[HN Gopher] Aldebaran 1959 Spacecraft Concept (2010)
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Aldebaran 1959 Spacecraft Concept (2010)
Author : LorenDB
Score : 58 points
Date : 2024-11-04 23:39 UTC (23 hours ago)
(HTM) web link (armaghplanet.com)
(TXT) w3m dump (armaghplanet.com)
| gary_0 wrote:
| (2010)
| imoverclocked wrote:
| This would be neat to see in space where the fallout wouldn't be
| an environmental issue. I have to wonder if anyone with
| significant credentials has considered a high-thrust nuclear ion-
| drive yet. Certainly sci-fi has!
| akira2501 wrote:
| > the fallout wouldn't be an environmental issue.
|
| "It's outside the environment."
|
| > has considered a high-thrust nuclear
|
| Of course we have. Always start at NTRS:
| https://ntrs.nasa.gov/citations/19690000736
|
| > Certainly sci-fi has!
|
| Our Solar system is a gravitational well that tends to put
| things in solar orbit. You really want the waste products to
| leave the solar system, which isn't terribly difficult, or you
| want them to land on the sun itself, which is exceptionally
| difficult.
| WillPostForFood wrote:
| _Our Solar system is a gravitational well that tends to put
| things in solar orbit. You really want the waste products to
| leave the solar system, which isn 't terribly difficult, or
| you want them to land on the sun itself, which is
| exceptionally difficult._
|
| Yes, it is counter intuitive but it takes less energy to
| leave the solar system get to the sun (you have to cancel out
| the Earth's orbital speed). Something learned from Kerbel
| Space Program.
| pmontra wrote:
| Time ago I read that the cheapest way to do it (energy
| wise) is going very far away, let's say entering Pluto's or
| Neptune's orbits, cancel out the orbital speed there (it's
| lower than Earth's one) and then fall into the sun. It
| takes quite a bit of patience.
| vikingerik wrote:
| Right, this is a bi-elliptic transfer, which is delta-v-
| cheaper than a Hohmann transfer for widely separated
| orbits. https://en.wikipedia.org/wiki/Bi-
| elliptic_transfer
|
| In practice in the real solar system, the cheapest way to
| get from Earth to the Sun is to use Jupiter. Launch to
| there and reverse-slingshot to cancel out the orbital
| velocity and drop directly towards the Sun. The Parker
| Solar Probe would have done this, although decided not to
| because of the complications in designing to handle both
| the cold of Jupiter and the heat of the Sun.
| adrianN wrote:
| I'm okay with waste products on an orbit that doesn't make
| them rain on Earth for a few dozen millennia.
| recursive wrote:
| Why would it be okay to rain the waste products on earth in
| a few dozen millenia. Do you think life will be over by
| then?
| aledalgrande wrote:
| Some visuals https://interestingengineering.com/science/project-
| orion-the...
|
| PDF in this article is a 404
| BrandonMarc wrote:
| See also this image from the article. The design of the
| Aldebaran is a giant flying boat, with air intakes in the wings
| to help create the nuclear exhaust exiting the reaction chamber
| nozzle.
|
| https://up-ship.com/blog/wp-content/uploads/2010/02/image25....
| caseyy wrote:
| What a time of dreaming big...
| kibwen wrote:
| Here's the famous XKCD radiation dosage chart for scale:
| https://xkcd.com/radiation/ . The highest scale in the
| chart, the yellow boxes, represents 50 Sieverts, of the
| dosage received from standing next to the Chernobyl core
| for ten minutes just after meltdown. A conservative
| estimate is that one launch on this thing would expose the
| crew to 5000 Sieverts, or 100 Chernobyls worth.
| Furthermore, we've sen how simple atmospheric nuclear
| testing irradiated the entire planet for half a century
| (see the Kodak film story and low-background steel), any
| prolonged use of this thing would have caused cancer rates
| to (ahem) skyrocket worldwide due to distribution of
| nuclear fallout into the atmosphere.
|
| Let's not romanticize stupid ideas. Leave this one in the
| dustbin of history.
| keyle wrote:
| Gorgeous. Maybe there is a universe...
| Animats wrote:
| Pictures of Orion concepts have been widely distributed for
| decades, but not this one. Going into space with an air-breathing
| nuclear bomb powered jet engine. That is truly weird. How fast
| was it supposed to be going in atmosphere, I wonder. Did it carry
| reaction mass for vacuum so it could keep going out of the
| atmosphere?
|
| The trouble with nuclear rockets is that although you have plenty
| of energy, you still need to carry reaction mass - air, or water,
| or something - and a lot of it. That becomes the limit on
| delta-V.
|
| (The great frustration of rockets: not only do rockets need
| something to push against, they have to carry it with them.)
| unwind wrote:
| Uh, is it really clear to say that rockets "push against"
| something? That makes it sound as if they could absolutely not
| work in space, which they obviously do.
|
| "They push against their own exhaust" seems to be the idea that
| motivates the pushing explanation, but to me that just invites
| the question "using what?" and makes things even more
| complicated. At least in my opinion.
|
| I think Newton's 3rd ([1], forces and reaction forces) is a
| better explanation.
|
| [1]: https://en.wikipedia.org/wiki/Newton%27s_laws_of_motion
| richrichardsson wrote:
| > rockets need something to push against, they have to carry
| _it_ with them.
|
| (Emphasis added)
|
| The rocket exhaust is "pushing against" the rocket itself,
| propelling it forward.
|
| Rocket exhaust goes <- which creates the equal and opposite
| force -> which pushes against the mass of the rocket sending
| it on its way.
| cryptonector wrote:
| > not only do rockets need something to push against, they have
| to carry it with them
|
| I think you meant "something to push _with_. But anyways,
| nuclear explosions make their own hot gasses out of the
| reactants, and the problem with that is getting that to be
| directed and also to not get the ship -you know- blown up in
| the process.
|
| A better approach is to have a nuclear reactor to heat reaction
| gasses to much higher temps than chemical reactions allow for,
| thus increasing ISP a lot. The main problem with this is that
| nuclear reactors need a lot of cooling, even and especially
| after you shut them off, and the reaction gasses are going to
| be your only way to cool them. Alternatively you can carry huge
| radiators -- really huge, because in space you don't get to
| exchange heat with an atmosphere or a body of water, so you can
| only radiate or ablate away the excess heat, and either way
| would require huge amounts of extra mass. Another problem is
| that stop/start latency with nuclear reactors is huge, so they
| would only work for interstellar travel, I think. I'm sure if
| you carry enough reaction mass then nuclear reactors can work
| well for interstellar trips.
| glompers wrote:
| By pushing against it they are pushing with it
| JKCalhoun wrote:
| The long _Discovery_ space craft depicted in the latter half of
| "2001: A Space Odyssey" was derived from the nuclear rocket. It
| was suggested that the radioactive part of an Orion-style space
| craft be put far away from the crew compartment.
|
| We can probably can thank Fred Ordway (Marshall Spaceflight
| Center engineer) who Kubrick brought on board as technical
| consultant back then. (And of course for the _look_ of the ships
| that are still so iconic over 50 years later I shouldn 't leave
| off Harry Lange.)
| rsynnott wrote:
| The 2001 spacecraft was implied to be a NERVA-type nuclear
| rocket (ie push working fluid through a high temperature
| reactor), rather than an Orion type (propulsion via small
| nuclear explosions).
|
| But yeah, "crew module, long thing, engine" was how these were,
| virtually always, depicted in sci-fi.
| TruffleLabs wrote:
| On Wikipedia "List of stories featuring nuclear pulse propulsion"
|
| https://en.wikipedia.org/wiki/List_of_stories_featuring_nucl...
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