there was no visible or audible explosion, no paper or stuff on the benches moved or blown around. However when the fellow picked up the camera and panned the room, they were short one man. He was positively accelerated to a speed that blew him right through a cinder block wall. It was truly fascinating to see. There is no way the over pressure needed to move the man at that velocity could have been created without, destroying a lot of things in that room. The forklift driver did not even know what happened. That is how quiet it was.

Sincerely,

William McCormick

#### damocles

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##### Re: How would you induce a spin into a planet?
« Reply #18 on: 03/09/2012 08:15:42 »
And all of this has nothing to do with the fact that "a small magnetic field all over the Earth" can not "spin up" nor "slow down" the earth, as has been amply demonstrated by the fact that the earth has been subjected to a range of natural variations in both its own magnetic field and external magnetic fields it has been exposed to, without showing the slightest inclination to "spin up" or "slow down", quite apart from the fact that there is no mechanism known to science whereby this might be achieved, quite apart from the fact that the huge kinetic energy associated with the earth's rotation could not conceivably be altered by the energy cheap process of applying "a small magnetic field all over the Earth".

William is obviously very impressed with electricity and explosions and arcs and other such phenomena, but his idea of "science" is a long way out beyond the orbit of the moon!

#### CliffordK

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##### Re: How would you induce a spin into a planet?
« Reply #19 on: 03/09/2012 17:36:02 »
I had asked about introducing "spin" to a planet such as Venus.

Off-topic discussions about rifle rounds and bullet proof vests have been moved here

------------------------------------------

Thanks imatfaal & damocles for your calculations.
A thousand year task might be worth considering if other parts of the planet terraforming and colonization could occur simultaneously.
A million year task is probably beyond what we could attempt, especially if it was highly resource intensive.
And, a half a billion year task likely wouldn't be worth initiating as it would be a good fraction of the expected lifespan of our sun.

Another option might be to move a asteroid such as Ceres into an elliptical planet crossing orbit, and force it to crash into Venus at the appropriate place and angle.  Of course, the risk is that if a large asteroid from beyond Earth is moved into a Venus crossing orbit, it would also be in an Earth crossing orbit.

Could I gain enough energy by merely changing the eccentricity of one or more asteroid orbits?

No doubt some of the physicists here will tell me that it is too much energy alter the eccentricity of orbit of a large asteroid or dwarf planet into a Venus crossing orbit.  Or, that a tangential impact of Ceres would not be enough to make a 24 hour day.

And, of course, we would have to be far more advanced than we are today to convince any government to allow one to move an potentially planet killing asteroid into an Earth crossing orbit, especially if it would be a multi-generational project.

Oh...

From wikipedia.  Ceres is the dot below the moon on the bottom left.  I suppose it would take all the energy we could muster to move it into a Venus crossing orbit, and it would be like shooting a BB at the planet.
« Last Edit: 03/09/2012 19:56:29 by CliffordK »

#### damocles

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##### Re: How would you induce a spin into a planet?
« Reply #20 on: 03/09/2012 23:53:08 »
From CliffordK:
Quote
Another option might be to move a asteroid such as Ceres into an elliptical planet crossing orbit, and force it to crash into Venus at the appropriate place and angle.  Of course, the risk is that if a large asteroid from beyond Earth is moved into a Venus crossing orbit, it would also be in an Earth crossing orbit.

Could I gain enough energy by merely changing the eccentricity of one or more asteroid orbits?

No doubt some of the physicists here will tell me that it is too much energy alter the eccentricity of orbit of a large asteroid or dwarf planet into a Venus crossing orbit.  Or, that a tangential impact of Ceres would not be enough to make a 24 hour day.

And, of course, we would have to be far more advanced than we are today to convince any government to allow one to move an potentially planet killing asteroid into an Earth crossing orbit, especially if it would be a multi-generational project.

The good news: there would be no need to artificially accelerate Ceres into a Venus-crossing orbit: the lower energy requirement of an Earth-tangential orbit would be quite enough -- an Earth gravity whip would be enough both to increase its kinetic energy and to put it into a Venus-crossing orbit.

The bad news: such a project would be even less palatable to politically sensitive Earth-bound governments.

The really bad news: It is almost certain that our technology-based civilization will not last more than another century or two. Projects that assume some sort of coherent cultural continuity over a period of thousands (let alone millions) of years are really dreamland scenarios. I remember reading, back in the 1970s, an article that did a deep and very convincing analysis of "civilizations" (= great empires with a semi-urban basis and a cultural continuity). The conclusion was that the average lifetime of a "civilization" was around 800 years, with the longest that had yet been achieved being the Egyptian, at about 3500 years. We are facing challenges of sustainable living that our society just does not have the tools to address: population, soil degradation, freshwater supply degradation, climate change, etc. According to the criteria in the article I have referred to, we would have to recognize our present "civilization" as having its origins with the Renaissance in the 16th century, and to recognize that more than half of the world's population has only a marginal share in it.

Anyway, away from sociology politics and back to physics. I had been trying to work out what sort of collision with Venus would lead to maximum transfer of rotational angular momentum. A direct hit would transfer only orbital angular momentum, and no rotational. A tangential hit would impart some rotational angular momentum to Venus, but there would be a substantial "splash" that would carry some material away from Venus with a sizeable orbital angular momentum. I have come to the tentative conclusion that a gravity whip that would accelerate Ceres into a highly eccentric orbit with a direct splashdown into the sun might be optimal.

Some more good news: Orbital angular momenta are very much greater than rotational angular momenta. It is quite conceivable that an efficient transfer of orbital angular momentum, even from a light body like Ceres, could make a relatively large difference to the rotational angular momentum of a large planet like Venus.

Some more bad news: ... but that also means that it might take rather more energy than we would like to spend to accelerate Ceres into an Earth-tangential orbit. Perhaps a huge solar sail??

#### CliffordK

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##### Re: How would you induce a spin into a planet?
« Reply #21 on: 04/09/2012 04:51:00 »
I like the idea of using Earth as a gravity assist.

The propulsion would have to be made on Ceres, either a solar sail from Ceres, or a solar powered plasma engine, or both.  The solar sail, of course, would be mass conserving, but would need to be made HUGE  It would also require stabilizing Ceres's rotation.  The plasma engine would be mass wasting, but several could be coupled to deal with the rotation of the dwarf planet.

For simplicity, one could assume that the average orbit remains constant, and only the eccentricity changes.  However, one may in fact increase the orbit slightly if one used a tactic that would elongate the orbit.

There are essentially 3 options.
A: Move Ceres into an Earth Tangential orbit, followed by a gravity assist to collide with Venus.  This might be the lowest velocity, but would not suffer as much from subtracting the orbital velocity of Venus.  It would be quickest, but also would bring Ceres closest to an Earth collision.
B: Move Ceres into a Venus Tangential orbit.  Ceres would likely be at a higher velocity than in the first case, but would suffer from needing to subtract Venus's orbital velocity from its velocity.  And, there would be less solar assist.
C: Move Ceres into a Mercury crossing orbit.  This would likely lead to the highest energy impact.  While it would be further from the sun, one wouldn't need to subtract Venus's orbital velocity (as much).  This would take more time to set up, but may be worth it if one considered it a one-shot impact.  If one was using a mass wasting plasma engine, then there could be a trade-off with higher velocity vs less mass.

One may, in fact, get close to Jupiter's orbit, and rather than using Earth for the final changes in orbit, one might use Jupiter to direct Ceres sunward, and into Venus.  It should be possible to alter the orbit of Ceres even without crossing Jupiter's orbit.

Breaking apart on impact could be a major problem.  It might depend somewhat on what one did with the atmosphere.  If the atmosphere remains on Venus, then both the atmosphere and the planet would absorb the impact, and less material would reach escape velocity.

If, on the other hand, one had managed to freeze the atmosphere into dry ice, then less energy would be absorbed in the atmosphere, and more would be transferred to the planet, but more material might reach escape velocity, or at least orbital velocity.  Forcing a breakup of the dwarf planet slightly before impact might in fact reduce the propensity for it to knock material back into orbit.

---------------

Governments, as well as monetary systems have come and gone.  However, we have had essentially a constant forward progression in technology and civilization over the last 10,000 years.

The Italians have been building on the Duomo in Milano since 1386 AD, and after nearly 6 centuries of work, they finally finished making the doors in 1965.

I think one could in fact plan a project to take 1000 years, especially if it could be done in stages, and delays or maintenance gaps would not cause a complete reversal of the progress.  Or, perhaps one would establish a self-supporting orbital colony that could continue working towards the final goal of terraforming the planet (if they didn't fight too much over how to do it).  Perhaps one could push the project to 10,000 years, but I agree that any longer term of a project would be beyond our capabilities to have a good chance of follow-through.

#### damocles

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##### Re: How would you induce a spin into a planet?
« Reply #22 on: 04/09/2012 11:06:48 »
Clifford, I am afraid that your very nice orbital diagrams are in error. The sun is at one focus of any elliptical orbit, not at the geometric centre.

#### damocles

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##### Re: How would you induce a spin into a planet?
« Reply #23 on: 04/09/2012 11:19:01 »
In any close encounter between planetary bodies, there is a need to conserve angular momentum. We could make an approximation of a straight line path for Venus and a curved trajectory for a close transit by Ceres, or for a tangential collision with Ceres, and consider linear and angular momentum relative to Venus, or we could consider linear and angular momentum for the Ceres/Venus/Sun system. The latter would be preferable, but harder to calculate. What I cannot quite see is how to calculate the increased angular momentum of Venus in the heliocentric system in terms of a split between acceleration of Venus' rotation, and an increase in the mean radius and eccentricity of Venus' new orbit. Obviously we would want to maximize the former and minimize the latter.

Of course any actual impact between Venus and Ceres would involve a huge dissipation of energy, and the possibility of a significant amount of splash (ejection of planetary material from the collision site) with totally unpredictable consequences.

#### CliffordK

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##### Re: How would you induce a spin into a planet?
« Reply #24 on: 04/09/2012 19:45:40 »
Clifford, I am afraid that your very nice orbital diagrams are in error. The sun is at one focus of any elliptical orbit, not at the geometric centre.
Thank You,

I knew that... somewhere.  Good thing I wasn't a Physics Major

This makes it much more clear why there would be an energy gain by an increase in the eccentricity of the orbit.

So, in the case of the Mercury crossing orbit, one changes the Aphelion of Ceres from 3 AU to somewhere around 5 AU.

Your point of not wanting to make the orbit more eccentric might lead one to choose striking the planet at the Aphelion (.728 AU) even though there might be a slight energy gain at Perihelion.

So, I would simply set the Aphelion of Ceres to 5 AU.  Calculate the velocity at 0.73 AU.  Once the velocity is recovered, square the velocity, and multiply by half the mass for the kinetic energy.  Then compare it to your calculations above.  If only I had a good way to calculate the velocities.  I could probably find the formula somewhere.

The problem with hitting Venus at the tangent of its orbit around the sun is that one would have to subtract Venus's orbital speed of 35.02 km/s.  Hitting it more perpendicular to its motion would not have this problem.  One might, however, be able to conduct a slighshot maneuver to create retrograde motion of Ceres, and thus actually benefit from the difference in planet/dwarf velocities.  However, the slingshot may in fact reduce the speed of Ceres.  Could one do the slighshot at apehelion, around both the Earth & the moon to create a retrograde orbit, and not loose the orbital velocity?

If one struck Venus at aphelion, I don't forsee much (negative) change in orbital eccentricity.

One would have to take care in not initiating an axial wobble.

If Venus was uninhabited, then it would be hard to do much permanent damage to the planet.  But, there is always the bigger concern about not doing harm to Earth.  And, potentially debris from the collision could reach Earth's orbit.  Hopefully only in small pieces.  Of course, one wouldn't want to wait too long for one's dust cloud to settle down, or to clutter up the planetary orbits with debris making it impossible to safely maneuver a spaceship to the planet.

#### The Naked Scientists Forum

##### Re: How would you induce a spin into a planet?
« Reply #24 on: 04/09/2012 19:45:40 »