Planetary Shields

[Bren]

This is a somewhat longish post, summarizing the facts about large shields and then providing my conclusions based on the facts as well as how we use large size shields in our campaign.

FACTS
In ESB General Veers says “Com Scan has detected an energy field protecting an area of the sixth planet of the Hoth System. The field is strong enough to deflect any bombardment.

(1) This tells us that the shield does not cover the entire planet.

(2) This tells us the field is strong enough to deflect any bombardment from the Imperial fleet that is currently in the system.

The qualification in (2) is a logical inference that what Veers actually means is any bombardment that the fleet currently in the system can undertake. If it meant literally no conceivable bombardment we would have to wonder at the rationale behind the Empire building a second Death Star if it couldn’t even effectively bombard a shield of this strength.

There also doesn’t seem to be any reason to doubt General Veers means what he says and is not using some odd technical jargon where “strong enough to deflect any bombardment” is a another way of saying “is kind of protective, but we can bombard it and bring down the shield if we want to.” If he meant that he should have said, “The field is strong, but we can bring it down with a sustained bombardment.” I think there is no reason to assume that officers reporting to Lord Vader are going to claim that they can’t do something that (a) they can actually do and (b) that the Dark Lord of the Sith might want them to do. Officers that make those sorts of false claims are likely to get replaced by their subordinates pretty quickly.

In the extended Universe we see that,

(3) Some planets e.g. Coruscant have planetary shields (see X-Wing series of books).

(4) Some planets have been successfully bombarded by the Imperial Fleet (several sources e.g. http://starwars.wikia.com/wiki/Base_Delta_Zero and The Planet’s Collection: Elrood Sector city of Paran on Derilyn).

(5) In addition, planet descriptions sometimes e.g. Coruscant mention the presence of planetary shields and often do not mention the presence of a shield, which tends to support the notion that not all planets have planetary shields.

Therefore we can conclude one of two things (and both may be true).

Either (A) the planets that were successfully bombarded did not have planetary shields, and hence not all planets have planetary shields.

Or (B) some planetary shields are not strong enough to stop orbital bombardment. In this case given (2) above, that would mean the Hoth shield covers a smaller areas but is stronger than a planetary shield.

I suspect both A and B are correct.

CONCLUSIONS
Really I don’t think there is enough information from primary sources to determine definitive answers, but some reasonable answers can be arrived at. I’ve given this a bit of thought, in part because the availability of shields (planetary or city-sized) is a major plot point in our Star Wars campaign. Here is what makes sense to me.

City-size shields and shields like those on Hoth require enormous amounts of power requiring huge power plants. Typically these are only available to highly civilized, high tech planets with large populations to support and fund the infrastructure required.

Planetary shields are a collection of smaller shields all coordinated to work in harmony sharing and shedding power loading and so forth. A planetary shield is not a single shield, but a complicated and coordinated shielding system. This type of system is phenomenally expensive and typically only the most highly developed planets can afford such a system. In addition, I would imagine that such a system will alter the planets weather and thus without sophisticated weather control systems like that on Coruscant, operating a planetary shield system will play havoc with the planet’s weather. Think massive lighting storms, sudden tornadoes, etc. The requirements of huge power sources, complicated coordination, and existing weather control are why we don’t see planetary shields on the vast majority of Star Wars planets.

Just like shields on starships, I presume city-size shields and planetary shield systems can come in various power levels. Lower level shields would be sufficient to deter pirates and raiders from damaging a city or planet. Moderate level shields would be sufficient to deter say a single Star Destroyer. Higher level shields like those on Hoth would be sufficient to deter a fleet like that seen in ESB, but could be brought down by a torpedo sphere given skill and time. Really high level shields like the double shields on Coruscant (and possibly only the shields on Coruscant) are sufficient to hold off huge fleets and multiple torpedo spheres. A Death Star is sufficient to take out all known shields. Although perhaps Coruscant’s shields should be an exception, depending on what fail-safes Palpatine had put in place to prevent the Death Star being used to blow up his planet of residence.

The cost and power requirement of a shield scale exponentially with both shield strength and shield coverage. Thus planetary shields should require many thousands (millions) of times the power and cost of a smaller Hoth-size shield. I think the WEG rules on large shields makes the shields too inexpensive on both accounts. In addition, the Empire would restrict large scale shield technology in the same way that nuclear weapons technology is restricted on earth today.

IN MY CAMPAIGN
Only on those planets that the Emperor wants shielded will this technology be legally and readily available. Some planets will have planetary shield technology predating the Empire’s restrictions, but these will tend to be older and less efficient systems.

The Empire will use city-sized and base shields to protect various sensitive installations. Since the Rebels, at this time, don’t have a massive fleet, these are probably only of medium power. In addition, the Empire will allow such shields to legally be acquired (for pro-Imperial governments) to protect capital cities and such. Typically they won’t allow full planetary shield systems to be acquired or installed. Consequently city-size and base shields will be somewhat available (through theft or diversion from legitimate channels) on the black market.

Consequences:
Very few planets have full planetary shield systems. But some do. Many more capital cities (of major, high-tech planets) will have city-size shield protection. Therefore the Empire can threaten most planets, even if the capital is protected. Obviously the Death Star would allow the Empire to threaten all planets (with the possible exception of Coruscant).

Many Imperial bases and some cities will have shields. Therefore Rebels may need to sneak into such areas. In game, this makes for interesting complications.

Some Rebel bases and pro-Rebel cities may have shields. This allows the possibility for many Hoth-style battles where the Rebels need to hold off ground forces while they try to evacuate.

Rebel bases and some pro-Rebel cities will need to acquire their shields on the black market or by stealing them from the Empire. Presto – a perfect scenario idea for the ever resourceful PCs.

Disclaimer 1: I can’t explain how the Rebels were able to move and install the power plant necessary on remote Hoth, but it must have required a lot of engineering work, core taps for power, etc. (The real answer, I suspect, is the shield was powered with plot power and George just wanted to have a cool (Hoth, rule of cool, get it?) battle in the snow with AT-ATs and snowspeeders. The shield was the excuse for why the Imperials couldn’t just land right on top of the Rebel base or blow it to oblivion.

Disclaimer 2: I can’t explain the failure to protect the thermo exhaust port on the first Death Star. Has anyone heard of armored baffles? Anyone…anyone…Bueller? But it is possible that shields trap some energy inside as well as reflecting it from the outside. Perhaps that prevented use of such a shield on the Death Star. Though I suspect that would cause Coruscant to cook in its own reflective heat. I think I prefer the (hand waving answer) that large shields need to use the planet’s magnetic field to power/enhance the shield.

[ZzaphodD]

[atgxtg]

According to Wookieepedia there are a couple of otyher details that would help/apply here.

1- The power generator on Hoth is drawing geothermal energy. If so, it would explain why such generators couldn7t be installed on a ship. Basically, it is tapping into the huge natural power reserves of the planet.

2-THe terms powerr generator and shield generator are used interchangelby in thre wiki. I'll have to check ESB to see if that was done during the film. Does Veers destroy the shield generator or the power generator? This is of mostly academic interest, but would help to determine the size of the generator.



I still can7t see why the Emperiee couldn't fly bombers down under the shield and then bombard the base, but then I could never understand why the Rebels both with the ineffectual T-47 snowspeeaders when they could have trashed the AT-Ats with starfighters.

[ZzaphodD]

[Esoomian]

[atgxtg]

[Yasriia]

[Bren]

[atgxtg]

Maybe the Praetor-class Star Battle Crusiser is some sort of assault ship? Then a umbrella shield that was directed towards the planet the Pretor was bombarding would make sense.

[Bren]

[atgxtg]

It7s also kinda interesting that the old Roman title of Praetor is used for the ship class name. I think that is the only Roman-specfic term I7ve seen in Star Wars (yeah, they have legion, but that is much more generic). AFAIK the title of Moff is farily close to to that of a Preator, too, that is some type of military field commander or provvincal governeor

Wildly speculating, I wonder if the class name had something to do with the duties of the ship. Maybe it was some sort of command ship.That would explain why, if the shield came from such a ship too, it would be able to deflect a strong bombardment. It would make sense to try to protect the field commander and maintain command and control.

Perhaps the Praetor-class was some typre of field HQ dropship?The the umbrella shield would be just the thing to protect the field HQ

[Gregorius]

"In ESB the fleet could not (or would not) bombard the rebel base."

I think I have a plausible reason for this.
It is stated in ESB's opening crawl that Vader is obsessed with finding Luke. Therefore, orbitally bombarding the base would not help Vader acheive this, and yes, I do agree with Bren that Veers was stating truth when he said hat it could deflect any bombardment that they had at their disposal.

I also believe that the shield might have had some form of Electro-magnetic shielding to protect against Ion bolts. It is somewhat illogical to believe that no way has been found to counter Ion cannons, when it is public knowledge that they exist. I believe that somke form of EM shielding on these kinds of highly powerful shields (remember that it is off a Praetor-class, supposedly a command ship, therefore warranting much more protection than a normal warship) would have some form of EM shielding.

[Tem_Starrunner]

The idea that Vader wanted prisoners seems plausible but I don't think that was the reason for just a ground assault.

Planetary shields disrupt sensors so it makes them difficult to near impossible to detect anything through them.

The reason I think Veers says the shield can take any bombard is because of the coordinating necessary to take them down. A Torpedo Sphere alone takes days to scan and calculate the proper location to bombard and then use (I'm assuming here) a salvo from nearly all of the 500 torpedo launchers and then taking out the shield generator with its turbolasers. The target zone is only six meters across.If they get anything wrong they have to start from the beginning.

The entire Death Squadron could fire their entire weapons complement but they would have to do 3 things.
1: Coordinate all guns to fire at once.
2: Concentrate all weapons on a six meter location
3: Hit the shield or power generator
There's to great a chance to hit something that they didn't mean to because their firing blindly at the target. If they don't hit the shield or power generator then the shield stays ups.

Now the reason that ion cannons don't work is the same problem as turbolasers. Your firing blindly at a target even if the ion shot goes through the shield if doesn't hit shield or generator the shields stay up. Or its possible that ion cannons are useless against a ground target because they're grounded (unlike a starship) and simply shunt the ionizing charge into the ground like lightening.

[garhkal]

I like the idea on Ions getting groundedout.
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[Esoomian]

But then why can you ionize a droid in the way that the Jawas ionized R2D2?
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