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# 1G Relativistic Rocket Ride, Wheeee

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If anything it would be slowing the moon down since meteorites would strike more frequently on the side of the direction of motion rather than catching up to strike on the other side. Meteorites are mostly tiny and far outweighed by other effects, sort of like trying to knock the ball off of a large stone kugel by throwing stones at it (you probably couldn't even lift a stone large enough to noticably affect it).

I'm not sure if you understood the idea . maybe you didn't read the whole story

take this example and explain it for me more . I want move the moon so I decide to built a machine ( the rocket moon ) the head of the rocket it's moon it self and the back of the rocket will be the machine look at this picture . if I start the machine do you think the moon start to move or not ?

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Gamma tends to infinity as you approach c. It's not Gaussian.

It isn't a bell curve?

http://en.wikipedia.org/wiki/Lorentz_factor#Values

You would maintain your speed if you shut the engines down, and if you restarted them you would begin to accelerate again.

So, would the acceleration of a constant Force rocket slow its acceleration as speed increased? And restarting the engines would be less then 1G?

Merged post follows:

Consecutive posts merged
... if I start the machine do you think the moon start to move or not ?

mass of the Moon * (the speed of light^2) = 6.61483812 × 10^39 joules. You will need a big rocket and please do not point it towards Earth.

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"force would be force" it's true but there is a less and a more force

at 1st newtons law ". Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it."

as based of your theories and 1st newton's law you can move 1000,000 tons on space with one finger if and only if that is true then your theories will be true .

but I can't see that happening . our space most of it is empty and there is a moon and it's on an empty space without any resistant , that moon has no atmosphere so if it's hitting by Meteorite ( as it's a moving object it means it has a force or at least what Newton thinks) it should force the moon to accelerate !!! why would that not happening .

still all the three Newton's laws confusing us

I don't know what does Issac Newton mean by "external force is applied to it" ?

Yes, every meteorite that hits the moon accelerates by a tiny, tiny, tiny amount. Any force at all can move it. When you jump up in the air here on Earth, you're also pushing the entire rest of the Earth downwards by a tiny, tiny, tiny amount. And when gravity pulls you back towards it, you're also pulling it towards you with the same force. But since the Earth is so much bigger than you, the effect is too small to notice.

And yes, that rocket sticking out of the moon would move it. But the moon is so large that it would take probably a billion years of thrust to make any noticeable change.

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It isn't a bell curve?

http://en.wikipedia.org/wiki/Lorentz_factor#Values

So, would the acceleration of a constant Force rocket slow its acceleration as speed increased? And restarting the engines would be less then 1G?

Merged post follows:

Consecutive posts merged

mass of the Moon * (the speed of light^2) = 6.61483812 × 10^39 joules. You will need a big rocket and please do not point it towards Earth.

who said I want reach the moon to speed of light ?

I just want to accelerate it > 0 in noticeable way .

Yes, every meteorite that hits the moon accelerates by a tiny, tiny, tiny amount. Any force at all can move it. When you jump up in the air here on Earth, you're also pushing the entire rest of the Earth downwards by a tiny, tiny, tiny amount. And when gravity pulls you back towards it, you're also pulling it towards you with the same force. But since the Earth is so much bigger than you, the effect is too small to notice.

And yes, that rocket sticking out of the moon would move it. But the moon is so large that it would take probably a billion years of thrust to make any noticeable change.

I'm still laughing but really that was the best answer. I guess we have to wait another a billion years to discover the moon escaped from the gravity of the earth.

========

can someone tell me if this motion will goes in a liner or a curved way .

as I now the velocity increase with the time in liner way .

how can I calculate the acceleration in every moment , with variable (v) and (t) ? as I know ?

a = dv / dt

or

vf = vo + at (f = final , o = original )

or something else .

I mentioned before but I didn't notice that things . as we know thrust comes from the blast and that comes from fuel . and of course fuel has a mass that mass connected with the spaceship .so with same thrust and a variable mass of fuel on that ship will make the spaceship continue at 1g until the fuel will be zero .

in that way it will be more logical .

I have to take my ticket in that journey .

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who said I want reach the moon to speed of light ?

I just want to accelerate it > 0 in noticeable way .

You mixed my merged reply to swansont and you together. I understand what you are saying.

Merged post follows:

Consecutive posts merged

I stand corrected. I was considering the first 40% of the bell curve and not the complete curve. Making up my own definitions is not good.

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I'm not sure if you understood the idea . maybe you didn't read the whole story

take this example and explain it for me more . I want move the moon so I decide to built a machine ( the rocket moon ) the head of the rocket it's moon it self and the back of the rocket will be the machine look at this picture . if I start the machine do you think the moon start to move or not ?

As stated by several people, the moon will definitely move. Whether you could, in practice, apply enough force to make it noticeable is a different question........

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... as we know thrust comes from the blast and that comes from fuel . and of course fuel has a mass that mass connected with the spaceship .so with same thrust and a variable mass of fuel on that ship will make the spaceship continue at 1g until the fuel will be zero .

in that way it will be more logical .

I have to take my ticket in that journey .

I do not think changing mass from fuel consumption is considered in the numbers in my first post. You will notice it takes 2 years to reach .97c and then another 10 years to reach .99999..c . It seems that maybe the rocket accelerates slower and slower as the speed increases because of this so called relativistic mass.

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I do not think changing mass from fuel consumption is considered in the numbers in my first post.

The numbers you quoted from Baez' Relativistic Rocket article simply assume the spacecraft has a constant proper acceleration of 1g. If you read the article further you will see how much fuel is needed to accomplish this voyage, and that is assuming perfect conversion of mass to photons.

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The numbers you quoted from Baez' Relativistic Rocket article simply assume the spacecraft has a constant proper acceleration of 1g.

Exactly

If you read the article further you will see how much fuel is needed to accomplish this voyage, and that is assuming perfect conversion of mass to photons.

A starlight solar sail would be nice but it doesn't look like we should hold our breath waiting for that to be developed. We have a long time to go before this trip is made for several reasons.

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I do not think changing mass from fuel consumption is considered in the numbers in my first post. You will notice it takes 2 years to reach .97c and then another 10 years to reach .99999..c . It seems that maybe the rocket accelerates slower and slower as the speed increases because of this so called relativistic mass.

if I count the vectors of the rocket I will say , it will accelerate in curve way that means - at least for me - the acceleration will divide it in x ,y and z maybe it will go like twister way . or maybe those rules doesn't count in this situation .

I did read some wikis things about acceleration it's seem the equations can't used in 1G relativistic state .

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