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Nuclear Pulse Propulsion – Orion and Beyond (2000) [pdf]

ntrs.nasa.gov

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Re: Nuclear Pulse Propulsion – Orion and Beyond (2000) [pdf]

#91

Post by grkvlt »

elsonrodriguez wrote: post #78
grkvlt wrote: post #52

Earlier quoted context omitted.

Even then, we can still send rovers more cost effectively than people! You can throw away the life support mechanisms, and so on, and get 550 tons of pure mars rover in your interplanetary transport. At ~800kg for a curiosity-level rover that gives about 600 rovers, instead of 100 people. What to do with your 600 curiosity rovers on Mars is left as an exercise...

The Curiosity rover has driven 9 miles in a little over four years on Mars. The Lunar Rover that came with Apollo 17 drove 22 miles in a little over 4 HOURS. As it turns out, humans are the best robots.

Yes, but with my super-rover-transporter system, we can cover 5,400 miles in the same time, with the 600 rovers. I'm envisaging a sort of airbag deployment system (like pathfinder) coupled with a dispenser system that fires a rover out every few minutes as the ship orbits the planet, for optimal coverage.

Re: Nuclear Pulse Propulsion – Orion and Beyond (2000) [pdf]

#92

Post by diamondlovesyou »

binarytransform wrote: post #79
maverick_iceman wrote: post #68

Earlier quoted context omitted.

Anything that can accelerate a starship to a velocity of ~0.1c can have devastating consequences if pointed to earth. Just like planes can be used to destroy skyscrapers. Chicken littles notwithstanding, having a much faster mode of transport is worth the risk.

It may be worth the risk but that doesn't change the fact that what you refer to as "Chicken Littles" represent power players in an intractable political dynamic. The only way this kind of cooperation happens is when humans move past current notions of nation states and begin to think strategically as a species.

Not if an independent organization (think a Corp, not a gov) is the party responsable. They would have no incentive to do such a thing, in fact they would have a negative incentive.

Too bad nuclear tech is basically too regulated for any non governmental organization to experiment inexpensively, not to mention the other nontechnical issues.

Re: Nuclear Pulse Propulsion – Orion and Beyond (2000) [pdf]

#93

Post by [deleted] »

moseandre wrote: post #20
jharohit wrote: post #17

Earlier quoted context omitted.

I would rather classify that as "unfortunate". Yes there are obviously biological harms in radiation exposure but that is what science & engineering is for. We know the power of nuclear energy so in order to harvest it, the right thinking should have been like "How can we safely extract it so that it does harm people in the mix?" rather than "Oh its harmful to humans so obviously we should give up and not use it". Cu…

I'm not sure all of the opposition to nuclear research is about dangerous byproducts from the typical situation(s). It is about the improbable problematic situation which lead to exponential disaster that are scary, and, even if improbable, inevitable...

[deleted]

Re: Nuclear Pulse Propulsion – Orion and Beyond (2000) [pdf]

#94

Post by witty_username »

dogma1138 wrote: post #30
jharohit wrote: post #27

Earlier quoted context omitted.

don't think so. I am guessing you would need really strong magnetic fields to contain the anti-matter.

Magnetic fields aren't the only issue here. You won't be able to store large amounts of it since quantum tunneling will become a statistical problem.

Could you explain? How would quantum tunneling of antimatter be a problem?

The probability of quantum tunneling is exponential so adding a little more separation or reducing the energy can change the probability from 10^-1 to 10^-100.

Re: Nuclear Pulse Propulsion – Orion and Beyond (2000) [pdf]

#95

Post by jandrese »

maverick_iceman wrote: post #68
andygates wrote: post #33

Earlier quoted context omitted.

> nuclear is unfashionable at the moment It's more than that - this isn't just hippies, it's every major power on the planet. To fly Orion you have to put hundreds of nuclear explosives in orbit and pinky-swear that you're not going to use them to obliterate your enemies. Nobody is going to accept that. Orion's a fun paper rocket but will never be more. Engineers and they "yay nukes!" crowd will drag it out every cou…

Anything that can accelerate a starship to a velocity of ~0.1c can have devastating consequences if pointed to earth. Just like planes can be used to destroy skyscrapers. Chicken littles notwithstanding, having a much faster mode of transport is worth the risk.

On a side note, this is why Independence Day and other interstellar alien invasion movies don't make much sense. The amount of resources necessary to move between solar systems in an even slightly reasonable timeframe is orders of magnitude larger than what you need to obliterate all life on the planet in just a few seconds. The idea that you could meaningfully fight back against an interstellar traveler is silly.

Re: Nuclear Pulse Propulsion – Orion and Beyond (2000) [pdf]

#96

Post by maxerickson »

masklinn wrote: post #90
maxerickson wrote: post #88

Earlier quoted context omitted.

Indeed, I didn't understand why you thought I would suggest something pointless. I wasn't suggesting it. If you want to argue that crashing into the atmosphere would be an inevitable result of the trip, okay, but I don't understand what else it would have to do with my initial comment.

> If you want to argue that crashing into the atmosphere would be an inevitable result of the trip That's not what I'm arguing FFS, I'm saying that'd be the result of going with the fastest possible trip, which would still leave the target significant time to set up countermeasures. Here's the rest of the paragraph of my original answer since you apparently stopped at the first period: > If you want to actually deliv…

So why not build the countermeasure before you build it in Earth orbit? what's the difference then.

[deleted some pointless back and forth]

Re: Nuclear Pulse Propulsion – Orion and Beyond (2000) [pdf]

#97

Post by elsonrodriguez »

grkvlt wrote: post #91
elsonrodriguez wrote: post #78

Earlier quoted context omitted.

The Curiosity rover has driven 9 miles in a little over four years on Mars. The Lunar Rover that came with Apollo 17 drove 22 miles in a little over 4 HOURS. As it turns out, humans are the best robots.

Yes, but with my super-rover-transporter system, we can cover 5,400 miles in the same time, with the 600 rovers. I'm envisaging a sort of airbag deployment system (like pathfinder) coupled with a dispenser system that fires a rover out every few minutes as the ship orbits the planet, for optimal coverage.

But to what end? Bigger and better probes? Finer and finer data points?

We can send probes forever, but when do WE go?

My underlying point is that we have enough data to start making attempts at settling Mars, and once we're there, we'll do more science and exploration than any existing robot can. If you doubt that, then show me a robot that can perform an archeological dig on a fossil site without destroying half of the fossils.

Re: Nuclear Pulse Propulsion – Orion and Beyond (2000) [pdf]

#98

Post by dalke »

berntb wrote: post #57
grkvlt wrote: post #51

Earlier quoted context omitted.

Any mechanism that can propel a starship to 0.13c is going to make your day unpleasant if it is pointed at things you have a particular fondness for. Favourite pets, cities, aircraft carriers, that sort of thing.

It is a theoretical "can". :-) It will be a long time before anyone use a fraction of C inside the solar system. Interstellar flight is a problem after we have gotten to a reasonable cost/kg for both launching from the Earth and for interplanetary travel. I doubt there will be a pressing need for getting close to even 100 km/s in the inner solar system for decades. (Yes yes, "640K is enough for anyone". :-) ) (Consid…

"I doubt there will be a pressing need for getting close to even 100 km/s in the inner solar system for decades"

Quoting https://en.wikipedia.org/wiki/Solar_Probe_Plus :

> Solar Probe Plus or Solar Probe+, previously NASA Solar Probe, is a planned robotic spacecraft to probe the outer corona of the Sun. ... As the probe passes around the Sun, it will achieve a velocity of up to 200 km/s (120 mi/s) at that time making it the fastest manmade object ever, almost three times faster than the current record holder, Juno. ... Launch date: July 31, 2018 (planned).

Re: Nuclear Pulse Propulsion – Orion and Beyond (2000) [pdf]

#99

Post by TheSpiceIsLife »

IndianAstronaut wrote: post #29
jharohit wrote: post #15

Earlier quoted context omitted.

Exactly - i think there should be more companies & organizations working towards pushing this. To become space-faring, we need to get from 1ev per bond of molecule level of energies obtained from chemical to 1GeV levels atleast!

We are a long ways from becoming space faring. For the cost of sending one human to Mars, we could send ten rovers to Mars.

Cost of putting Curiosity on Mars: $2.5 billion

Apple and Google combined valuation: over $1000 billion

The trouble is there are no new users and new ad impressions to be found on Mars.

Re: Nuclear Pulse Propulsion – Orion and Beyond (2000) [pdf]

#100

Post by masklinn »

maxerickson wrote: post #96
masklinn wrote: post #90

Earlier quoted context omitted.

> If you want to argue that crashing into the atmosphere would be an inevitable result of the trip That's not what I'm arguing FFS, I'm saying that'd be the result of going with the fastest possible trip, which would still leave the target significant time to set up countermeasures. Here's the rest of the paragraph of my original answer since you apparently stopped at the first period: > If you want to actually deliv…

So why not build the countermeasure before you build it in Earth orbit? what's the difference then. [deleted some pointless back and forth]

Because there's no way you'll be able to detect the launch and deploy your countermeasures, even assuming said countermeasures actually work which is unlikely: it's doubtful we can counter ballistic missiles as-is, a payload starting from orbit can launch much closer to the target (rather than half a world away) and is not fighting gravity for half the trip.
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