Planetary Invasion/Defense

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Mikk
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Re: Planetary Invasion/Defense

Post by Mikk »

If a bombarding fleet had to conserve fuel, there's no reason they couldn't spread out along their orbit (or different orbits) to have continuous coverage of a point on a planet without having to climb to synchronous orbit if such exists. That's one benefit having more than one bombard capable ship has. Even if your whole fleet (or single bombard ship) can't keep firing at all times, observation craft should be pretty cheap to have around.
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Zakharra
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Re: Planetary Invasion/Defense

Post by Zakharra »

If the humans have nuclear bomb pumped X-ray lazers, those could be the mines. A lot depends if the Logirei can achieve orbit. If they are intradicted, their options are limited for awhile. If there are no mines, then they will have orbital supremecy and it's a moot point.

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Mjolnir
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Re: Planetary Invasion/Defense

Post by Mjolnir »

Another thing about orbital bombardment...even if it sends the target scurrying for cover, it restricts the targets to staying near cover..."cover" in this case pretty much being something the attackers don't want to destroy. And since the target can't be determined while the projectile's still minutes out, a single projectile can force ground targets over a wide range to abandon what they're doing and try to reach safety, or remain exposed to attack. Preventing your ground forces from being destroyed doesn't do much good if they can't do anything.

It's really hard to come up with a way for large ground forces to even survive when there's a well equipped enemy in orbit. There is at least the fact that weapons for attacking planets would be relatively specialized...red-green lasers or microwave beams with large apertures and short focus and fast pulses to minimize defocusing from atmospheric refraction, and an inventory of kinetic weapons that would be rather useless against other spacecraft. Targeting systems that can see a target against a hot planetary background. Etc...

Why is this large Logieri fleet in the system? Where were they going and what were they equipped to do?

discord
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Re: Planetary Invasion/Defense

Post by discord »

as i said, one of those 'facts' must change...one possibility would be that there was a fight for the orbitals, and both fleets where seriously mauled, so the logieri troop transports are just fine but the entire escort needs a shipyard, badly....and there ain't one available right here... bingo, no orbital bombardment, at least not well aimed and specialized such, could still drop big rock, but not with precision enough to be viable in this situation.

osmium
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Re: Planetary Invasion/Defense

Post by osmium »

I'm not really sure you'd need very specialized sensors. You'd just need a different optic rather than special sensors. I think all you'd need is a different set of hardware/software pattern matching routines that are used to pick out targets (not convinced you'd need new sensors to deal with the background being much closer to the target in temperature). Compare the special optics to the price of a battleship and the fact that having a targeting computer for orbital bombardment would basically only need to be designed once and would effectively be free to put in your whole fleet and I'd bet they have the capability. As for weapondry, yeah they'll likely have to jury rig something, or just be okay melting a tank and a 20 ft diameter X few feet deep of earth at the same time.

-O

discord
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Re: Planetary Invasion/Defense

Post by discord »

osmium: aye, sensors and such, and SEE, no problem, any fleet with a significant ground pounder presence would have surveillance satellites in abundance, the problem would be AIMED weapons, that requires specialized hardware, hitting the right city? probably doable, hitting a tank WITHOUT hitting the rest of the city? without the right gear, not so easy.

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Mjolnir
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Re: Planetary Invasion/Defense

Post by Mjolnir »

osmium wrote:I'm not really sure you'd need very specialized sensors. You'd just need a different optic rather than special sensors. I think all you'd need is a different set of hardware/software pattern matching routines that are used to pick out targets (not convinced you'd need new sensors to deal with the background being much closer to the target in temperature). Compare the special optics to the price of a battleship and the fact that having a targeting computer for orbital bombardment would basically only need to be designed once and would effectively be free to put in your whole fleet and I'd bet they have the capability. As for weapondry, yeah they'll likely have to jury rig something, or just be okay melting a tank and a 20 ft diameter X few feet deep of earth at the same time.
Detecting/targeting spacecraft and ground targets have very different requirements. A sensor that can pick up a spacecraft's thermal signature might well be entirely blind pointed at a planet...remember the failure of the WIRE telescope that preceded WISE: a lens cap prematurely ejected while it was still pointed at Earth, and it boiled all its cryogen off and spun up to 60 rpm shortly after reaching orbit. In this case, being equipment mounted on a warship, pointing such sensors at a planet will probably just engage protection mechanisms. Optics aren't the issue, dynamic range and ability to handle the high intensity background are.

The sensors would indeed be cheap compared to the cost of the spacecraft, and other sensors would still be of some use, but there's still issues like time for design, system integration, and training personnel for use. It seems plausible that ships not otherwise specialized for operations against planets would have difficulty with the task. For a large fleet to have no ships with such capabilities, though...

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Martenzo
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Re: Planetary Invasion/Defense

Post by Martenzo »

Just so you know, your discussion has given me enough ideas for now. And besides, it's gone off-topic as far as I'm concerned. Feel free to continue your discussion, but know that I am no longer looking for an answer to my original problems.

osmium
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Re: Planetary Invasion/Defense

Post by osmium »

Just to note it's common for threads to be derailed into technical hard sci fi sorts of areas.
-O

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