Nuclear rockets are very very very bad idea?

[Wenderro]

What is the difference of nuclear-thermal or nuclear-electric rocket.

And what happen to project Orion or project Daedalus they where nuclear and could take of from earth.

Nuclear-thermal Rocket - the reactor heats up the fuel directly, like pumping hydrogen thru the reactor
Example: NERVA
Tech Level: prototypes build, ready to fly
Applications: 2nd stage rocket, in space propulsion
Safety: I was unable to find how much radiation it releases or how bad an exploded engine in Earth atmosphere would be

Nuclear-electric Rocket - A reactor is used to produce electricity, just like nuclear power station here on Earth and with that electricity u power an engine
Example: engines:Ion engines, VASIMR reactor: Project Prometheus
Tech Level: engines: already used(ion) reactor: tech basically ready, just a small research needed to adapt to space conditions( If I remember correctly some were actually used in space)
Applications: only space propulsion but a very efficient one
Safety: until a nuclear reactor is powered up the radioactive emissions are negligible and since u start the reactor after u reached space makes it the most safe of them all assuming u don't use it on a satellite that will eventually re-enter atmo

Nuclear pulse propulsion - you use nuclear bombs detonated behind to push your ship
Example: Project Orion and Daedalus
Tech Level: Research has been done, some research still needed
Applications: anything , but it does require a huge ship(because if the ship is too small a bomb will destroy it or accelerate it too much)
Safety: probably by far the most unsafe to use it as a launcher since u blow up many nuclear bombs and no matter now clean u make them they will still poison the launch site extremely, however in deep space that is not a problem


Other notable nuclear-propulsion:

Nuclear powered ramjet - Project Pluto - 2 experimental engines build, project scraped in 1964! because the missile fitted with this tech would be considered "too provocative".


IMO u need one of these types of propulsion to be able to sustain a long term manned exploration, else u just redo the Apollo again(make a mission to Mars and the the whole program is scraped because is too expensive).

My proposal for launch to EO:

A carrier aircraft using a combination of chemical rockets and Nuclear powered ramjet
The launcher itself using Nuclear-thermal Rocket.

This type will give us the heavy lift capability and also a much lower cost all using ALREADY KNOWN TECH

 

[orionrider]

So basicaly your saying there is no point to a space program besides launching satelites.....

I was referring to the use of nuclear or antimatter detonation to propel a spacecraft.
It could enable very ambitious projects, like interstellar probes and massive interplanetary ships, but not in the near future.

Before we get to that point, conventional nuclear propulsion (like NERVA) will be required because chemical rockets are not good enough to do more than orbit satellites and send small vessels on modest missions.

It is very unfortunate that many people associate things 'nuclear' or 'atomic' to the effects of nuclear or atomic weapons. There is more difference between an A-bomb and a nuclear reactor than between the Space Shuttle and a ballistic missile. Yet the public loves the shuttle. Go figure... :?

 

[nec208]

Nuclear-thermal Rocket - the reactor heats up the fuel directly, like pumping hydrogen thru the reactor
Example: NERVA
Tech Level: prototypes build, ready to fly
Applications: 2nd stage rocket, in space propulsion
Safety: I was unable to find how much radiation it releases or how bad an exploded engine in Earth atmosphere would be

Why is Nuclear-thermal Rocket cannot lift off from earth to take stuff up into space.I will like more information about Project Orion and Daedalus and how it can take up more payload .How many times more payload and how fuel efficient is it.

 

[Wenderro]

Why is Nuclear-thermal Rocket cannot lift off from earth to take stuff up into space.I will like more information about Project Orion and Daedalus and how it can take up more payload .How many times more payload and how fuel efficient is it.

A Nuclear-thermal Rocket doesn't provide enough thrust to be used as 1st stage on a rocket.

If u want more information just go wikipedia.

 

[Jim_LAX]

In addition to the Wikipedia article referenced above, James Dewar has written a book called "To The End of The Solar System: The Story of the Nuclear Rocket". It has a lot of detail about the research and developmet done on project Rover/NERVA over a 20 year period, as well as the politics that eventually killed it. Instead of NERVA, the state-of-the-art nuclear system developed by the Rover program, Congress was sold on the Space Shuttle, outdated before it was launched. Instead of the solar system, we got low-earth orbit.

 

[EarthlingX]

You may also want to check this thread :

Russian space travel

 

[Boris_Badenov]

Why is Nuclear-thermal Rocket cannot lift off from earth to take stuff up into space..

Nuclear lightbulb
Gas core reactor rocket
A Gas Core Nuclear Rocket Engine can get up to .5 Mass Fraction. :shock: That's in the neighborhood of your average commercial passenger jet.

 

[tnjen]

I admit I was geeked by having 4 brothers being Star Trek fans, so being the only girl in the house aside from my mom, I became a Star Trek fan myself. That said, I have had the chance to watch a lot of real space history over the years, having been born in 1959. It excites me in seeing mankind on the cusp of such breath taking advancements in space travel. The Vasimr engine in conjunction to the sealed nuke reactors/ nuke batteries producing the 200 Mw that is needed to fully power the Vasimr engine makes it now possible to make most, if not all of the solar system within reasonable reach of manned flights. So many discoveries within just the small little confines of our own solar system; potential caves on mars
( colonies), water all over the place, potential discoveries of life (albeit microbial life), and of course minerals galore. This is just a mere skim of the top of potentials of an efficient interplanetary rocket system. The discoveries (by human not robotic hands) in our solar system will most likely keep us amazed for decades to come, if not longer. The "Moon, Mars,and Beyond" concept is nice start, but where we could be if we chose, is the solar system and beyond.

 

[Wndflr]

Remember the concept of the Orion space ship? Pulsed small nuclear explosions pushing the spaceship in space for propulsion. If we had develped it we would already haved manned exploration of the entire solar system since the 70's. It was extensively researched and deemed extremely doable. Fears of the nuclear killed it. Defense still researches the concept. Look it up.

 

[Paul_L_Smith]

Types of "nuclear" propulsion and their ISP's (efficiency) and High vs Low Thrust

Best Chemical Rocket (Shuttle SSME)           ISP=450 (Vac)          High
Nuclear-Thermal Rocket  (NERVA)               ISP=800-900            High
Gas-Core Nuclear-Thermal Rocker (light bulb)  ISP>2000               High
Nuclear Pulse Rocket (Orion)                  ISP>20,000           Very High
Nuclear Electric (ion / VASIMIR)              ISP=2,000-100,000      Low
Antimatter Pulse Rocket (?)                   ISP>1,000,000         Varies

Lots of options and other than the first two, none are proven technology.

My personal vote would be for Nuclear-Electric + VASIMIR and the Nuclear part being a Bussard Polywell Fusion Reactor.
(See links at the http://www.emc2fusion.org web site for more info)

 

[garyegray]

Definitely a bad idea for ground launch vehicles, however, I have often thought that small nuclear rocket engines might make sense for ships in space. Re: http://en.wikipedia.org/wiki/Nuclear_thermal_rocket

These rockets do not weigh a lot and the amount of nuclear fuel required is minimal for these types of engines, especially the solid core design. For a ship in orbit, you do not need a lot of thrust, just a high Isp - or specific impulse. Fortunately, these designs do offer a fair amount of thrust and an Isp that is high compared to conventional rockets.

Keep the nuclear component to a minimum to minimize risk, and I think nuclear makes sense.

 

[Ruri]

No nuclear rockets would be a very very very good idea.
They are used in space and not on earth so the exhaust would pose no danger.
If there is an accident launching a nuclear rocket the fuel is in ceramic form and would not cause a massive ecological disaster like Chernobyl.

Yes the fuel pellets would be hot but they won't leach into the environment.
Clean up would be a relatively simple operation and would be easier then cleaning up after an offshore oil platform or oil tanker mishap.

Use of BNTR over chemical plus solar can mean the difference between 5 or 7 months getting to Mars and having radiation shielding or not.
It also means having hundreds of kilowatts of electrical power vs tens of kilowatts.
In space electrical power is life.

 

[StanislawUlam]

Thank you SpaceJeff for finally mentioning NERVA and saying something reasonable about how these solid core nuclear thermal engines that were developed by Westinghouse and Aerojet between 1959 and 1973 were capable of doing precisely what so many other posters here said cannot be done. (Deliver 75,000 pounds of thrust and 850 seconds of specific impulse.) As you are probably aware, James Dewar has detailed much of this information in his two books, "To The End of the Solar System," and "The Nuclear Rocket." Further, additional information is available in "From Underseas to Outer Space" by John W. Simpson, a former president of Westinghouse Electric Company who originally directed the Westinghouse Astronuclear Laboratory outside Pittsburgh, Pennsylvania.

 

[Kansan52]

Good points.

Yes, the right nuclear engine combination cuts months to years off long missions making them (supplies wise) much more doable.

But it won't happen. It needs money and until the space community can rise with one voice and shout out "More" then all we will have are studies.

Instead of a fraction of 1 percent of the Federal budget, spend the money to build the nuclear-thermal or nuclear-electric ship to Mars. This means a new heavy lift launcher to put the pieces up. Maybe build it at ISS or a Bigelow orbital facility. SuperCots can ferry the people to do the job.

Ideally, a moon base could supply ice to the Mars ship as a water supply and radiation shield (mostly from solar flares) but we would probably haul the water up the gravity well here. There would be great need of robotics as a pathfinder, need of ISS or a moon base to test systems for the trip. A robotic version could do great trips to the outer planets or herd asteroids to Earth for materials or away from Earth for safety.

Oh well, it's easy to plan but seems no way to fund it.

More Bucks, More Buck Rogers. Just say More!

 

[Valcan]

So basicaly your saying there is no point to a space program besides launching satelites.....

I was referring to the use of nuclear or antimatter detonation to propel a spacecraft.
It could enable very ambitious projects, like interstellar probes and massive interplanetary ships, but not in the near future.

Before we get to that point, conventional nuclear propulsion (like NERVA) will be required because chemical rockets are not good enough to do more than orbit satellites and send small vessels on modest missions.

It is very unfortunate that many people associate things 'nuclear' or 'atomic' to the effects of nuclear or atomic weapons. There is more difference between an A-bomb and a nuclear reactor than between the Space Shuttle and a ballistic missile. Yet the public loves the shuttle. Go figure... :?

It was a dam shame they canceled NERVA it was a great program and very needed. Chemical rockets are plenty powerful its just getting the fuel there. I think i head if we used a rocket the size of the Saturn 5 we could have a mission to mar in about a week.

 

[a_lost_packet_]

Project Orion (nuclear propulsion)
From Wikipedia, the free encyclopediaJump to: navigation, search
For other uses, see Project Orion (disambiguation)....

Two things -

First, one must limit themselves to "Fair Use" when copying and posting third-party materials. Copying an entire article is not "Fair Use."

Second - A link to the specific article, if online, is necessary. While this is obviously a wiki entry, one still needs to provide the link. A copy/pasted URL address is satisfactory.

As far as Orion goes, it's one of my favorite subjects. Nuclear Pulse Propulsion is very efficient but, there are some downsides. Obviously, launching something the size of a city block or an aircraft carrier into space riding on the wave of a nuclear explosion, while tremendously cool, has its environmental concerns. Namely, one may not be so enthusiastic about NPP launches if one realizes that a hundred people could die, across the world, from the immediate effects of radiation for each pulse. (Estimate of number of deaths per nuclear test due to atmospheric contamination.)

Another problem is that while it appears that NPP could work, actually building enough pulse units would be problematic. A mission to Mars would take more material than is contained in both US/Russian stockpiles, even using Cold War estimates, IIRC. That might be made easier today, if we put our minds to it. But, the fact is that we would still use a very large amount of fissile materials/bombs in order to get anywhere significant within any efficient amount of time.

(However, if there was ever a need for us to put something really, really big into space in short order, a resurrected Project Orion could do it...)

A great book I highly recommend is "Project Orion: A True Story of the Atomic Spaceship" by George Dyson, Freeman Dyson's son. An excellent and highly entertaining read!

 

[orionrider]

"Antimatter catalyzed nuclear pulse propulsion" could be an answer. The critical mass of Pu239 could get down to a few grams, which means the detonation can happen much closer to the spaceship, with gentler effects, enabling the use of a lighter, deeply parabolic shield, to direct the effects.

Only, we cannot (yet) contain antimatter

See here: http://www.statemaster.com/encyclopedia ... propulsion

 

[Valcan]

"Antimatter catalyzed nuclear pulse propulsion" could be an answer. The critical mass of Pu239 could get down to a few grams, which means the detonation can happen much closer to the spaceship, with gentler effects, enabling the use of a lighter, deeply parabolic shield, to direct the effects.

Only, we cannot (yet) contain antimatter

See here: http://www.statemaster.com/encyclopedia ... propulsion

I was under the impression we have a very small amount contained atm it just takes a rather large facility..

 

[Wenderro]

Not only the containment is a big issue but also producing it($62.5 trillion per gram of antihydrogen based on NASA in 1999).

 

[Valcan]

Not only the containment is a big issue but also producing it($62.5 trillion per gram of antihydrogen based on NASA in 1999).

LOL yea which is why we've only been able to make a few atoms of it.

Well, that and what would happen if it got lose. Would it be easier to produce in space?

 

[nec208]

Some thing clearly needs to be done .Only 3 countries can put people into space and 2 of the countries are questionable.Only 3 countries and for how long is anyone guess with pressure to cut back!!

It clear that chemical rockets need to be built better or move to laser propution ,anti-matter or nuclear if one wants open up the gates for space to every country or at least 5 or 8 rich countries than the way it is now .

 

[EarthlingX]

Some thing clearly needs to be done .Only 3 countries can put people into space and 2 of the countries are questionable.

:lol:
Of course, for any of them

 

[orionrider]

Only 3 countries can put people into space

I think many more can put people into space. The Japanese could do it, Europe definitely, Israel and India probably,...
They don't do it because of costs, risks and the fact that it is not necessary. Manned spaceflight is more of a political statement than anything else. It will take many years before it becomes profitable.

 

[nec208]

Only 3 countries can put people into space

I think many more can put people into space. The Japanese could do it, Europe definitely, Israel and India probably,...
They don't do it because of costs, risks and the fact that it is not necessary. Manned spaceflight is more of a political statement than anything else. It will take many years before it becomes profitable.

In order for those countries you say above or more countries some thing needs to be done to make chemical rockets better or move to laser propution ,anti-matter or nuclear. If that does not work no one will be going any where in space.And mostly likely manned spaceflight will be of the past.

 

[MeteorWayne]

What is the differnce of nuclear-thermal or nuclear-electric rocket.

And what happen to project orion or project daedalus they where nuclear and could take of from earth.

If you don't know the answer, what was the point of starting a discussion on something that you don't understand?