Planetary shield distribution - cells or bubbles

[Darth Tanner]

Are planetary based shield systems cell based networks or bubbles sustained by multiple generator locations.

We know that the shield on endor was generating a field not only around the entire second death star but also around endor itself. Both cases show that the single dish shield generator was capable of putting a shield around things it had no direct line of sight to but also that the shield being generated was a single bubble, not requiring multiple generators to maintain different cells of the shield and indeed that a single dish was putting up two shields simultaneously.

Additionally the planetary shield on Alderaan is clearly seen to fail as a single bubble, with the death stars energy being absorbed by a large section of the bubble, not simply punching through a single cell.



However other planetary shields in the EU, noticeably Coruscant and Bothawui utilise shield networks with large number of generators maintaining shield cells above them independently from other generators. When a single generator on Bothawui is sabotaged it leaves a gap that pretty much defeats the entire shield system with a single star destroyer being expected to be able to exploit that hole to lay waste to the entire planet, likely by angling its fire to hit other shield generators through the hole or simply causing such devastation with its bombardment of the unshielded section of the planet that the seismicand blast effects disable the surrounding shield generators.

If as shown on Endor shield cells can be moved about, generated away from the emitters line of sight or indeed do not exist with a single shield bubble being generated why could the surviving shield generators not extend their cells to cover the gap.

It seems a rather large design flaw in a shield system to localise generator capacity when you don’t need to as an attacking fleet can simply concentrate fire on one section and bring it down with massively less firepower required than would be to bring the entire shield system down.

So which is it?

Is the EU just making its own crap up to help create an exciting story? (Zahn in this case) Or have I misinterpreted the films/books.

A thought that I had...
The death star shield on endor works on a totally different mechanism from the others and is not in fact a shield capable of surviving sustained bombardment but is merely designed to prevent the fight attack on the death star. The Imperial fleet turns up in time to prevent the rebel heavy ships from bombarding it and as such removes the need for it to be of a power level comparable to conventional planetary shields.

This however does not explain Alderaan or why the rebels didn’t find it suspicious that the death star shield was not designed to stop their assault.

[Batman]

Are planetary based shield systems cell based networks or bubbles sustained by multiple generator locations.

Yes.

Additionally the planetary shield on Alderaan is clearly seen to fail as a single bubble, with the death stars energy being absorbed by a large section of the bubble, not simply punching through a single cell.

Non-sequitur. The dispersal of the beam over large areas of the shield is not incompatible with a cellular shield. Consequently there's no reason to assume a single cell would fail any easier than an arbitrary location of the shield.

However other planetary shields in the EU, noticeably Coruscant and Bothawui utilise shield networks with large number of generators maintaining shield cells above them independently from other generators. When a single generator on Bothawui is sabotaged it leaves a gap that pretty much defeats the entire shield system with a single star destroyer being expected to be able to exploit that hole to lay waste to the entire planet,

I'd very much to see the quote about the ISD being able to lay waste to the entire planet through that gap if you please. Because the plan was to cause enough damage to trigger a civil war and IIRC they expected to achieve that by simply laying waste to the city beneath the gap.

If as shown on Endor shield cells can be moved about, generated away from the emitters line of sight or indeed do not exist with a single shield bubble being generated why could the surviving shield generators not extend their cells to cover the gap.

Who says they couldn't? Why does that mean they have to be able to do so immediately when they had no advance warning the generator would fail?

It seems a rather large design flaw in a shield system to localise generator capacity when you don’t need to as an attacking fleet can simply concentrate fire on one section and bring it down with massively less firepower required than would be to bring the entire shield system down.

Which is complete contention on your part. Show that it easier to blow through a single cell of a cellular shield with significantly less firepower than you need to pierce a single-bubble planetary shield.

So which is it?

Both?

Is the EU just making its own crap up to help create an exciting story? (Zahn in this case) Or have I misinterpreted the films/books.

You're blithely ASSUMING a cellular shield will be far easier to pierce on the local level than a single-bubble shield without any evidence for that whatsoever, especially as the very capital world of the GE had a cellular shield and didn't seem particularly worried about it.
A thought that I had...

[Illuminatus Primus]

I don't know if Coruscant had a true "section-by-section" shield. I think observed cases of "bubble" shields still permit small gaps to be selectively opened. I imagine that planetary shields run a whole gamut of types and configurations based on preference, cost, etc.

[Darth Yoshi]

I'd very much to see the quote about the ISD being able to lay waste to the entire planet through that gap if you please. Because the plan was to cause enough damage to trigger a civil war and IIRC they expected to achieve that by simply laying waste to the city beneath the gap.

The plan was to start a civil war buy wiping out the two fleets and letting both factions think the other started shooting, which means that there can't be any witnesses to pin the blame on the Remnant. And there was nothing saying that the fleet couldn't launch fighter strikes to bring other sections of the shield.

[Noble Ire]

I don't know if Coruscant had a true "section-by-section" shield. I think observed cases of "bubble" shields still permit small gaps to be selectively opened. I imagine that planetary shields run a whole gamut of types and configurations based on preference, cost, etc.

Descriptions in Labyrinth of Evil and the ROTS novelization, as well as Star By Star, indicate the Coruscant sported at least two tiers of shielding, incorporating both of the noted varieties. The first and heaviest was a "bubble" screen at the upper-atmospheric level, possibly consisting of multiple layers. The secondary defensive network was a system of theater shield-esque generators that covered individual districts of the planetary city, although its unclear how extensive the coverage was.

[Batman]

I don't know if Coruscant had a true "section-by-section" shield. I think observed cases of "bubble" shields still permit small gaps to be selectively opened. I imagine that planetary shields run a whole gamut of types and configurations based on preference, cost, etc.

Descriptions in Labyrinth of Evil and the ROTS novelization, as well as Star By Star, indicate the Coruscant sported at least two tiers of shielding, incorporating both of the noted varieties. The first and heaviest was a "bubble" screen at the upper-atmospheric level, possibly consisting of multiple layers. The secondary defensive network was a system of theater shield-esque generators that covered individual districts of the planetary city, although its unclear how extensive the coverage was.

The Rogue Squadron novels explicitly mention a two-layered honeycomb shield system covering the entire planet and IIRC TLC had a segmented shield too, neither of which necessarily contradicts the above information given that was at varying points in time.

[The Original Nex]

IIRC Labyrinth of Evil also mentions individual buildings with shield generators as well as other levels. Makes sense considering the sudden raising of district shields would wreck havoc on the skylanes, and provides the city with some protection until the traffic can be grounded/rerouted so district shields can be raised.

[Coalition]

We know that the shield on endor was generating a field not only around the entire second death star but also around endor itself. Both cases show that the single dish shield generator was capable of putting a shield around things it had no direct line of sight to but also that the shield being generated was a single bubble, not requiring multiple generators to maintain different cells of the shield and indeed that a single dish was putting up two shields simultaneously.

Additionally the planetary shield on Alderaan is clearly seen to fail as a single bubble, with the death stars energy being absorbed by a large section of the bubble, not simply punching through a single cell.

Alderaan could be either. A single bubble would work by being a surface, while a cell system could have just had all the cells possible diverted towards the great big battlestation, and coordinated to let as little as possible leak through.

The other fun part is that by being designed as discrete structures, cells might be easier to maneuver against an opponent than bubble types. So you use your bubble types for full coverage, and cells to cover the gaps that appear.

Bubbles might have an easier time vs heavy impacts, as the impact is spread through the network, while cells have to deal with all of it or fail (of course there will hopefully be cells underneath each other for when they fail). There will be limits as to how much can be spread through the network and how fast, allowing for good storytelling.

If as shown on Endor shield cells can be moved about, generated away from the emitters line of sight or indeed do not exist with a single shield bubble being generated why could the surviving shield generators not extend their cells to cover the gap.

Do we know how much time there was to reorient the cells, or the time required to reorient them? If it takes 3 seconds to move a cell, and the gun can fire one shot every 2 seconds, that generator is gone.

[Darth Tanner]

I'd very much to see the quote about the ISD being able to lay waste to the entire planet through that gap if you please

As has been said the point of the operation was to leave no witnesses to the start of the civil war, thus letting it spread to the entire Republic. If the majoirty of the planets population survive to witness the star destroyers decloak then that part of the plan fails. Although I hadn't thought about the possibility of sending bombers down through the shield gap. Perhaps this is the actual use for bombers that they have been lacking in space combat.

Why does that mean they have to be able to do so immediately when they had no advance warning the generator would fail?

They don't have to be able to do so immediately, but if the shield is going to be down long enough to send fighters down to take down the other shield generators then its unlikely they can do it at all, or at least within a practical length of time.

Show that it easier to blow through a single cell of a cellular shield with significantly less firepower than you need to pierce a single-bubble planetary shield.

Because if the entire fleet can concentrate its firepower on a single cell then only a single generator is dealing with that firepower, the rest of the shield network is at that point redundant. If all the shield generators work together to produce a bubble then all of the shield generators are dealing with the firepower of the attacking fleet, minus whatever inneficiency there is in the absorbtion of energy across the bubble.

cells might be easier to maneuver against an opponent than bubble types. So you use your bubble types for full coverage, and cells to cover the gaps that appear.

This would seem to support Han with his angle the deflectors remarks. Deflection is clearly far more efficient a defence than absorbtion.

[Illuminatus Primus]

Because if the entire fleet can concentrate its firepower on a single cell then only a single generator is dealing with that firepower, the rest of the shield network is at that point redundant. If all the shield generators work together to produce a bubble then all of the shield generators are dealing with the firepower of the attacking fleet, minus whatever inneficiency there is in the absorbtion of energy across the bubble.

You're assuming that if the shield projecting hardware is not networked (individual shield segments projects and positioned at will independently), and that requires that the heat sinks and radiators cannot be. That is not necessarily true. This "magic shield power" interpretation to me makes less sense than just modeling the shielded object holistically according to thermodynamics.

This would seem to support Han with his angle the deflectors remarks. Deflection is clearly far more efficient a defence than absorbtion.

Geometry relates to the intensity of the impact; that does not require that deflection is the primary means by which energy is removed. Very few examples show a majority of the energy of turbolaser strikes being directly deflected away by the shield. Partial deflection/disruption and absorption is by far the norm. Mirrors absorb light and reradiate it; it does not just bounce.

[Darth Tanner]

You're assuming that if the shield projecting hardware is not networked (individual shield segments projects and positioned at will independently), and that requires that the heat sinks and radiators cannot be

True, and in fact from a certain angle it makes more sense to try to transfer energy once its on the ground across your network of shield generator heat sinks than to transfer it though the shield itself. Indeed some of the energy absorbed could be utilised, perhaps to operate planetary batteries or just civil power requirements.

Very few examples show a majority of the energy of turbolaser strikes being directly deflected away by the

I would have thought the blinding flashes when star destroyer turbolaser blasts hits the blockade runners shields would be just such deflection of energy. Obviously its practicaly impossible to judge how much energy is being deflected, especially if you believe that the damaging part of the blast is invisible but it likely is no where near the astronomical levels of energy a star destroyers weaponry can pump out. However some deflection is better than no deflection.

[Connor MacLeod]

leafing through the ICSes and whatnot, generators and the heatsinks do seem to be separated to at least some degree. This would make sense from a standpoint that it prevents battle damage from taking out the heat sinks/radiators all in one hit. And, like IP said, they're probably networked. In fact, some ships seem to have separate radiators for other components (engines and reactors) as well as backup radiators (Palpy's shuttle has minor and major radiators of both thermal and neutrino type) that are probably tied in for emergency/redundancy purposes.

Another reason to keep the radiators/heatsinks decentralized could be to do with surface area. While neutrino radiators eliminate many of the problems of a thermal radiator, it does seem that surface area does matter somewhat.

In any event heatsinks and radiators won't have much to do with shield segments - thats a result of individual generators and their accompanying projectors/relays (the generators create the field, the projectors and relays help to shape/direct/angle it over a given area.)

Edit: one EU example of networking I believ did occur to me. In Bacta War, the Lusankya had its shields in one section taken out by capital ship warhead bombardment - the shield operator redistributed shields from the other segments/facings to cover the gap (although this weakened protection in other areas as well.) That points to the shield generators being "linked/networked" in some fashion that they can cover one another.

[Illuminatus Primus]

True, and in fact from a certain angle it makes more sense to try to transfer energy once its on the ground across your network of shield generator heat sinks than to transfer it though the shield itself. Indeed some of the energy absorbed could be utilised, perhaps to operate planetary batteries or just civil power requirements.

Heat generally does not work like that. You can't just bottle it and move it around; entropy must increase. Ordered work will decrease in the system.

I would have thought the blinding flashes when star destroyer turbolaser blasts hits the blockade runners shields would be just such deflection of energy. Obviously its practicaly impossible to judge how much energy is being deflected, especially if you believe that the damaging part of the blast is invisible but it likely is no where near the astronomical levels of energy a star destroyers weaponry can pump out. However some deflection is better than no deflection.

Occam's razor dictates that we should not assume invisible undetectable energy emissions unless posited by other evidence. Since the visible emissions are inconsistent typically with gigaton-level events, we must admit that parsimonically, it is unlikely a large fraction of the energy is deflected.