That would be too easy.

Let's step-by-step it:

Our reaction produces 18.4 MeV. That's a tremendous lot. We whip out our Conversion Factors and find that that is equivalent to 21340000000 Kelvin. Ouch.

Now we put these temperatures into the Kinetic Temperature Equations for our products (80% He-4 and 20% H) and find that our most probable speeds are 29787994 for He-4 and 59575988 for the H - an average mass speed of 35745592 m/s.

Now, this is all plasma, so it's magnetically active, we can bounce it off of magnets. It's already super-fast so we don't need a magnetic accelerator, just a magnetic bottle with a hole in it for the plasma jet to shoot out of. Assuming that it shoots out the back at its current speed, we are now caught up in the wild world of Conservatin of Momentum. See, if part of the original mass is going out the back at an average of 35745592 m/s, then remaining vehicle will have to go forward at a speed proportional to its mass so that the momentums (velocity times mass) sum to zero.

Or to put it another way, we now have the magic equation:

9.8 m/s * (100,000 kg - N) + -35745592 m/s * (N) = 0

Where N is the mass of the ejecta out the back. I assume we can all do basic algebra, and we are left with an N being .002798 kilograms. For the first second

Now as the vehicle continues to hurl mass out the back, it will have to throttle down some or the acceleration will increase. Our ratio stays constant each second. .000027 % of the total mass every second, for 187200 seconds round about.

So we now have a compound interest problem, where we have .9999997258^187200 and we have 94.9978% of our original mass at the end. Since our original mass was 100 tonnes, will still have about 95 tonnes left, so we've shot out about 5 tonne of ejecta out the back.

OK, now that we've done all the math with the actual inputs instead of just made up stuff, can we call it a day? Or rather, 2 days?

Edit: Sorry, I plugged in for 1 m/s. We're looking for 9.8 m/s. 1 m/s thrust needs only 522 kilograms of reaction mass for the trip. It's 5 tonnes for the full 9.8 m/s.

-Frank

You’re confusing temperature with energy. This is a common problem you are having, thinking one thing is as good as another and calling it done. Frank you keep making absurd claims like Energy is as good as speed, energy is as good as temperature. In fact you may see Temperature expressed in terms of energy, but then they are using it as an average Kinetic Energy. What you’re claiming as a energy is the energy released by a reaction.

In fact if you look at your Artemis project site that 4He gets 3.7MeV not 18.4, that energy is shared between the proton and the 4He.

Then you also seem to think that we can just collide these two things and get the directionality we want and no further interactions, when in fact much of that energy will go into interactions with the remainder of the plasma heating it and allowing it to further fuse and allowing your reaction to keep going. In the end you’re getting an averaging effect within the plasma.

As you add feedstock to maintain the reaction, and you have to add it at the same rate you eject it for propellant, you’re cooling the reaction by introducing a cooler gas.

So Frank, you see 18.4 MeV and you find a conversion factor to temperature and you wildly misinterpret both!

You interpret that 18.4 MeV as going exclusively into the 4He.

Then you take your already wrong 18.4 MeV and wildly misinterpret it as an average kinetic energy. Where in fact that has only to do with the energy out of the reaction that will have to undergo an immense series of interactions within the plasma, distributing that energy and averaging it out with all the other particles in the plasma.

So basically all that work you did in your above two posts are based on a flawed premise processed through a flawed set of assumptions and it outputs worthless information.

Or rather:

I do really want to believe you’re just trolling here, and just trying to get a rise out of me and others and that you don’t actually believe this. But the frightening thing is I don’t think that is the case.

Take this advice, your local community college or university will have physics professors, they will have office hours where you can go in and ask a question, and most would have no problem with you doing this even if you’re not a student, so long as you don’t happen to come to them the week before they are giving an exam and have a flood of students trying to cram for the last minute.

For me to point out all of these flaws over a forum such as this I basically have to write a textbook because the level of interactivity is not nearly what you would find in a one on one setting.

But be careful you may actually learn something, that is if you’re more willing to listen.

edge is *partially* luck. it is other things as well.

you're not just luckier than a gang of random thugs, you've got experience under your belt, etc etc... and therefore you have a higher edge.

Actually, it's January 4th 2072 in our game, (timelines move forward when you're playing a game a week) which according to a Mars/Earth orbit site I looked at would put it well within 100 million Kilometers.

Unfortunately, I've seen variations in different mars sites. I have no idea why this would be the case because these orbits have been studied for thousands of years and don't really change.

-Frank

Amazingly enough, in Franks defense, he proposed an equal time accellerating as decelerating. Ideally you'd be coming into a stable orbit fairly simply...

Wait... does that mean Damian Knight will only wipe his ass once? Ever?

True. But as the "two days" thing is still going around I'm gonna suggest an extended period of acceleration. And it's not like aerobraking hasn't been field tested. That's what the Mars Reconiasance Orbiter was for. Well, that and observing.

Also, it's not like they won't see us coming anyway. They have to have an observatory up to watch for things coming by.

Your tone has been really condescending from the very beginning of this thread. Maybe if you threw in fewer insults you might find yourself a little less frustrated.

And myself? I like to think that I've been consistently polite ever since I joined these boards, and I've been repeatedly disregarded where I've pointed out errors in Frank's understanding. And Demerzel's comment is hardly a wild insult, but rather acurate - numerous criticisms have been ignored. Happily physics doesn't follow the laws of etiquette.

To make the science easier, try a lander. The ship never has to land, never has to waste energy taking off again. And the lander could be run on whatever chemical propellant you want, even the abysmally inefficient magnesium reaction used by the space shuttle.

Ah, but acceleration is a function of the rate at which the fuel is burned. By burning the same amount of fuel in 1/365th the time, such a craft could achieve remarkable acceleration. All you need is an engine that can accommodate that rate of burn, which is what I'm trying to point out. It is a matter of scale, rather than a matter of absolute limitations. 9.8m/s^2 acceleration is a fuckton more expensive than 0.34m/s^2 acceleration but it is most certainly possible. It is possible with plain ole' chemical rockets if you have the fuel to waste.