Why are we still using rockets?

Oh we have clearly developed energy sources that far far outpower oil. Its not a secret either, its nuclear energy.

Events like Three Mile Island, Chernobyl and matters like waste disposal etc... has giving rise to a fear that has hindered nuclear energy from reaching its potential.

i dont think i like the idea of a million nukes drivin around my city

it sounds like a lot of risk regardless of potential, relying on the average joe like myself to regularly maintain his nuclear car is asking alot.

You wouldnt use nuclear reactors or batteries in the cars.

You would use either electrical cars with the energy produced at nuclear plants. Very very safe for cars.

Or you would use hydrogen in cars but nuclear energy would be used to convert water into hydrogen. Really thats just as safe in cars as explosive gas.

Hmm interesting subject. One of the problems I wish to tackle in the future of Aerospace Engineering.

Just depends on the imagination to think it up and the physics to back that up.

An idea I had was just something to force itself against Earth's gravitation field, sort of like.. well anti-gravity! I believe if the Earth's magnetic field was strong enough we could use magnetic propulsion.

Take a look at the picture I've drawn.




This image shows a long tube, in which the bottom Blue magnetic plate is forced upwards towards the Red magnetic plate causing a force that would send the ship sailing into the atmosphere.



Edit: The Red Plate is attached to the ship, now if we can harness enough magnetic force to even do that, I'd like to see, just an idea, pick it apart if you choose.. haha.

[edit on 6/3/2006 by Masisoar]

While I won't rule out some magnetic concept in the future, I think rockets are the best we've got at this point.

I'm not sure how the whole scram-jet idea is going, but a staged approach to launching payloads in leo could be the go.

In years to come perhaps flying something the size of 737 to a certain height, then perhaps the cargo in a seperate module with some 'meaty' scram-jets bolted on could finish the transfer into LEO. Compressed 02 could feed it as the air gets thinner...??!?!?!?

Though I'm sure this idea has been explored, and my lack of understanding doesn't add any cred to it.

The sooner a global approach to space exploration is taken, the sooner we'll see advances in this area. NASA, JAXA, ESA etc if their budgets were combined, I'm almost sure something good would come from it... ??

OSS

We should just use giant sling shots !!!

i think we have enough resources to use a maglev aircraft to get out of earth.
if we get some computers to control a magnetic flow that works against the earth's, and a nuclear reactor to power it it should be possible right?

as I posted in another thread, I don't think it is wise to put a bunch of uranium/plutonium and other fission products up into space. A re-entry accident would send all of the nuclear material into the atmosphere....so the old saying goes 'don't sh*t in your own backyard..'.

Now, the real question should be...why do we still use cars!?? It has been a hundred years and we still rely on the combustion engine for transportation, etc.., it is pathetic. There are so many patents and ideas out there that are silenced so that outdated technology remains and the companies that rely on them swell with cash....

I can't wait until we get our jetsons cars...

And as people probably replied (or at least should have) in the other thread, you're really misinformed. We regularly, and by that I mean every couple of years, launch probes that rely on RTGs, which, while not nuclear reactors, still have radioactive material on board.

Do they pose a threat if they were to fail on launch and the rocket explode or need to be detonated? Do they pose a threat if they were to fail to attain orbit and reenter the atmosphere? Not in the slightest. So why should nuclear reactors be any different?

These probes only have a small amount of nuclear material in them, which provide a small amount of heat to power the probe. You can't really compare a probe with a large space ship powered by a 'reactor' of sorts, now can you?. So no, im not misinformed, however, you may be. Thanks.

[edit on 113030p://555521 by porky1981]

So a containment vessel still isn't a containment vessel? Go figure...

As you can see, I wasn't comparing an RTG to a reactor. Just the fact that the containment for them really wouldn't need to be all that different - just larger, if anything.

[edit on 6/22/2006 by cmdrkeenkid]

can't compare apples and oranges

No, but don't give yourself a false sense of security.

--

Rockets are convenient because they are effective, reliable and cheap compared to any idea that has been offered in contention.

The motivation for a propulsion system other than the rocket (to reach space) is deliquent. Motivation being key because there are only a few nations, the US and maybe Russia and the conglomerate EU, who are at all capable of researching and developing new propulsion systems. Beside that, rockets are used primarily to place spy satellites, weather instruments, etc into somekind of earth orbit. When it comes down to it, few of these satellites have an apogee no further than 24k miles away from earth at any given point. The rocket works just fine.

Heard the rumours about NASA civil servants?

And if you think rockets are old, we still use the wheel after all these years!

[edit on 22-6-2006 by enaught]

Well, he who is so wise in the ways of wisdom... Care to explain on how the containment vessel for an RTG would differ from the containment vessel for a reactor? As I have already said, I don't believe much would need to be different aside from the size.



JAXA is doing a lot in the way of research on ion propulsion. Just thought I would add that into the list.



Exactly. So you could use a normal chemical rocket to loft an interplanetary/stellar probe that utilizes nuclear or some other exoctic form of propulsion to that orbit. Then engage the other form of propulsion in space and you're off!

okay, a containment vessel. Well, lets put this into perspective. Pu238 powers these RTG space probes you are referring to. Pu238 emits mainly alpha radiation, which generates ~2-3 watts of electricity to power the probe. Alpha radiation requires minimal shielding.... however, they still use multilayered shielding as a form of containment.

Now lets take something orders of magnitude larger in terms of nuclear fuel, lets include extremely high neutron fluxes, extremely high gamma radiation from the core, this coupled with the fact that the energy deposition on the containment vessel (i.e., protective shielding, containment, etc..) will be significant, not to mention the huge pressures the containment must withstand....and you have a completely different beast.... you can't compare apples and oranges.

Good points but in order to make space travel routine it is necessary to have a new way of traveling through space that doesn't cost more than what we are spending today. the first obstacle is to have spacecraft that take off from a horizontal possition, then you need that same space craft to be able to achieve re-entry without the dangers the shuttle faces everytime it does that, and the last but most important it all has to be in one piece of equipment not a multi stage like today. in order to keep things small you need a better power plant a generator of some kind of energy that will propel the spacecarft in both earth and space using the same energy source. do you see were i'm going?
I realize that this is easier to say than to achieve but NASA should have been developing something all this years besides jets and rockets.
And yeah i do agree with you that we should have flying cars by now.

Where's the need? Innovation and invention comes when the need exists. Presently we have no need for anything better than a big tube full of explosives with a few daredevils and floating cameras strapped to the nose.

Space planes, high speed interplanetary propulsion systems, whatever... where would they be used? Without a need to fill there's no way such a project would get funded. When we have some place profitable to go there will be a need. But until then it's a bad investment strategy.

>
bah... I hate it when that happens. Uhm that ^^ was in response to the last post on the previous page. Humbug.

[edit on 8-7-2006 by apc]

The first airplanes were made by private individuals making their own research. The making of an airplane was a task that was within the reach of the technology and funds those individuals could get.

The same thing happened with the rockets, the first experiments were made by some people trying something new, but the difference is that a rocket, to be able to transport anything useful, is too expensive to be built by some guy doing research.

Also, airplanes had a good reason to evolve, called World War I. At the time rockets were useless as a weapon, so they did not evolve.

In World War II they were used as a weapon, and todays rockets are just a step over those rockets. Even WWII rockets were too expensive, and they were only built because they could be used in the war.

Also, the Earth's gravity is too strong to use some of the other known propulsion methods.

Also, some of the methods that could be used are really useless because of the acceleration they provoke is too high, like in the Jules Verne story where they are shot from a canon.

Do we need to launch into space at high speed? how about using hydrogen as a light gas to reach the atmosphere, then burning the hydrogen in a controlled way to reach orbit. Im no astronaut but it sounds good to me! how much hydrogen would you need by the way? I know its dangerous but so is rocket fuel. Even if it took a day to reach orbit wouldnt the cost cutting make it worthwhile?

Or am i talking BS...