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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]

#21

Post by flukus »

jharohit wrote: post #18
jaunkst wrote: post #14

If only we could produce anti matter. A tiny amount would provide a fuel source viable for deep space exploration.

Anti-matter is produced at CERN for study https://home.cern/topics/antimatter . The problem is not production of it but the economy of producing it. It's still very costly to produce and then to build and engine around it which uses the energy efficiently is still at least 10-15 years. But do believe that the time to start actively looking into it is NOW.

Is it stable enough to survive a space launch?

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

#23

Post by saulrh »

askvictor wrote: post #22

Eli5: how does a nuclear explosion create a change in velocity for the spacecraft?

Sort of like a sailboat, except the wind is the vaporized material from the nuke. The nuke explodes, throwing a ton of mass and energy in every direction. The rocket uses a sail or pusher plate to catch part of that mass and energy, which carries it forward.

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

#24

Post by avmich »

askvictor wrote: post #22

Eli5: how does a nuclear explosion create a change in velocity for the spacecraft?

The explosion throws the products of the explosion - mostly plasma - into all directions. The spaceship is nearby, so some of the plasma hits the ship, which is hiding behind a strong plate. Plasma transfers momentum to the ship.

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

#25

Post by jharohit »

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...

well you have rockets which blow up on launch sites. so..

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

#26

Post by wyager »

moseandre wrote: post #10

Please read Freeman Dysons's "Disturbing The Universe". This book is autobiographical and Dyson explains his arc of passion for nuclear propulsion and Orion. His strongest statement in this book is some deep respect for a biological scientist who, after seeing declassified army training manuals on chemical and biological warfare, supposedly discouraged the entire western hemisphere from further develomepment. This ki…

>This kind of nuclear research is, thankfully, over.

Nuclear pulse propulsion is the only currently viable technology that could be used to make humans an interstellar species. It would also allow us to practically ship up enough materials to build self-sustaining habitats in near space. It is extremely unfortunate that this kind of research is over.

Fun fact: the background radiation levels introduced by nuclear propulsion would actually have a very slight positive health effect on humans according to more accurate radiation hormesis models, rather than the very small negative effects suggested by more naive no threshold models.

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

#27

Post by jharohit »

flukus wrote: post #21
jharohit wrote: post #18

Earlier quoted context omitted.

Anti-matter is produced at CERN for study https://home.cern/topics/antimatter . The problem is not production of it but the economy of producing it. It's still very costly to produce and then to build and engine around it which uses the energy efficiently is still at least 10-15 years. But do believe that the time to start actively looking into it is NOW.

Is it stable enough to survive a space launch?

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

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

#28

Post by narag »

sillysaurus3 wrote: post #2

Happy to see this getting some attention. It's seemed like one of the only viable propulsion methods for interstellar purposes, though nuclear is unfashionable at the moment. I remember seeing a chart showing that it was possible to reach other stars using a technique like this. Unfortunately the problem is slowing down. You could get there, but you'd be going too fast to stop. And since the more fuel you carry, the…

I remember seeing a chart showing that it was possible to reach other stars using a technique like this. Unfortunately the problem is slowing down.

So this is like being concerned how you will spend all that money, once you make it :-)

There's a lot of discussion on interestellar travel, but "we" have almost frozen solar system travel. Yes, there are very nice probes out there doing important work, but manned vehicles are limited to keep ISS's lights on.

The "impossible" tech needed to reach the stars will most probably be discovered or refined while conquering the solar system.

Big sailing ships were developed along four centuries of sailing. The analogy may not be perfect, but I think it's eye opening.

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

#29

Post by IndianAstronaut »

jharohit wrote: post #15
sprucely wrote: post #11

Earlier quoted context omitted.

That's what Breakthrough Starshot[1] is about, although scaled down to very small probes. I like the probe concept. If we really don't want all our eggs in this one basket, it seems to make more sense to put effort towards tech that can spread our seeds (whatever that may be) rather than humans physically traveling. [1] https://breakthroughinitiatives.org/

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.

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

#30

Post by dogma1138 »

jharohit wrote: post #27
flukus wrote: post #21

Earlier quoted context omitted.

Is it stable enough to survive a space launch?

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.

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