What would a realistic spaceship chase look like?

SF: discuss futuristic sci-fi series, ideas, and crossovers.

Moderator: NecronLord

User avatar
Formless
Sith Marauder
Posts: 4139
Joined: 2008-11-10 08:59pm
Location: the beginning and end of the Present

Re: What would a realistic spaceship chase look like?

Post by Formless »

I can think of a few reasons why a battle might happen in deep space.

1. Fleet interception. Obviously if you see a fleet coming in at a certain vector, its important to shoot them down before they reach your planet or colony. This is however where its most tempting to use unmanned craft like drones, missile buses, and laser focusing elements since you already have targeting data.

2. chasing down stealth craft. I'm sure we all know by now that stealth in space is possible if you know how to cool your ship to look like a random piece of space junk or fit into the spectra of the sun (and other such tricks), but as soon as a stealth craft has finished its mission, it may need to get the hell out of dodge before it gets shot down, and that could mean ditching stealth and using faster, hotter engines. Like submarines, though, the enemy may want to chase it down and capture it intact, which gives you your chase scene.

Oh, and stealth craft are the one kind of manned vehicle that may be tempting to launch in an interception mission, as described before. The other weapons you launch might only damage the fleet, but the stealth craft can continue harassing the invasion fleet for longer because they can't easily be seen. There are even designs out there for stealth fighters and motherships, so just finding one stealth craft doesn't mean there aren't more out there. You can see how this starts to resemble the use of submarines in WWII.

3. Stealth ships encountering each other by sheer bad luck in the depths of space. Every stealth tactic I've seen still has a range limit, and underneath that limit you become detectable again. It might be that both parties to war had the same idea and thus launched their stealth craft on opposing, but identical vectors. Its unlikely, but could still happen, and would be incredibly tense. Each commander would have to decide whether its more important to achieve his own mission, or stop the other ship from achieving their goal, or alternatively, weigh the risk that the other ship is communicating with command via a laser beam message that could compromise him anyway. Shooting could compromise both missions, especially since it would be at incredibly short range (by space standards). Lots of story potential here.

4. Destruction of deep space sensor platforms. I know the objection to stealth in space is contingent on there being sensor platforms behind enemy lines (a feat which itself requires stealth), but that's incentive for both sides to find and shoot down these sensor platforms so that they can launch stealth ships or even entire fleets under the cover of stealth umbrellas. This way you don't have to worry about your enemy launching an interception mission that damages or destroys your invasion fleet.

5. Space stations and space colonies located at Lagrange points. Earth has at least one large Trojan asteroid which would be tempting to hollow out and colonize, and Jupiter has tons more in its Lagrange points which I think have more ice trapped in them than the main belt asteroids tend to have.

Now having said that, I feel I must address Eternal_Freedom here:
Again though, those still have "terrain" of a sort - think of it as "anything that constrains the battle area" rather than geographic features.
This is not relevant, because the "geography" everyone else is concerned with is that which you can literally hide behind so the enemy can't see or shoot you. Islands and the like. In open ocean, the dynamics of the fight are very different than on the coast or in an archipelago. The same is true in deep space. So while the gravitational topography of space means there is a "reason" for placing stations in Lagrange points, it doesn't change the fact that a battle there only has the station itself to use for cover (which may be a warcrime if its a civilian installation like an O'Neil cylinder), which is vastly less cover than a planet or moon can provide in orbital combat. Combat and chases in deep space are much more predictable than combat near planets for this reason, unless stealth technology is involved.

And I guess that's one reason I always bring up stealth technology in these discussions. Not only could it actually be real, its a very good storytelling tool for getting around the things that make space combat potentially boring. It opens up another aspect of the fight: intelligence and information management. Maybe the fight hinges on news about whether or not a certain sensor platform is still operational, or having a fleet commander risk spreading out so they can detect and locate a stealth craft via multiple solar occultation events. Now your characters have to think their way to victory, not just pray that they win by sheer numbers, luck and firepower.

6. Statites and quazi-orbital stations. Similar to the above, but using solar sail technology to make a spacecraft orbit more slowly than its orbital distance would usually allow (a "quazite"), or even allowing a spacecraft to stay completely stationary relative to the sun (a "statite"). Unlike stations in Lagrange points, these ships can be placed at any arbitrary point in solar orbit, justifying encounters with them anywhere in deep space you would like. However, the solar sails are likely going to be so big that everyone in the solar system can find them with trivial ease (though statites are basically invisible at interstellar distances to planet hunting telescopes. A quazite on the other hand would be a dead giveaway for intelligent life in the system, as their orbit is too slow for their orbital distance). A tempting place to put a quazite would be between the Earth and the Sun, with an orbit slowed to match Earth's orbit, thus allowing it to detect solar flare events before they can hit the Earth. Just as one example of why you might make such a thing.

That's all the reasons I can think of at the moment why enemy ships might encounter eachother in empty space, but I'm sure there are more.
"Still, I would love to see human beings, and their constituent organ systems, trivialized and commercialized to the same extent as damn iPods and other crappy consumer products. It would be absolutely horrific, yet so wonderful." — Shroom Man 777
"To Err is Human; to Arrr is Pirate." — Skallagrim
“I would suggest "Schmuckulating", which is what Futurists do and, by extension, what they are." — Commenter "Rayneau"
The Magic Eight Ball Conspiracy.
User avatar
Jub
Sith Marauder
Posts: 4396
Joined: 2012-08-06 07:58pm
Location: British Columbia, Canada

Re: What would a realistic spaceship chase look like?

Post by Jub »

A pirate base is set up around a rogue planet 250,000 from the nearest star. They send a ship into the system having bleed off almost all of its heat and speed and it approaches no close than Pluto where it catches a laser from a habitat orbiting the sun forming the start of a Dyson swarm. That laser transmits a bunch of the latest news, science updates, and the shipping routes and dates of outgoing cargo vessels to the nearest star. There's no FTL and the colonies are new enough that waiting a decade for complex electronics shipped from Earth will still make sense by the time they arrive.

The ship takes a week or so to push itself out of Pluto's orbit using cold gas thrusters and has been burning its main engines on a course for home for a few days before anybody notices. Your nearest patrol craft is docked near Saturn and won't catch the rogue vessel until it's out of the Oort cloud and in what is basically empty space. The chase will end once the pirate craft is within 100 AU of the rogue planet because the communications lasers the base uses are strong enough to kill anything fast enough to be worth sending in less than 3 seconds under the beam.

How do you write this chase?
User avatar
LadyTevar
White Mage
White Mage
Posts: 23145
Joined: 2003-02-12 10:59pm

Re: What would a realistic spaceship chase look like?

Post by LadyTevar »

Jub wrote: 2020-06-12 08:33pm
How do you write this chase?
Ask Stephen Garrett. He's published a series of novels with space chases like this
Image
Nitram, slightly high on cough syrup: Do you know you're beautiful?
Me: Nope, that's why I have you around to tell me.
Nitram: You -are- beautiful. Anyone tries to tell you otherwise kill them.

"A life is like a garden. Perfect moments can be had, but not preserved, except in memory. LLAP" -- Leonard Nimoy, last Tweet
User avatar
madd0ct0r
Sith Acolyte
Posts: 6259
Joined: 2008-03-14 07:47am

Re: What would a realistic spaceship chase look like?

Post by madd0ct0r »

LadyTevar wrote: 2020-06-15 10:45pm
Jub wrote: 2020-06-12 08:33pm
How do you write this chase?
Ask Stephen Garrett. He's published a series of novels with space chases like this
The pirate probe is almost certainly robot only, and will broadcast the data ahead of itself in a tight beam transmission to the base as soon as it gets line of site to itself or another pirate probe. The data for the shipping routes is robustly encrypted, but the pirates continued existence suggests that they have ways or means. We don't want to make their life easy, but this is a situation of a modest response, ideally one that depletes them.
Capturing the probe intact might give us useful info, and I'd be prepared to spend a drone to try and unplug the self destruct I assume it has.

Based on their burn so far, are they straight lining back to base? If no, then my first action is to fire off a pair of missiles designed to burn to the most likely inception point and loiter. With their shortest escape route cut off, That leaves me time to try and run the probe down, assuming I have better endurance than it.

If they are straight lining then I think I will be unable to speed up enough to catch it and then change course enough to not crash through the laser zone.

So instead i want to send a hefty endurance missile up their tail pipe, something an order of magnitude lighter and more responsive then they are once it gets close (using up fuel on route). The pirate station won't be able to laser it without shooting their probe. If the probe jinks, mine follows. The pirates won't know what warhead, so they will have to spend energy destroying their own probe.
"Aid, trade, green technology and peace." - Hans Rosling.
"Welcome to SDN, where we can't see the forest because walking into trees repeatedly feels good, bro." - Mr Coffee
TommyJ
Redshirt
Posts: 15
Joined: 2020-12-07 06:49am

Re: What would a realistic spaceship chase look like?

Post by TommyJ »

If we talk about the chase itself, then it will be pretty boring. But if we talk, for example, about ways to shoot it in a movie or write about it, then there are techniques to make it super dynamic. In general, most of the chases are very boring. Even automobiles. It's just that in our time there is a movie that makes everything dynamic and interesting so that we would like to go to the cinema again
User avatar
LadyTevar
White Mage
White Mage
Posts: 23145
Joined: 2003-02-12 10:59pm

Re: What would a realistic spaceship chase look like?

Post by LadyTevar »

Mandalorian had several Space Chases that were very intense, including the opening of the Season Ender.

Now, that is at "knife range" in Space terms, more of a dogfight than anything else, since all of the battles we see in Mando are small ships, not Capitol Ships.
Image
Nitram, slightly high on cough syrup: Do you know you're beautiful?
Me: Nope, that's why I have you around to tell me.
Nitram: You -are- beautiful. Anyone tries to tell you otherwise kill them.

"A life is like a garden. Perfect moments can be had, but not preserved, except in memory. LLAP" -- Leonard Nimoy, last Tweet
TommyJ
Redshirt
Posts: 15
Joined: 2020-12-07 06:49am

Re: What would a realistic spaceship chase look like?

Post by TommyJ »

LadyTevar wrote: 2020-12-19 12:23am Mandalorian had several Space Chases that were very intense, including the opening of the Season Ender.

Now, that is at "knife range" in Space terms, more of a dogfight than anything else, since all of the battles we see in Mando are small ships, not Capitol Ships.
Yep, that's what I'm talking about. You can see dynamic chases only in movies. If you'll shot real chase it would be boring mathematics. Maybe not so boring for some people... Much of the progress in many areas is also purely calculating. Thanks to which we can observe fantastic things. But like real chases - developing this will be very boring for most people. So it still will be boring for all others.
Post Reply