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9269972 No.9269972 [Reply] [Original] [archived.moe]

How come we haven't yet built small, manoeuvrable spaceships yet which can just fly around the solar system?

Surely with current technology (e.g. ion propulsion) this is definitely possible?

>> No.9269975
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9269975

>> No.9270006

>>9269972
>Surely with current technology (e.g. ion propulsion) this is definitely possible?
By saying this it shows that you don't really understand current technology.

I suggest doing some research. Try something other than movies and their in-universe encyclopedias.

>> No.9270007
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9270007

>>9269975
That's not an answer

I guess you could say maybe there's no need for such a ship - if you want to check out a planet, then sending a probe is much cheaper, and also doesn't risk human life

So I guess it's probably a question of economics - just like it's rare to have single-passenger ships crossing the Atlantic. To create a ship capable of making such a journey, but which only carries one passenger, is pretty uneconomical.

Still, I reckon we *COULD* build a spaceship that can just fly around if we wanted to. Why isn't some rich guy paying someone to build such a thing? It would be the coolest thing to show off wouldn't it?

>> No.9270149
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9270149

>>9270006
>doesn't have an argument
I don't care if ion propulsion has incredibly low thrust, the point is that the fuel lasts for fucking ages

>> No.9270167

Real life isn’t Star Wars,what would be the point in a small compact ship when it takes months/years to get anywhere in our solar system ?

>> No.9270196

>>9269972
>solar system

We can barely get small manoeuvrable spaceships which can just fly around earth. Soyuz can't even do lunar flybys.

>> No.9270408
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9270408

>>9269972

Play Kerbal, which is very, very lenient with DV requirements.

Just getting a single stage bird to orbit is a feat. Putting it on a rocket and sending it up, will give you enough DV to get to the moon and back at most.

X-37 is our realistic "starfighter", and it needs a rocket launch to get it into orbit for it to do its orbital missions.

>> No.9270466

>>9270408
>Just getting a single stage bird to orbit is a feat. Putting it on a rocket and sending it up, will give you enough DV to get to the moon and back at most.
I understand this, but you could launch something into space with a rocket, and then it could use ion propulsion to navigate around space.

Like I said here - >>9270149 - I understand that ion propulsion has pretty low thrust. And yes I suppose that means that manoeuvrability isn't really something it allows that much.... it is mainly intended just to travel in a straight line, because even though its thrust is small, it can reach high speeds due to conservation of momentum.

I dunno whatever - I'm sure it would be possible to make a manoeuvrable vehicle for flying around space if someone really wanted to, but like I said here - >>9270007 - I guess a probe is cheaper for nearly every kind of mission. You just send the probe on a trajectory for the planet you want to check out, and it travels on its way. Changes in speed and changes in direction not really needed.

>> No.9270489

>>9269972
Space flight is a lot harder than it looks, and a "maneuverable" ship would probably have a weak delta v budget for it's mass. Ion propulsion isn't strong but highly efficient. In space travel maneuverability is only important for launch so you can maintain control. Everything else is about efficient and gradual course changes.

>> No.9270496

>>9270489
To add to this, your agile space fighter would be very maneuverable for about 2 minutes before you ran out of propellant. The technology just isn't there yet, and may never be. There are barriers when it comes to chemistry and physics.

>> No.9270507

>>9269972
>what is gravity
back to school retard

>> No.9270526

>>9270496
I posted a NASA paper on space battlecruisers yesterday, it's possible. Basically you have to use beamed propulsion because as others have said maneuvoureing with thrusters your fuel will run out very fast.

>> No.9270720

>>9270149
I have an argument and it is that current technologies can't do what you are talking about.

Now do some fucking research.

>> No.9270789

>>9269972
What is every craft we've sent beyond Earth's orbit? You don't make general-purpose manned craft, that's retarded and pointless.

>> No.9270840

>>9270196
>Soyuz can't even do lunar flybys.

actually it can, Soviets even did a lunar flyby with a Soyuz back in 1968
https://en.wikipedia.org/wiki/Zond_5

>> No.9270866

>>9270149
You need high specific impulse and high fuel economy for what you want. We dont have both at once yet.

>> No.9270869
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9270869

>> No.9270900

>>9270866
Specific impulse and fuel economy are the same thing in space. You mean high thrust with high specific impulse.

>> No.9270901

>>9270866
>>9270869
one last thing, You need higher G acceleration than the influence of gravity from the Sun, otherwise you'll be forced to just "go with the flow" Ion thrusters don't have this. It would be like trying to paddle against the current of a river with a spoon.

>> No.9270905

>>9270901
Well you don't really need it to maneuver like a starfighter, because that is just quick changes in relative velocity.

>> No.9271228
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9271228

>>9270840
This, among other things, blows out of the water the claims that "The Soviets never really wanted to go to the moon at all, the Americans were in a race by themselves." They had made unmanned tests of lunar flight with their spacecraft.

>> No.9271272

>>9271228
That and the existence of the N1.

>> No.9271285

>>9271272
The N1 was more designed for Mars/Venus though.

>> No.9271302

>>9270149

it's all about delta v my man. to go places you need to be able to change your speed. go get into orbit you need to be able to speed up to ~8 km/s. go to go the moon and back you need to be able to change your velocity as much as 15 km/s. and that's taking as much advantage as possible of orbital mechanics, which would take three days to get to the moon. speeding up the trip requires more of an ability to change your velocity.

>> No.9271344
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9271344

>it's an "absolute fucking clueless retard that knows nothing about science and physics fantasizing about some stuff he saw in a fucking sci-fi movie" episode again

>> No.9271736

>>9269972
Propulsion is not the problem.
The human body is.
Space is bad to the body.

>> No.9272620

>>9269972
The dawn spacecraft isn't much bigger than an X-wing is supposed to be. So yeah we jave small maneuverable spacecraft that can fly arouns the solar system.

We just can't put people in them.

>> No.9272738

>>9269972
Any modern propulsion which can allow ships to maneuver like Star Wars ships would require so much fuel that it wouldn't be able to do it for long. Mass x speed is propulsion, ion engines require a metric shitload of power for a measly acceleration and everything else can only be boosted so far. Chemical-based stuff is really the best option, but you could use all your fuel supplies in under a minute if you set the throttle to as fast as the movies.

>> No.9272746

>>9269972
>Why haven't we built something that would be incredibly expensive and have no real application?
Hmm, I wonder.

>> No.9272907
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9272907

>>9269972

go play kerbal space program

also I like how the A-wing resembles the X-38

>> No.9273059

>>9270466

You can get it to move around in space with ion engines, but you'll be stuck to orbits all the same. You'll be able to change your orbital "height", you'll be able to escape Earth and head to the moon and stay there or come back, and perhaps even the other planets if you've got enough DV.

Flying in space ain't like dusting crops. It's all about gravity and how much change in velocity you can produce to interact with the gravity emitting objects. It's actually just like dusting crops now that I think about it, just that you need inertial thrust.

>> No.9273061

>>9273059
>inertial thrust

I should say, reaction thrust for an inertial environment.

>> No.9273065

>>9272907
>X-38

I like to think the X-37 has the ability to carry anti-satellite Sidewinder/AMRAAM analogues in its payload bay.

I bet the latest X-37 mission is watching the new NK satellites.

>> No.9273087

>>9273065
The X-37 is probably testing tech the air force wants to test without having to go through NASA. Shit that you'd want to test in space and have back on the ground to see how well it worked. Also maybe precision maneuvering. Getting up close to 'non-cooperative objects' has important applications for satellite maintenance and military dick waving.

Using it for ASAT missiles would be silly. ASAT missiles can be launched suborbitally with fighter jets. This is a heck of a lot cheaper than putting them in orbit.
https://en.m.wikipedia.org/wiki/ASM-135_ASAT
Using sidewinder missiles for ASAT is even sillier, sidewinder missiles are aerodynamically stabilized. Look up rollerons some time they are cool.

North Korea's satellites are a fucking joke. They have been observed to be tumbling. This means they can't even get attitude control right.

Now it has been suggested that the X-37 has been used to spy on China's space station.

Bit it could also just be for military dick waving. Just showing that the US can wave their dick around in space on a short notice.

>> No.9273089

How does this even make since when the earth is flat and there's no space and NASA has been lying

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