Is Science Fiction Losing Its Charm Due to Unrealistic Space Travel?

[Ryan_m_b]

Ok, thank you.

(And again, sorry for our previous misunderstainding. :( I should have made it clear that I imagined the orbital craft to operate in a wider orbital belt, so it could observe and attack more, gradually modificating course during turn around the planet, and by capture, i meant, force to surrender by lethal threat. )

No worries. But do go and look into how orbit works. It's vastly different to any medium on Earth with the speeds, distances and vacuum making zipping around like any terrestrial transport impossible.

 

[GTOM]

I read about orbital mechanics, i think its a must have to SF writers (who want to deal with space).
Yes an inclination change isn't something that can be taken lightly...
Although i saw methods that could make that easier.

1 : scratch the stratosphere, then ascend
2 : take an elliptical path, and change inclination at apophis, where speed is smallest
3 : use recoilles stuff, like magnetic fields in the magnetosphere

I wonder whether magsails could take over rockets, if big acceleration isn't needed?
(Since there arent confirmed progress with anti gravity, space time warp, sails are the only recoilles methods. )

 

[Vierstein]

Moderation note: This thread has been split from another so as not to derail the former thread

I have a hard time enjoying Star Wars anymore because of how those spaceships fly around :(

What you don't like the sound they make in space?

VRROOOOMMM XD

 

[Traz 0]

I'm not sure which of the split threads this belongs in, but ...

Footfall, by Larry Niven and Jerry Pournell had what seemed to me at the time (1985) to be some very well thought out space combat. Human versus alien, where the aliens have superior tech but we have desperation. We launch a supermassive Orion-type carrier ship (from Earth ... Desperate!) accompanied by a fleet of shuttles. The primary weapons used are x-ray lasers pumped by the orion drive. The aliens are dumbfounded by the reckless tactics.

Niven and Pournell are famous for hard SF, and if I recall correctly, Pournell worked on a real life space-based kinetic weapon system which was never deployed (or was it? ;-) ) called Thor or Thads ...

 

[Traz 0]

I just realized that I didn't define the Orion drive. Project Orion was a real life proposal to propel a spacecraft by exploding nuclear bombs behind a pusher plate. I suspect that it would be a bumpy ride ...

 

[ImaLooser]

I just realized that I didn't define the Orion drive. Project Orion was a real life proposal to propel a spacecraft by exploding nuclear bombs behind a pusher plate. I suspect that it would be a bumpy ride ...

I remember that. One of the scientists involved in launching a small chemical prototype said, "This is not nuts, this is supernuts."

 

[Traz 0]

I remember that. One of the scientists involved in launching a small chemical prototype said, "This is not nuts, this is supernuts."

Well, I certainly wouldn't want to live downwind of a surface launch.

As far as a Project Orion space drive, I suppose that its feasibility is partially an engineering problem, and partially political, i. e., who would I trust in possession of hundreds of nukes in space, how they could be secured, etc. Barring an alien invasion or a dino-killer space rock with our name on it, my vote would be, uh, no thanks.

 

[Traz 0]

No worries. But do go and look into how orbit works. It's vastly different to any medium on Earth with the speeds, distances and vacuum making zipping around like any terrestrial transport impossible.

From the Robert Heinlein wiki:

Heinlein himself stated - with obvious pride - that in the days before pocket calculators, he and his wife once worked for several days on a mathmatical equation describing an Earth-Mars rocket orbit, which was then subsumed into a single sentence of the novel Space Cadet.

 

[Ryan_m_b]

From the Robert Heinlein wiki:

Heinlein himself stated - with obvious pride - that in the days before pocket calculators, he and his wife once worked for several days on a mathmatical equation describing an Earth-Mars rocket orbit, which was then subsumed into a single sentence of the novel Space Cadet.

I'm not sure how that applies to the quoted sentence...

 

[Traz 0]

I'm not sure how that applies to the quoted sentence...

and previously (I don't know how to multi quote on my phone):

GTOM said, roughly:

"I read about orbital mechanics, I think it's a must have for science fiction writers ..."

See, my point was, Robert Heinlein, a pretty famous science fiction writer, seems to have agreed with both GTOM and you about orbital mechanics vis a vis SF writing, in a time when doing so took a lot more work.

I thought the thread I was following there was pretty clear ...

 

[Riemann Metric]

Well, I certainly wouldn't want to live downwind of a surface launch.

As far as a Project Orion space drive, I suppose that its feasibility is partially an engineering problem, and partially political, i. e., who would I trust in possession of hundreds of nukes in space, how they could be secured, etc. Barring an alien invasion or a dino-killer space rock with our name on it, my vote would be, uh, no thanks.

I'm sure there are many elegant solutions to space travel than blowing up a bunch of bombs behind a plate to launch a spacecraft at high speed-take solar sails or magnetic acceleration cannons/mass drivers, for instance. The only issues we have with these are slow acceleration+microasteroids vs. tremendous forces and huge momentary accelerations.

 

[Traz 0]

I'm sure there are many elegant solutions to space travel than blowing up a bunch of bombs behind a plate to launch a spacecraft at high speed-take solar sails or magnetic acceleration cannons/mass drivers, for instance. The only issues we have with these are slow acceleration+microasteroids vs. tremendous forces and huge momentary accelerations.

I'm sure there are more elegant solutions too.

In the novel<I> Footfall </I>, the problem to be solved wasn't spaceflight, per se. The invaders had occupied Earth, had surveillance ships in orbit, and a giant, well-protected mothership that was all but invulnerable. Engaging the enemy required a truly massive ship of our own that could sustain a great deal damage from kinetic and directed energy weapons. It also had to be built in secret, on earth, in a hurry, without a research program or orbital construction.

As far as stopping a dino-killer rock in a hurry, it's not inconceivable that we might have to substitute quick and dirty for elegant in certain scenarios. It certainly happens in the real world.

In 1992, I was managing a project to convert a government agency's antiquated applications and data to modern hardware, and there were a number of files that were weird for some reason I can no longer recall. I diagramed as general algorithm that could read any such file and create the data structure and conversion code needed, and gave it to a programmer. Rather than write that application, he looked at the files, found there were only 20 or so unique types, and wrote 20 or so separate programs. I have a strong preference for elegance in all things, and his solution pissed me off. But. The project had been underbid, we were behind schedule, and every day late cost my company money. His way <I> was </I> faster, and assuming we never needed to do the same type of conversion again, better.

Still, I'm not advocating <I> Project Orion</I> as a space travel solution, by any means, and I hope it didn't seem like I was.

 

[Riemann Metric]

Well, who knows...maybe something that seems unorthodox like Project Orion could inspire something that really does work. As it is said, necessity is the mother of invention, and I fear our efforts towards something we think we don't need will be rather negligible until our views change.

 

[lpetrich]

Isaac Asimov, in "Future? Tense!" from From Earth to Heaven described how a science-fiction writer in 1880 might write stories involving cars.

"The automobile came thundering down the stretch, its mighty tires pounding, and its tail assembly switching furiously from side to side, while its flaring foam-flecked air intake seemed rimmed with oil." Then, when the car has finally performed its task of rescuing the girl and confounding the bad guys, it sticks its fuel intake hose into a can of gasoline and quietly fuels itself.

While a car as a mechanical horse seems almost too silly for us to take seriously, lots of visual-media science fiction has similar absurdities about its spaceships.

I recall when Gene Roddenberry was once asked about some of them, like never seeing spaceships upside down. He responded that that was to avoid unnerving an Earthbound audience, and that's why explosions in outer space make sounds. A soundless explosion is correct, but it would make many watchers wonder what happened to their TV's' sound.

Some Star Wars battleships look more like they could be floating than flying, with a hull and a superstructure on one side of it, the crewmembers' upward direction.

A lot of the space combat in the Star Wars series looks like it could have come out of WWI and WWII dogfights -- the fighter spaceships behave too much like airplanes.

IA also imagined:

There could be the excitement of a last-minute failure in the framistan and the hero can be described as ingeniously designing a liebestraum out of an old baby carriage at the last minute and cleverly hooking it up to the bispallator in such a way as to mutonate the karrogel.

Some Star Trek episodes are full of that sort of thing, something that some fans and critics have named "treknobabble".

 

[GTOM]

Can we return to recon a little bit?

Ryan you said, that a really big battleship could carry a neutrino detector.
I read that a neutrino can easily go through the entire Earth.
Ok, you can determine whether something with a reactor is close or not, but can you possibly get any accuracy needed to target?

While you can't become invisible in space, how about a smoke screen like application, once you don't need to use the thrusters (you might still be able to do a tiny course change with magnetic fields), sorround your ship with black canvas, metallic nets, chaff? You don't have to be in the middle of this. Yes they will know roughly where you are, but i almost hit it is unsatisfactory... Probably you don't have a second chance to fire, or offer a barrage strong enough.
The concealed one could still see with small outside probes.

Also planetary defences have much better options to conceal a cannon, or orbital craft can redirect its waste heat toward the planet.

 

[Ryan_m_b]

Ryan you said, that a really big battleship could carry a neutrino detector.
I read that a neutrino can easily go through the entire Earth.
Ok, you can determine whether something with a reactor is close or not, but can you possibly get any accuracy needed to target?

Sure neutrinos fly through the Earth and a lot more. But detectors can snatch a tiny percentage of them because a very small number will, statistically speaking, hit an atom.

While you can't become invisible in space, how about a smoke screen like application, once you don't need to use the thrusters (you might still be able to do a tiny course change with magnetic fields), sorround your ship with black canvas, metallic nets, chaff? You don't have to be in the middle of this. Yes they will know roughly where you are, but i almost hit it is unsatisfactory... Probably you don't have a second chance to fire, or offer a barrage strong enough.
The concealed one could still see with small outside probes.

Also planetary defences have much better options to conceal a cannon, or orbital craft can redirect its waste heat toward the planet.

There's no stealth in space because your craft will be vastly hotter than the background. If you've got a power source like a nuclear reactor it means that your craft is going to have a spot in it hundreds of degrees hot. Even just at zero degrees C you will be hundreds of degrees hotter than the background.

This is a good article on the subject: http://www.projectrho.com/public_html/rocket/spacewardetect.php#nostealth

 

[GTOM]

"This is a good article on the subject: http://www.projectrho.com/public_htm...php#nostealth"

I read it already. But i didnt intend to hide my vector.

"sorround your ship with black canvas, metallic nets, chaff? You don't have to be in the middle of this."
"Yes they will know ROUGHLY where you are, but i almost hit it is unsatisfactory... "

"If you've got a power source like a nuclear reactor it means that your craft is going to have a spot in it hundreds of degrees hot."

So I sorround the ship with a light weighted, but opaque canvas. It will be heated all around to a pleasent degree. So where is the ship exactly in a large (but light) cube? Where should you aim if you want to actually hit it?

Of course it will the transparent to neutrinos (and i have to send out at least recon stuff communicating with wires).
But putting a neutrino detector to a battleship?
http://en.wikipedia.org/wiki/Sudbury_Neutrino_Observatory
And you have to shield it from your own reactor if you don't run with chem fuel.

Well, I don't really think this is viable, but at least it will be pretty hard to build such a spacecraft .

 

[Ryan_m_b]

So I sorround the ship with a light weighted, but opaque canvas. It will be heated all around to a pleasent degree. So where is the ship exactly in a large (but light) cube? Where should you aim if you want to actually hit it?

Aside from the problem of how do you see where you're going now there are going to be hotspots suggesting where you are. Even if not I can't see you dragging around a big enough canvas than an enemy couldn't just shoot a missile through that has a shaped charged and is smart enough to quickly locate you and explode in that direction.

Of course it will the transparent to neutrinos (and i have to send out at least recon stuff communicating with wires).
But putting a neutrino detector to a battleship?
http://en.wikipedia.org/wiki/Sudbury_Neutrino_Observatory

Lol you're talking about huge military spacecraft with nuclear reactors and you have a problem with fitting a neutrino detector in if you're handwaving away the technical difficulties of the former you should at least be consistent with not handwaving away other difficulties.

Besides which looks like there are efforts to shrink the size of detectors:
http://minnesota.publicradio.org/display/web/2010/07/13/university-of-minnesota-neutrino-detector

 

[GTOM]

" if you're handwaving away the technical difficulties of the former you should at least be consistent with not handwaving away other difficulties."

I carried a tent many times but not a rad suit (shielding from your own reactor).

Otherwise OK i just surrender.
Thanks for the article Ryan, it is always good to read about new developments. :)

 

[GTOM]

" http://www.projectrho.com/public_htm...php#nostealth "

"The maximum range a ship running silent with engines shut down can be detected with current technology is:

Rd = 13.4 * sqrt(A) * T2

where:

Rd = detection range (km)
A = spacecraft projected area (m2 )
T = surface temperature (Kelvin, room temperature is about 285-290 K)

If the ship is a convex shape, its projected area will be roughly one quarter of its surface area."

An example : http://en.wikipedia.org/wiki/Chelyabinsk_meteor

"The United States space agency NASA estimated the diameter of the bolide at about 17–20 m and has revised the mass several times from an initial 7,700 tonnes (7,600 long tons; 8,500 short tons),[10] until reaching a final estimate of 10,000 tonnes"

Ok. Diameter 17m, radius half.

A ~ (17/2)^2*pi ~ 227m2 (*4 /4)

Surface temperature : (average lunar temperature?) 250 K

So Rd = 12 617 655 km...

If i decrease surface temperature to 40K (lunar minimum) it is still 323 026 km, Earth to Moon range.
And they can browse the whole sky in 4 hours...

"The Chelyabinsk meteor was a near-Earth asteroid that entered Earth's atmosphere over Russia on 15 February 2013 at about 09:20 YEKT (03:20 UTC), with an estimated speed of 18.6 km/s "

If i ignore speed gained by Earth'as gravity, just multiply 18,6 with four hours, it is still below that claimed distance.

What did i miss? They missed the meteor, there wasnt last minute warning, please get away from the windows.

 

[schonovic]

Yes you are totally right. I am a big fan of fantasy and sci fi and space fantasy (of which there is a LOT in more recent years)

Sci fi in films and books is in decline as we increasingly realize how unlikely anything along them is.

I think we should not be so easily convinced that space travel is unlikely. I mean Einstein did say "NOTHING EXCEEDS THE SPEED OF LIGHT, HOWEVER THERE ARE NO ABSOLUTES" Did he mean no absolute speed of light, no absolute time? I think we are just not seeing the mystery in his math. I'm still hopeful that there are ways that we just aren't aware of that could take us to space on the large scale.