Nuclear fuel for trans planetary travel  - Page 1
Forum section: electronics / general

author: MrOmnos
author_rank: Frequent Contributor
timestamp: December 19, 2016, 10:28:58 am
content: I watching a documentary on project Orion. Americans intended to build space ships powered by nuclear explosions and they seemed pretty damn serious about it. Both US and CCCP at some point were experimenting with nuclear aircraft which is quite stupid if you think about it now. The risk factor alone is not worth the endless flight hours which itself is limited by the aircraft compression and decompression cycles. But space travel using nuclear fuel makes sense. You get into orbit with your conventional rockets and then after maintaining a safe distance form the planet you fire up the nuclear engine. You are no longer at the mercy of gravitational assists from the planets to reach certain velocity nor you have carry massive amount of fuel. If SpaceX wanted to use similar contraption for their planned martian landings, would they be allowed to do so?

author: jonovid
author_rank: Super Contributor
timestamp: December 19, 2016, 10:30:49 am
content: explosions will also move you car too. but the large steel plate at the back of your vehicle, and the hazed to other road users. your fuel consumption is about one handgrenade pur meter and untold destructionspitting ionized particle in to the vacuum of space may work with the nuclear as the electrical generator. a bit slow as you start out so conventional rockets got you up to speed. then let the ionized particle jet or ion thruster take over. ion thruster powerd from a nuclear electrical generator or romashka reactor family useing uranium and direct thermoelectric conversion to electricity.then what would i know about rocket science.5 edits later

author: MrOmnos
author_rank: Frequent Contributor
timestamp: December 19, 2016, 10:41:20 am
content: Quote from: jonovid on December 19, 2016, 10:30:49 amAmericans actually did the maths and had designs that would make it possible for the ships to withstand the blasts. Here the wiki articlehttps://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)

author: magetoo
author_rank: Frequent Contributor
timestamp: December 19, 2016, 01:46:41 pm
content: If anyone is interested and wants to read more,Atomic Rocketsis where it's at. Everything from real, in-use rockets, to cancelled projects and crazy hypothetical sci-fi designs with plausible physics (and implausible ones too).

author: strangersound
author_rank: Regular Contributor
timestamp: December 19, 2016, 02:09:03 pm
content: Deep space missions, such as Cassini, use nuclear fuel (radioisotope thermoelectric generation/RTG) to produce electricity to power electronics, due to the fact that a mission to Saturn is too far from the Sun to use solar arrays since they would be too large and heavy.Plutonium of various types has been a major source of power for space missions for some time. Not in the sense of the question you ask, but used as a source of power none the less that without it, these long range missions would not have been possible. Voyager recently started to exit the solar system and would not be able to transmit data over a 40 year period without nuclear power.From what I've seen in one article, NASA and other related entities are actually concerned about the future availability of plutonium and related isotopes, without which they would not be able to conduct these exploratory space missions. So, I doubt they would consider trying to switch from traditional fuel loads to use for propulsion needs (altering trajectories, etc) when it seems from the limited stuff I've read that the primary use for nuclear fuel is RTG. With the combination of selected engine firing with traditional fuels loads and manipulation of gravitational fields, they are able to do a pretty good job at getting a spacecraft where they need it. The fact they could get a vehicle in orbit around Titan (one of Saturn's moons) and then do repeated dives through Saturn's rings multiple times before eventually plunging the craft into the surface of Saturn using fairly traditional means blows my mind.I literally just watched this documentary last night about Cassini (posted below), so I wouldn't have even been able to gives some of my two cents to this thread had I not. Because that of course led me to digging into some other related info that is sort of related to your question.

author: Seekonk
author_rank: Super Contributor
timestamp: December 19, 2016, 04:01:18 pm
content: IIRC those atomic aircraft had the crew breathing oxygenated water as it was the only way to shield them. Adds new meaning to don't pee in the pool.

author: Benta
author_rank: Super Contributor
timestamp: December 19, 2016, 04:45:51 pm
content: QuoteFor RTGs, it's the availability of one specific isotope,238Pu, which is extremely scarce and not found in nature. It is a by-product from nuclear fission, but in extremely small amounts. The last figure I read, around 30 kg is available to the US/NASA, which is enough for three missions only.There was an extremely interesting article on this subject on wired.com a couple of years back, unfortunately I haven't been able to find it again.

author: strangersound
author_rank: Regular Contributor
timestamp: December 19, 2016, 04:51:17 pm
content: Quote from: Benta on December 19, 2016, 04:45:51 pmWell, you're in luck, because that's likely exactly where I read it. Is this it?https://www.wired.com/2013/09/plutonium-238-problem/

author: Benta
author_rank: Super Contributor
timestamp: December 19, 2016, 06:52:43 pm
content: QuoteYes, that's the one, Thank You.My search was probably frustrated by the "ad-blocker-blocker" policy now in force at Wired, where even allowing wired.com doesn't work. I'm experiencing this on several sites.

author: strangersound
author_rank: Regular Contributor
timestamp: December 20, 2016, 05:44:34 am
content: Quote from: Benta on December 19, 2016, 06:52:43 pmI'm using uBlock Origin, which I've found to work a lot better and doesn't seem to cause the type of problem you had. I am running it now and I opened that page before I grabbed the link and replied and the page loaded just fine. They claim that uBlock is less resource hungry than adblock/adblockplus. I can't verify that, but I can say that uBlock was the only one that has been able to combat Facebook's continuing efforts to shove advertising in the news feed.Just to be sure, I just opened Wired's home page. Loaded just fine, no ads. I'd suggest ditching whatever browser plug-in you're currently using and try uBlock Origin.

author: Benta
author_rank: Super Contributor
timestamp: December 20, 2016, 11:33:12 am
content: Good tip, I'll try that.Thanks.

author: Benta
author_rank: Super Contributor
timestamp: December 20, 2016, 05:48:14 pm
content: Ha! Deinstalled adblock plus, installed ublock origin.I can now read wired.com again!Thanks!

author: strangersound
author_rank: Regular Contributor
timestamp: December 20, 2016, 09:41:43 pm
content: Quote from: Benta on December 20, 2016, 05:48:14 pmRock and roll!I would like to encourage people who choose to use adblocking software to whitelist sites they truly benefit from, such as Dave's, etc. In addition, most YouTube creators make a pretty good business supporting their endeavors with t-shirts, stickers, and other merchandise. There's Patreon, as well. The more we directly support artists and content creators, the less the have to rely on advertising. And who really wants to feed those clowns? They're just a parasite playing middlemen profiting off the work of others. Like a record label.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 21, 2016, 02:59:19 am
content: Quote from: strangersound on December 20, 2016, 09:41:43 pmAdblock Plus has a built in whitelist ("acceptable ads"), although users do have the option to disable it. If I come across a site that refuses to work properly with that, I often find that a carefully timed F5 and ESC breaks the "adblock breaker". (In other words, "I don't block acceptable ads, so make your ads acceptable if you don't like me blocking them. Until then, I'll happily drive up your bandwidth costs breaking your adblock breaker.")