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# Quickest way to get to The Super Earth, will this work?

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Let me make sure you understand,

Just putting that out there.

I repeat, Gravity slingshots don't work like that. Just orbiting the sun several times will not give you any extra velocity. Secondly the velocity you can gain from an actually gravity slingshot is limited
To just a bit over what you need to escape the Solar system, and most of that will be used up leaving the Solar system.

All you are doing by pursuing this argument is displaying your ignorance on the mechanism of gravity slingshots.

Leaving the canons on Earth is so stupid, the Solar Sail would stop moving after a certain range, if the Baterry Canons were following the sail then it would stay in range to push it, and the Baterry Canons might slow the Craft down, but the Ion Boosters still provide greater thrust than the recoil of Battery Canons.

So now you going to have Ion boosters propelling the Laser cannon, which are going to be much more massive than the ship itself?

if you had Ion egines efficient enough to keep the massive cannon "in range", they would be efficent enough to propel the craft directly. But since Ion engines aren't efficient enough to get the ship up to even a fraction of the speed of light, neither are they going to be efficient enough to keep the more massive cannon "in range" for any significant length of time, especially since they will be fighting against the recoil of the lasers.

Yeah I did, the fact that the battery canons stay in range long enough for the sail to accelerate to a fraction.

No, you haven't. This has nothing to do with the energy it takes to accelerate an object up to a fraction of light speed. That is determined by the formula:

E = mc^2 (1/sqrt{1-{v^2}/{c^2}}-1 )

where v is the velocity you wish to reach. This is the bare minumum you need, no matter how you supply it. All fiddling around with the efficiency does is determine how much more energy you need to provide in order to achieve your goal.

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Gardamorg...   ...fantastic!! I love your imagination. I love your drawings. I love your audacity.   You're gonna be a fine rocket scientist some day -- if these other yahoos don't squash you first

There was a little quiz I took at the end of this year, it said Math, Science and Cosmology were my strongest subjects.   I have to admit school work is pretty easy when I'm working out flaws with you

Now your insulting me????????????????????????????????????????????????   I quit.

Stage One: The craft will use Nuclear Pulse to propel it out of Earth's orbit.

I'm amazed no-one picked up on the issues of Stage 1. A launch from Florida would seem to be unlikely.

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The solar sail would be moving at over half the speed of light, now this trip might not be fast, over 20 years, maybe over 40, but it's still under 100, which is why this is our best alternative, and the quickest way to get there.

Gardamorg...

You're gonna be a fine rocket scientist some day -- if these other yahoos don't squash you first.

I used to dream the same dreams 50 years ago! I drew rocket ships out my ***. I only dreamed of going to Mars. YOU are dreaming of going to the stars. You have the basic concepts: nuclear impulse, ion drive, solar sails (enhanced with solar cannons). I am totally impressed.

The importance of whether or not your idea will WORK -- as you have described it so far -- is not that important. Some rework is obviously necessary to "fine-tune" the trajectories and the techniques. What IS important is that you are beginning to UNDERSTAND the trajectories and techniques. You're developing the vocabulary. You're developing the concepts.

Pretty soon, you'll have mastered the math so you can actually calculate what size nuclear impulse you'll need, and how big that solar sail has to be, and how long will it really take to get to Gliese. And what to <<DO>> when you get to Gliese. Then,...

...then you will be unstoppable.

I love it.

I love it.

Pyro [NASA Rocket Scientist] [no kidding]

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I'm amazed no-one picked up on the issues of Stage 1. A launch from Florida would seem to be unlikely.
Oh, here at hypography we don’t let little environmental issues like launching giant Orion rockets from Earth’s surface bother us! :phones:

The physics failing to add up, however – or, in the case of this thread, no attempt at any arithmetic whatever being made – will almost certainly earn a sound thrashing – as it has in this thread. When it comes to the physics of spaceflight, bluffing and wishful thinking is not allowed! :cup:

Seriously, a spaceflight mission involving sending anything more massive than a Starwisp to another star within a human lifetime will, most believe, require an unprecedentedly huge amount of space engineering, with most of the materials coming from bodies other than earth. The previously mentioned science fictional ship Prometheus requires an fleet of solar powered lasers orbiting closer than Mercury, and a Fresnel lens around the diameter of the moon to focus them. The spacecraft itself – though many times larger than anything launched or assembled in space to the present day - is only a minute fraction of the total system mass.

It’s reasonable to assume that the only thing being lifted from Earth in such an endeavor would be humans, and possibly tools and equipment impractical to manufacture in space. With a fleet of space-built vessels to rendezvous with them, such trips could be accomplished by vehicles little larger or more advanced than SpaceShipOne, with environmental impact a fraction of that of total present day ground and air travel.

Advanced spaceflight and space engineering is not necessarily un-green :)

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I'm amazed no-one picked up on the issues of Stage 1. A launch from Florida would seem to be unlikely.

Why use a nuclear pulse? Use a nuclear light bulb rocket to lift it from the Earth, you might even be able to use a gaseous core nuclear rocket as the booster for the last stage. A throw away gaseous core nuclear rocket. It could be tuned to maximum thrust instead of reuse since you don't want it back.:cup:

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quick question. where's the hell is this 'super earth', this gilese?

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quick question. where's the hell is this 'super earth', this gilese?

Gliese 581 is a red dwarf star some twenty light years distant from our Sun. Gliese 581 c is a large terrestrial planet that orbits within its "habitable zone". It is several times the mass of the Earth. It is the first extra-solar planet found that might meet the requirements for supporting life.

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Gliese 581 is a red dwarf star some twenty light years distant from our Sun. Gliese 581 c is a large terrestrial planet that orbits within its "habitable zone". It is several times the mass of the Earth. It is the first extra-solar planet found that might meet the requirements for supporting life.

I'm betting that Gliese 581 c is more of Neptune or Uranus type planet than an Earth type planet. Of course one of the first SCI-FI novels I ever read (When Worlds Collide) was about a Neptune sized planet that collides with the Earth and it has a Earth sized moon that is left behind in the orbit of the Earth when the big planets eats the Earth and moves on in a hyperbolic orbit from the sun. The idea was a Neptune sized planet could have an Earth sized moon since the Earth has a large moon as well. So if a Neptune sized planet exists around Gliese that planet could have an Earth sized moon..... Ok it's far fetched but at least we know now that a gas giant can exist close to its star.

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Gardamorg...

You're gonna be a fine rocket scientist some day -- if these other yahoos don't squash you first.

I used to dream the same dreams 50 years ago! I drew rocket ships out my ***. I only dreamed of going to Mars. YOU are dreaming of going to the stars. You have the basic concepts: nuclear impulse, ion drive, solar sails (enhanced with solar cannons). I am totally impressed.

The importance of whether or not your idea will WORK -- as you have described it so far -- is not that important. Some rework is obviously necessary to "fine-tune" the trajectories and the techniques. What IS important is that you are beginning to UNDERSTAND the trajectories and techniques. You're developing the vocabulary. You're developing the concepts.

Pretty soon, you'll have mastered the math so you can actually calculate what size nuclear impulse you'll need, and how big that solar sail has to be, and how long will it really take to get to Gliese. And what to <<DO>> when you get to Gliese. Then,...

...then you will be unstoppable.

I love it.

I love it.

Pyro [NASA Rocket Scientist] [no kidding]

There was a little quiz I took at the end of this year, it said Math, Science and Cosmology were my strongest subjects.

I have to admit school work is pretty easy when I'm working out flaws with you guys on this site.

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I'm wondering....what are the chances such a solar sail could travel the expanse between here and Gliese without experiencing any damage? How much damage could such a fragile craft endure without effecting its alleged performance?

Me thinks perhaps your chances would be better at winning the 3 largest lotteries in the world all on the same day...

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The physics failing to add up, however – or, in the case of this thread, no attempt at any arithmetic whatever being made – will almost certainly earn a sound thrashing – as it has in this thread. When it comes to the physics of spaceflight, bluffing and wishful thinking is not allowed!

Jesus Christ Rambo!

What makes me mad, is that, I've had worse ideas, I mean much worse, and you didn't really snap at those, yet when I post this one, you all the sudden get a hard on to bash it!!!!

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What makes me mad, is that, I've had worse ideas, I mean much worse, and you didn't really snap at those, yet when I post this one, you all the sudden get a hard on to bash it!!!!

If you've got that much faith in it then support your claim. Post the math, the physics. Don't get all pissed off because you can't just waltz in here and expect us to believe that it will work just because you say so. If you're looking for a naive audience that will just accept whatever you say then try your local kindergarten. Around here we expect science.

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If you've got that much faith in it then support your claim. Post the math, the physics. Don't get all pissed off because you can't just waltz in here and expect us to believe that it will work just because you say so. If you're looking for a naive audience that will just accept whatever you say then try your local kindergarten. Around here we expect science.

My getting pissed off has nothing to do with whether it will work or not.

I'm mad because your acting like I didn't do it to the best of my knowledge, and that I'm intentionally trying to decieve you and earn respect that isn't deserved.

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I'm mad because your acting like I didn't do it to the best of my knowledge, and that I'm intentionally trying to decieve you and earn respect that isn't deserved.

Oh, I completely believe you've given it your all, your complete ability. The fact of the matter is that you don't have the ability to prove that it will work or the ability to prove anyone's refutations wrong. We're a science forum and when someone comes around proclaiming I've got the best way in the world to get to Gliese we expect them to prove it and do so with real science. Now, can you SUPPORT your claim or not?

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I'm wondering....what are the chances such a solar sail could travel the expanse between here and Gliese without experiencing any damage? How much damage could such a fragile craft endure without effecting its alleged performance?

Me thinks perhaps your chances would be better at winning the 3 largest lotteries in the world all on the same day...

For the sake of argument, let's say we get our light sail up to 0.1c

Using a low-end estimate of 100,000 atoms per cubic meter for the density of the interstellar medium, the total kinetic energy due to collision with said medium works out to about 2.25 joules of energy per sec per meter², or the equivalent of output of a 2.25 watt light bulb shining on every square meter of the sail.

This may not sound like much, but as always, the devil is in the details. In this case, it doesn't matter as much what the total energy absorbed is as it does the form in which it is absorbed. For instance, I could could bask in the 2.25 watt output of a light bulb indefinitely and suffer no harm, but I couldn't say the same for being exposed to the same wattage output in gamma radiation.

In this case, the energy is delivered by hydrogen atoms moving at a speed of 0.1c relative to the sail. this gives each an energy of about 5Mev. Not only is this enough to "boil away" atoms from the surface of the sail, it is close to the range of binding energy for nuclei themselves.

Considering that every square meter of the sail will collide with some 3e12 atoms per second, and the relative thinness of the sail, I wouldn't expect it to last very long at all.

And this isn't even considering the effect of collision with dust and micro-meteoroids.

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For the sake of argument, let's say we get our light sail up to 0.1c

Using a low-end estimate of 100,000 atoms per cubic meter for the density of the interstellar medium, the total kinetic energy due to collision with said medium works out to about 2.25 joules of energy per sec per meter², or the equivalent of output of a 2.25 watt light bulb shining on every square meter of the sail.

This may not sound like much, but as always, the devil is in the details. In this case, it doesn't matter as much what the total energy absorbed is as it does the form in which it is absorbed. For instance, I could could bask in the 2.25 watt output of a light bulb indefinitely and suffer no harm, but I couldn't say the same for being exposed to the same wattage output in gamma radiation.

In this case, the energy is delivered by hydrogen atoms moving at a speed of 0.1c relative to the sail. this gives each an energy of about 5Mev. Not only is this enough to "boil away" atoms from the surface of the sail, it is close to the range of binding energy for nuclei themselves.

Considering that every square meter of the sail will collide with some 3e12 atoms per second, and the relative thinness of the sail, I wouldn't expect it to last very long at all.

And this isn't even considering the effect of collision with dust and micro-meteoroids.

That is why the Star Ship Enterprise has navigational shields, with out them it couldn't travel even close to the speed of light much less hyperlight. I recall more than a few times when this happened and they had to slow down big time! (don't you just love Science Fiction when it's done right!) I remember reading another sci-fi story about a star ship powered by zero point energy, it was driven to very close to the speed of light but it had to have a shield of ice sever kilometers thick to avoid being destroyed by interstellar dust. They talked about boring a hole through space with the ice shield. (Songs of Distant Earth, A.C. Clark)

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I recall reading a book by Issac Asimov on the topic of star travel, and IIRC his idea was a hollowed out asteriod, and thousands of years travel time even to the closest stars. Given our current technology, IMHO, no one has come up with with a better idea yet.

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