Realistic Space War

[daniel l.]

In my opinion as an optimist towards tech. I believe that FTL will be invented within 1000 years of now. The battles you describe are extremely long range, Such warships would be highly vulnerable to a ship jumping in at point blank range and blowing it up with short range weapons like cannon turrets. The long range vessel would have no defense as it was never designed to handle close range combat.

Eventually both sides would develop FTL and it would no longer be a matter of long range sniping, Instead it will be ships detecting each other on LIDAR and jumping in point blank to ensure that no shot misses, Like this.

Pretty cool huh?

[Kryten]

On 4/15/2016 at 8:56 PM, Frozen_Heart said:

A realistic space war would be spy satellites being shot down by ASAT weapons. That is as far as we've got so we can't really guess any further.

The Chinese tested one a couple years back that could probably reach GSO, so now we can add communications and probably navigational sats to that list.

[Frozen_Heart]

1 hour ago, daniel l. said:

In my opinion as an optimist towards tech. I believe that FTL will be invented within 1000 years of now. The battles you describe are extremely long range, Such warships would be highly vulnerable to a ship jumping in at point blank range and blowing it up with short range weapons like cannon turrets. The long range vessel would have no defense as it was never designed to handle close range combat.

Eventually both sides would develop FTL and it would no longer be a matter of long range sniping, Instead it will be ships detecting each other on LIDAR and jumping in point blank to ensure that no shot misses, Like this.

Pretty cool huh?

Just give the missile ftl, it jumps into the target and destroys it from a solar system away and it can't dodge.

[Bill Phil]

23 hours ago, kerbiloid said:

Most satellites are less hardened than military equipment.

Unless they're military satellites.

Badum tss.

But if there's a real threat like that then they'll harden their sats.

[tater]

Within a fairly long range (by current standards) directed energy weapons can't miss. The target needs to be able to move a ship randomly a cross-sectional radius (from the POV of the shooter) during the time of flight of the weapon for there to be a chance of a miss. For weapons moving at or near c, this is a pretty long range, it need not look anything like bad SF movies with the ships closer than WW1 battleships would engage.

On the subject of WW1 battleships, Jutland shows the problem with any large warships vs weapons capable of destroying their target with a single hit, as the RN battlecruisers discovered in that battle.

 

[Bill Phil]

16 hours ago, todofwar said:

If a new colony, like Mars, was trying to gain independence I wonder if their best move would be to trigger Kessler syndrome and lock up the earth for a while 

LEO Kessler resolves itself within a short period of time, and higher altitude kessler, such as in GEO, can be avoided by launching on an inclined trajectory.

[tater]

Martian colony declares independence.

Earth stops sending them supplies.

Martians die.

The End.

 

[daniel l.]

6 hours ago, Frozen_Heart said:

Just give the missile ftl, it jumps into the target and destroys it from a solar system away and it can't dodge.

FTL is not precise as shown frequently, Whenever a Basestar jumps in it is generally out of weapons range and has to approach, Also the locking system of a missile would be disoriented by the jump, And could easily be countered.

Besides a missile would have to be very large and heavy in order to have FTL, Such a missile would be hard for Point defense to miss.

Edited April 17, 2016 by daniel l.

[tater]

That's BSG, right? They have numerous small craft that are SSTOs from Earthlike worlds, and they never seem to have any fuel problems to speak of... It's safe to say the smallest craft in the universe has well north of 20 km/s dv. That gives the craft 50X its total mass in TNT worth of energy (200 MJ/kg). That goes up with the square of the velocity, so what's the total dv of a small craft?

[Frozen_Heart]

5 hours ago, daniel l. said:

FTL is not precise as shown frequently, Whenever a Basestar jumps in it is generally out of weapons range and has to approach, Also the locking system of a missile would be disoriented by the jump, And could easily be countered.

Besides a missile would have to be very large and heavy in order to have FTL, Such a missile would be hard for Point defense to miss.

So now we know the properties of this so called ftl drive as well? If it is ever invented then we have no idea how large it will be, how much power it will take, how accurate it is, or how it would affect sensors. Aslo there is no garuntee that a jump drive could cancel relative velocities, so you could appear next to them then a single second later be 10km away.

 

All I can quite comfortably predict is that spacecraft battles will never be done broadside with cannons like the movies.

[KerikBalm]

11 hours ago, daniel l. said:

In my opinion as an optimist towards tech. I believe that FTL will be invented within 1000 years of now.

Sorry, but your beliefs for which you have no rational basis are not relevant to the subject of realistic space war.

Realistically... low orbit is a very dangerous place ot be if there is an industrialized society. Your craft will stand out like a torch in the night, while their installations will be very hard to distinguish.

A warship in space may have a powerful X ray laser, but an earth like planetary atmosphere will block that pretty well. You'll need to lengthen the wavelength to at least UV to hit targets on the surface. Although this might not be such a problem if your laser is a FEL, which can be configured for different wavelengths

Meanwhile, ground based installations can already be optimized for shooting through the atmosphere. Underground systems with just the laser aperature that would be revealed when firing... they could blind your ship at long range, and blow it up in low orbit. Similar underground installations could include missile silos, mass drivers, etc.

Sitting in low orbit is just waiting for something to pop out of nowhere and snip you. point defense systems may shoot down missiles... but they'd have a much harder time against mass drivers/railguns. Lasers... well, the atmosphere works for and against you... as they won't be X ray lasers, nor focused gamma rays, but UV or lower... Mirrors start to be possible... but still quite unrealistic as slight imperfections would ruin the whole thing.

Then there's the issue of distinguishing "civilian" stuff in orbit from military stuff.

Detecting objects is easy in space... there's no "stealth"... but if theres a bunch of other stuff, it can be hard to tell what stuff is a threat, and what is not.

You could "sanitize" the planets orbit from afar (such as deorbiting the stuff by ablation with a laser, like some solutions to space junk that have been proposed), then move in closer if you are willing to wipe out all orbital infrastructure.

With a sufficient focusing array (lets say 50m diameter), and petawatt outputs(already achieved on earth) coupled with gigajoule pulses (not achieved to my knowledge), and a wavelength in the X ray range... you could have a very very very long range laser... on for which measuring in AU is easier than meters (even if its 0.2 or 0.4 AU). Put a big enough one of these on the moon, and a couple times every few years you could start hitting targets around mars (maybe even on it... I'm not sure how much protection its atmosphere gives it) ... while jupiter would be quite out of reach. One could imagine "island hopping" building such installations on bodies to get closer and closer to your target... but this seems rather inefficient given that a missile will get there.

Missiles with nukes... perhaps later... missiles with antimatter.... and that lends itself to just kinetic energy weapons... why send a ship, when you can send a missile at 0.2c at the target, 0.4c? 0.8c??? . At such high speeds, they'd be hard to intercept. A huge laser defense system migh work for stuff incoming at 0.2c.... but 0.99c ... forget about it.

As I see it, space war would likely be flinging missiles at space assets that the enemy has... and expensive laser installations to defend high value stuff (like a population center or major colony). In some cases, it may come down to a laser match.

There would probably be two doctrines: a limited war in which only space assets are targeted and planetary surfaces are generally left alone... akin to limited warfare today where nukes aren't used and population centers aren't bombed.

and... all out war.. asteroids get deflected, Kinetic energy weapons are launched, nukes/antimatter warheads get thrown, the objective is to anihilate all civilization on the planet.

In neither case does this involve a warship in orbit around a hostile planet... no space marines get sent down to fight on the surface... at least for cases of two independent technologically advanced and industrialized civilizations.

It could happen in an imperial-colonial dynamic, where the imperial side has full knowledge of what is going on in the colony, and the colony has no weapons capable of threatening low orbit. In that case, one could imagine civil unrest and the colonial government/police forces becoming unwilling to obey the imperial commands. Then the imperial side might send space-warships to low orbit (if its just interplanetary, they could do this faster than the colony could build adequate missile/laser/mass driver systems... assuming there weren't mass driver/lasers systems for civilian purposes that could be quickly repurposed for defense)... some of which would be "troop carriers" (carrying more than just troops, but armored ground vehicles, atmospheric craft etc) and oribital bombarment craft (like deploying a system of UV/visible/IR lasers for precision strikes from orbit).

They'd probably land ground forces once, in one area, rather than shuttling back and forth between orbit with "dropships" (though, on a terraformed mars for instance, its a lot easier to get to and from orbit). While this would be "limited war", they might carry a substantial amount of nukes... since nuking a few cities is nothing compared to obliterating a planet with a KEW/asteroid impact. The orbital bombardment would probably be done by deploying satellites, rather than warships. You'd probably have one transport come with an efficient drive packing many laster sats, and deploy each one... each one haveing a much lower powered propulsion system mainly for station keeping.

In conclusion:

Missiles much like we already have

Lasers for shooting down missiles, with limited but non-zero offensive potential

Mass drivers for defending low orbit (if they even bother... if nobody builds ships for attack from low orbit, no one will bother to build defenses... much like militaries don't give soldiers shields to protect from arrow vollies)

Asteroids/KEW missiles/missiles with nuclear or antimatter warheads for when you're really out to destroy the enemy

[todofwar]

8 hours ago, Bill Phil said:

LEO Kessler resolves itself within a short period of time, and higher altitude kessler, such as in GEO, can be avoided by launching on an inclined trajectory.

But would it be long enough for Mars to build up its own defence systems? Unless an alien comes in with high technology, I'm pretty sure the Earth is actually well defended. We wouldn't launch nukes at targets but those ICBMs could probably be packed with some conventional explosives and take out ships in orbit. Once any lander comes in we can treat it like an ICBM and take it out with missile defense systems. So Earth has the advantage over Mars, but Mars probably wouldn't have any such defense systems leaving them vulnerable to orbital bombardment. So, could Kessler buy them a few years to get a set of defense missiles capable of reaching orbit? And a missile defense system to take out landers forcing invaders to land far away from the main settlement?

8 hours ago, tater said:

Martian colony declares independence.

Earth stops sending them supplies.

Martians die.

The End.

 

Depends on the state of the colony. Self sufficiency isn't that hard really, though a colony that can continue to grow and develop completely independently of Earth would be a bit tougher. But there's already a long thread on colonization and the challenges there.

[Atlas2342]

42 minutes ago, todofwar said:

But would it be long enough for Mars to build up its own defence systems? Unless an alien comes in with high technology, I'm pretty sure the Earth is actually well defended. We wouldn't launch nukes at targets but those ICBMs could probably be packed with some conventional explosives and take out ships in orbit. Once any lander comes in we can treat it like an ICBM and take it out with missile defense systems. So Earth has the advantage over Mars, but Mars probably wouldn't have any such defense systems leaving them vulnerable to orbital bombardment. So, could Kessler buy them a few years to get a set of defense missiles capable of reaching orbit? And a missile defense system to take out landers forcing invaders to land far away from the main settlement?

https://en.wikipedia.org/wiki/Laser_broom

Because I really want Earth to win...

[tater]

2 hours ago, todofwar said:

Depends on the state of the colony. Self sufficiency isn't that hard really, though a colony that can continue to grow and develop completely independently of Earth would be a bit tougher. But there's already a long thread on colonization and the challenges there.

Self-sufficiency is in fact incredibly hard. As there is no plausible need for a relationship between Earth/Mars, why would Earth care what they do? If Mars somehow owed creditors on Earth, the solution is not sending anything from Earth. The "commerce" would really be a one-way affair.

[todofwar]

Ok, new scenario. We settle all the galilean moons. War breaks out between them (maybe I'm a pessimist but I don't think people ever need much of an excuse to kick off a war). Easy to orbit, not a long transit time between them. So, what does that battle look like? Let's assume they already solved the issues of colonizing the moons.

[Emperor of the Titan Squid]

I dont think that (at least in the inner planets) there will be a space war until the advent of nanotube, (both carbon and boron nitride) space elavators and fountains, and compact hight efficiency nuclear fusion. When thatey do, objectives will be to capture the moon(helium 3), and destroy the elevators.

[tater]

A scenario isn't enough. You need all the givens. What drives do they use? What are the goals of fighting, exactly (it's a bizarre idea frankly that they would have much to fight about)? 

[Bill Phil]

3 hours ago, todofwar said:

Ok, new scenario. We settle all the galilean moons. War breaks out between them (maybe I'm a pessimist but I don't think people ever need much of an excuse to kick off a war). Easy to orbit, not a long transit time between them. So, what does that battle look like? Let's assume they already solved the issues of colonizing the moons.

Why massively settle such low gravity world's? You'll need centrifugal cities to prevent major atrophying...

[Atlas2342]

That depends...how advanced are their weapons?

[max_creative]

On a relatively low gravity world, have IPBM's (interplanetary ballistic missiles) and shoot the enemies. Or redirect an asteroid at them. 

How ever it turns out, it won't be like Star Wars.

[KAL 9000]

17 hours ago, max_creative said:

On a relatively low gravity world, have IPBM's (interplanetary ballistic missiles) and shoot the enemies. Or redirect an asteroid at them. 

How ever it turns out, it won't be like Star Wars.

Dang. I like Star Wars.

[max_creative]

Just now, KAL 9000 said:

Dang. I like Star Wars.

Me too.

[radonek]

On Saturday April 16, 2016 at 11:53 PM, daniel l. said:

Instead it will be ships detecting each other on LIDAR and jumping in point blank to ensure that no shot misses, Like this.

Pretty cool huh?

Pretty silly. Sorry. Distance in space combat is mostly function of light lag. If you can use active stuff like LIDAR, you are at point blank range already. Jumping to visual vicinity gives about as much sense as  two naval carriers trying to hook and board each other.

On Sunday April 17, 2016 at 8:48 PM, Bill Phil said:

Why massively settle such low gravity world's? You'll need centrifugal cities to prevent major atrophying...

Because its way easier problem to solve then "how to get stuff from bottom of deep gravity well without incredibly expensive rocket boosters". 
 

[magnemoe]

An war in space will depend on technology level. 
The only way you can get an high scale space war would be 1) faction on Earth see deep space as no man land, think america during the age of exploration. Read an book Stone Dogs who had an good handle on this.
2) you teraform an planet or create an asteroid civilization who you then end up in war with. 
Aliens would be apes or angels so no fight. 
An space war today would be ratter boring, some asats more suborbital impactors, if the war drag out more ground based energy weapons. 
Real warships would require fights over Mars Ceres or Jupiter. See 1 or 2

[magnemoe]

Self-sufficiency is in fact incredibly hard. As there is no plausible need for a relationship between Earth/Mars, why would Earth care what they do? If Mars somehow owed creditors on Earth, the solution is not sending anything from Earth. The "commerce" would really be a one-way affair.

Yes about Mars, now go to the asteroids, they can make stock food, everything else come from Earth, other food like meat from earth, lots of advanced products who is only economical to produce for an billion customers also come from Earth. A few advanced materials and most raw materials come from the belt. 
An conflict will start as an boycott on both sides, followed by blockade. 
Both sides are rational and they know both sides will be present after the conflict, belt allow exploration and tourist ships from deep space to pass back to Earth, Earth allow shipments of important medicine to go to belt. 

Earth see this as an long term issue, compare strategic oil supply so they arm and build an group of ships to go to Jupiter trojans including an skvadron of  orion battleships.
No this will not help the current situation but will change future balance, Belt can either confront them directly, might win but will loose a lot of their capital ships and increase the conflict or follow and try to make problems.