Data File Uploaded: Wednesday, February 5, 2003

Bases and defense satellites and ground-based defense installations all exist and are used in Outsider, but generally only around planets and planetoids.  

The drawback of massive fixed defenses in space is that they're easy to attack from extreme range. If you can't maneuver, anyone with a chalkboard and some basic math skills can figure out exactly where you're going to be at a given moment, and arrange for something unpleasant to meet you there. Kinetic energy is 1/2*m*v^2, so a 227 kg mass moving at 50% lightspeed has a kinetic energy of 2.5 x 10^18 joules, or two and a half billion gigajoules. In comparison, the energy output of a 1 megaton thermonuclear device is 4.2 million gigajoules. That's an extreme example, but even a payload going at 10% C (which is a more reasonable top velocity for a ship in Outsider) is going to be hard to intercept. It's small and ballistic, so it's very hard to detect (except with active sensors), and to prevent impact you have to deflect each projectile (vaporizing them doesn't do much good; mass is mass, and 227 kg of vapor at 10% C will still kill your installation just as dead).

The other drawback to massive fixed defenses is that your enemy has to be obliging enough to attack them. As Guderian or Schwartzkopf would tell you, it's much easier to go around.

Ground combat is conducted with the same classes of weaponry we're accustomed to (infantry, armor, artillery, air), and won't be explored much in the story.  

The problem with trying to defend a jump zone is that planets, bases, minefields etc. orbit the system primary; jump zones are fixed. If you place mines or a stationary base (or any object) in the jump zone, unless it is constantly applying thrust, it will fall in toward the primary; if you place it in orbit, it's orbit will carry it away from the jump zone radially. A lot of SF has "perimeter defense" stations set up on Pluto; but since Pluto orbits 360 degrees around the sun, it would be out of position of any given jump zone about 80% on the time. And that's assuming that the jump zones are in the planetary plane, which most won't be. So, if you want to mine a jump zone, your mines have to be spacecraft that are periodically refueled (expensive), and if you want a "base" there, the base has to be a System Defense Boat that can maneuver on its own. Certainly at the very least you will want to keep some sort of pickets in the area to monitor the zone; this can take the form of patrol ships, manned or otherwise. However, unless you have a substantial force stationed at the jump zone, you'd better be prepared to lose whatever pickets you post there if a major enemy force appears.

But, in any case, it is the clash of the fleets that is going to determine the outcome of a system battle; fixed defenses may give one fleet an advantage in this decisive battle, but they will not by themselves determine the outcome. Any determined fleet assault can overcome a fixed defense, no matter how extensive (battle stations, ground bases and defsats can't dodge; they will eventually be hit), unless the assault is opposed by another fleet. The question then becomes: where does the defender choose to make his stand?

If you choose to defend the planet, you will have the advantage of the planet's fixed defenses being at your back. You will also have time to assess the enemy's strength and force disposition (as you watch him assemble at the jump point). This will give you the option to retreat with your fleet intact if you feel the situation is untenable. Duty may be easier for the ships and crews, as they are closer to resupply and planetary leave. The disadvantages are that the enemy will have time to marshal his forces in an orderly fashion, and choose the best method of attack. If you have more than one location in the system that requires defense, you may have to split your forces or choose which to defend.

If you choose to defend the jump zone, you will have the advantage of being able to oppose enemy entry into the system immediately, when the enemy may be disorganized or not yet fully assembled. The disadvantages would be that you are committed to battle; if the enemy comes through with a larger force than you expect, you risk being overwhelmed without the option to retreat. Resupply will be more of an issue. And you had better be sure of where the enemy is coming from; if they arrive in a different jump zone from a different star system than the one you're defending, you'll be out of position, and they may be able to attack a target before you can intercept them. And, such a battle may favor the side with more effective short-range weapons, since the enemy may arrive right in your lap.

You can split your forces, of course, but since the outcome of the battle will usually be determined by fleet action, this is generally not a good idea unless you are certain you have ships to spare, and don't mind losing a few guarding the jump point. (I think you can guess which side favors this sort of tactic.)

In some situations, there won't be a planet to defend at all; at Naam, for example, the two fleets were battling in open space. Naam is an intermediate system, without installations (red dwarf, proplyd); the Umiak were moving through on their way to attack another system; the Loroi were intercepting that fleet. In such a case, you almost certainly want to keep your forces together.

Pluto has as an orbital period of approximately 250 years. Assuming you put a forward operating base out at approximately same distance, you could probably expect an "operating life" of 20-50 years before it moves out of position of that jump zone.

Good point. you can tow a base into position, and then just tow it back into position a few years later.

In my earlier post, I had proposed that the outlying forces should be "light" types. Destroyers and fighters. This should be enough to counter any raiders, but in the face of any major force, it should fall back.

Certainly there will be police cruisers (or equivalent) patrolling major systems, that can respond to raiders and the like, but they won't be directly in the jump zones, so that they may have a chance to fall back. If you're in the zone itself, the enemy may appear directly in your lap, and the option to retreat will have expired.

Anyway, the loss of the pickets wouldn't be a major loss.

Those pickets are manned by real people. Throwing away lives like that would be a mark of desperation, or perhaps just callousness to the lives of one's crews -- neither of which is likely to do much for morale. Remember that the war has been going on for 25 years; by this point, keeping up morale is nearly as important (and difficult) as tactical positioning. I don't know about you, but if I had to sit around for months on guard duty, knowing that in all likelihood I was eventually going to die, my morale would suffer. I wouldn't even want to have to assign someone to such duty; I don't like sacrificing units, even in computer games.

Umiak commanders won't have such issues, of course.

There really isn't much advantage to having pickets in the zone, anyway. If you're not going to oppose system entry with a substantial portion of your force, it's just as well to let the enemy have free run of the zone. They're in plain sight; you can see what they're doing with your telescopes and radar from clear across the system.

Or you could throw asteroids down jump zones or something. Be creative.

Space is big and ships are small; the odds of collision are very remote. To have a chance of impeding entry, you'd have to fill the zone with so much debris, it would be a huge task, and an even bigger one to clean up later. Remember that whatever you throw into the zone, you're going to have to track down and clear out before you can use the zone yourself.

I suppose if you wanted to close off a single system altogether, it could be done... it would be a huge, ongoing task (as the debris won't stay in the zone indefinitely), but theoretically possible.

Earth/Sol is not the only Terran system, by the way... humanity comprises six worlds on four star systems (Sol(2), Alpha Centauri(2), Tau Ceti, 82 Eridani) and a number of outposts. So closing off Earth's jump zones would be leaving the colonies twisting in the wind. And the Terran Colonial Authority does have a small military fleet, consisting of six heavy cruisers and about a dozen destroyer-class vessels. These vessels aren't on the Alien Contact mission because they don't have the range of the Bennet-class scouts; moving them so far into the unknown would be a logistical nightmare, and anyhow Humanity's leaders would rather keep their only defense forces at home.

I think you're talking of pirates or other opportunists trying to take advantage of the chaos in under-armed ships.

I undestand what you mean. Commerce raiding requires that the raider force be able to bypass the enemy fleets and be able to strike at poorly defended systems or support shipping. Because of the nature of jump drive, you can generally only transit between nearby systems. Generally, your star system is either at the front or it isn't. If it is, it's got substantial defenders. If it isn't, it has almost no defenders, since the enemy can't reach it directly. It's hard for a small raider force to get deep into undefended enemy territory, since it must first crash through the "front" tier of systems, which are heavily defended.