Asteroids and Star Destroyers (NOT turbolaser-related)

McC · Post by **McC** » 2004-06-04 01:35pm

I dunno if this has been brought up before, but an attempt to search the archive yielded a memory error, so I can't check.

Anyway, there's a pretty blatant example of the command tower of an ISD being blown apart after it is hit by an asteroid in the Hoth field. Given that we can probably calculate a relative velocity for this asteroid and an approximate mass based on volume as is typically calculated for turbolaser ratings, could we not figure out possible upper limits for ISD hull properties from this? Perhaps not melting/boiling points, but other physical properties, at least?

Post by **Ghost Rider** » 2004-06-04 02:55pm

McC wrote:I dunno if this has been brought up before, but an attempt to search the archive yielded a memory error, so I can't check.

Anyway, there's a pretty blatant example of the command tower of an ISD being blown apart after it is hit by an asteroid in the Hoth field. Given that we can probably calculate a relative velocity for this asteroid and an approximate mass based on volume as is typically calculated for turbolaser ratings, could we not figure out possible upper limits for ISD hull properties from this? Perhaps not melting/boiling points, but other physical properties, at least?

Only problem and I believe many went through was that honestly we have no idea of how long they were in there.

Ubiquitous · Post by **Ubiquitous** » 2004-06-04 03:04pm

Many people claim that the bridge was not destroyed, I believe. However, with the upcoming DVD release we should have a clearer view on whether the bridge remains or not after impact.

McC · Post by **McC** » 2004-06-04 03:04pm

Right, that's very true. However, would that really come into play when examining hull-related events? For shields, certainly, but for hull as well?

McC · Post by **McC** » 2004-06-04 03:05pm

ALI_G wrote:Many people claim that the bridge was not destroyed, I believe. However, with the upcoming DVD release we should have a clearer view on whether the bridge remains or not after impact.

Well, I just watched the sequence (it's what prompted my posting) and it looks pretty gone to me. I'll post some screencaps later on this evening.

Ubiquitous · Post by **Ubiquitous** » 2004-06-04 03:08pm

McC wrote:
ALI_G wrote:Many people claim that the bridge was not destroyed, I believe. However, with the upcoming DVD release we should have a clearer view on whether the bridge remains or not after impact.
Well, I just watched the sequence (it's what prompted my posting) and it looks pretty gone to me. I'll post some screencaps later on this evening.

Oh there is nothing you could show me that I haven't seen before. I believe that the writers intended for the bridge to be destroyed, but several people have pointed to the fact that no ISD model ever had its bridge destroyed as evidence to support their case.

The DVD should shed more light on this. Until that release however, you'd just be rehashing a debate that has been done ad nausium with the same results.

McC · Post by **McC** » 2004-06-04 03:15pm

Ah. Well, I don't know why a DVD will provide any better evidence than a screencap from the widescreen VHS version -- a NTSC-based video capture is a NTSC-based video capture is a NTSC-based video capture. Whether you pull it from a DVD VOB file or from a capture card plugged into your VCR is largely irrelevant. A DVD capture might scale better than a VHS capture will (due to the vagaries of video encoding), but generally speaking...

Ubiquitous · Post by **Ubiquitous** » 2004-06-04 03:20pm

Hmm. Maybe you're right. I'm talking from the point of view of someone with an average PAL VCR that is very fuzzy compared to crystal clear pictures that I can snap from DVD's.

Time will tell, eh?

McC · Post by **McC** » 2004-06-04 03:31pm

True enough.

I'll post some screencaps later anyway, just to show you the level of clarity you can still get with a VCR. I wish I had something on VHS that I also had on DVD so I could show you an actual comparison, but alas -- no such luck

Icehawk · Post by **Icehawk** » 2004-06-04 03:52pm

A 35mm film transfer straight to a digital source WILL look better than a 35mm film transfer onto a VHS tape. The VHS format does degrade original film quality.

McC · Post by **McC** » 2004-06-04 04:02pm

Yes, true. However, the digital source is limited by its actual pixel-level resolution. As I said, it may scale better, but at a one-to-one comparison, in my experience there is very little difference.

phongn · Post by **phongn** » 2004-06-04 04:29pm

The main page has an entry on this very issue.

McC · Post by **McC** » 2004-06-04 05:01pm

That discusses the implications of the impact with respect to shields -- I'm looking at it more as a strictly physical impact to get an upper limit on ISD hull resilience rather than as an exercise in shield resilience. It's an upper limit because we don't know how much of the impact energy had already been mitigated by the shields (if they were up).

phongn · Post by **phongn** » 2004-06-04 06:06pm

McC wrote:That discusses the implications of the impact with respect to shields -- I'm looking at it more as a strictly physical impact to get an upper limit on ISD hull resilience rather than as an exercise in shield resilience. It's an upper limit because we don't know how much of the impact energy had already been mitigated by the shields (if they were up).

All that momentum gets transferred to the ISD somehow (conservation of momentum).

Howedar · Post by **Howedar** » 2004-06-04 07:05pm

On that note, I'd say probably the strongest evidence for a blown-off bridge tower is that the ISD experiences no visible velocity change.

McC · Post by **McC** » 2004-06-04 10:14pm

Those are the two most-applicable frames from this particular sequence. I was originally going to point out the shape of the orange glow from Executor's engine well, but it turns out that it retains the silhouetted shape of the ISD's neck structure! It's moved forward, since all the vessels in the scene were moving, but there does appear to exist some continued obscuring feature.

However, in the first frame you can see the scanner globe beginning to obscure Executor's lateral trench, while in the next frame you can clearly see the whole line of the trench. At the very least, the top portion with the scanner globes was destroyed, and based on the lack of physical presence, I would speculate that the whole hammer-head command structure (in front of the neck join) went with it.

Another interesting point: they didn't clean up the matte line. This is from Empire SE, and you can still see the matte line of the asteroid field and the destroyers at the top of the image (the division between blackish and blueish).

Spanky The Dolphin · Post by **Spanky The Dolphin** » 2004-06-04 10:26pm

McC, this is honestly hardly a new issue. In fact, it's very old and has been covered from almost every angle by dozens of people. I seriously doubt that you're going to find anything new whatsoever that hasn't been already covered.

McC · Post by **McC** » 2004-06-04 10:43pm

I have been made aware of that, Spanky. However, the only thing I've seen is a figure in joules relating to the KE of the asteroid impact. What does this tell us, if anything, about any other properties of the ship's hull composition? What are the implications of this impact if shields are down? The most I have seen is what Mike has on his shields page, which -- appropriately -- talks about implications in terms of shields, not hull resilience.

If this has been gone over many, many times, point me to the analysis and I'll read it and be content. If there isn't one publicly available, then perhaps someone can provide one from their private records. And if those don't exist, then let's do it again. I haven't seen the data, and I would like to. If that comes across as arrogant, then I'm sorry, but hording the information if it's available isn't doing anyone any good and if it's not, then why don't we make it available? And if it's already been done, like I said, point me at it and I'll look at it and be content.

Post by **Darth Wong** » 2004-06-04 11:23pm

First, the biggest problem with the idea that the whole bridge tower was totally destroyed is simple: where did all of the material go? Did it fly to starboard and down at super-speed, so that it would disappear from view in milliseconds? And why is the ship's captain still alive and broadcasting in Holo-conference with Vader for several seconds after impact? Is he standing in vacuum?

Second, in order to make determinations of hull strength from this incident, we would need far more information than we have available to us.

Super-Gagme · Post by **Super-Gagme** » 2004-06-04 11:34pm

It's funny how obvious writer intention is altered so much in minute detail of FX, good thing ol' Georgie never comments a lot on stuff like this

He might make Star Wars worse

McC · Post by **McC** » 2004-06-04 11:48pm

Darth Wong wrote:First, the biggest problem with the idea that the whole bridge tower was totally destroyed is simple: where did all of the material go? Did it fly to starboard and down at super-speed, so that it would disappear from view in milliseconds?

Quite right, and an excellent point. Does the debris cloud/explosion consist of sufficient material to account for both the tower and the asteroid?

And why is the ship's captain still alive and broadcasting in Holo-conference with Vader for several seconds after impact? Is he standing in vacuum?

This I actually have an answer for -- or at least, a possible one. "Lag." Cell phones, for instance, have a second or two delay between what's said and what's heard on the other end, due to the relay time. Something similar could explain why we see what we see. We haven't seen "lag" before in SW, so far as I know, so it's something of a stretch.

The actual time between when the first hint of explosion creeps out from the side of the asteroid to when the captain's signal stops updating (he raises his arm as his signal fades, but his signal 'freezes' as it fizzles, as well -- perhaps something akin to a "framehold" after the signal ends) is 67 frames (@29.97 fps, 2.2 seconds). Alternately, the time between the impact and when he the first 'flash' on the captain's image takes place is 37 frames (@29.97 fps, 1.2 seconds).

What follows is strictly speculative

1.2 seconds isn't too terrible for comm-lag. EM radiation would travel almost 360,000km in this amount of time (the length of Executor more than 20,000 times over), but that doesn't include processing delays, which would be the bigger limiting factor I'd imagine. I again cite cell phones as a modern-day example of this kind of time lag.

Alternately, the bridge itself is in the middle of the bridge tower, and the asteroid hits the port corner...perhaps this has something to do with it, although I can't immediately constuct any realistic scenario to support that idea.

Second, in order to make determinations of hull strength from this incident, we would need far more information than we have available to us.

Well, being the resident expert on materials science, I was hoping you'd chime in on this topic. What other information would we need, just out of curiosity?

Post by **Darth Wong** » 2004-06-05 12:13am

McC wrote:Quite right, and an excellent point. Does the debris cloud/explosion consist of sufficient material to account for both the tower and the asteroid?

It sure doesn't look that way, particularly if one postulates that the tower actually explodes. It should be hurling material out in all directions.

This I actually have an answer for -- or at least, a possible one. "Lag." Cell phones, for instance, have a second or two delay between what's said and what's heard on the other end, due to the relay time. Something similar could explain why we see what we see. We haven't seen "lag" before in SW, so far as I know, so it's something of a stretch.

That might work if the ships were really far away and using lightspeed communications, but they're not. You can see the Executor in the background of the picture.

The actual time between when the first hint of explosion creeps out from the side of the asteroid to when the captain's signal stops updating (he raises his arm as his signal fades, but his signal 'freezes' as it fizzles, as well -- perhaps something akin to a "framehold" after the signal ends) is 67 frames (@29.97 fps, 2.2 seconds). Alternately, the time between the impact and when he the first 'flash' on the captain's image takes place is 37 frames (@29.97 fps, 1.2 seconds).

What follows is strictly speculative

1.2 seconds isn't too terrible for comm-lag. EM radiation would travel almost 360,000km in this amount of time (the length of Executor more than 20,000 times over), but that doesn't include processing delays, which would be the bigger limiting factor I'd imagine. I again cite cell phones as a modern-day example of this kind of time lag.

I'd like to see the cell-phone with built-in comm-lag of 1 second or more. And if they had such long comm-lag, you would notice it on a regular basis. Besides, isn't the delay between impact and supposed destruction of the bridge tower shorter than the delay between the first flash on the captain's image and his supposed eventual dissolution anyway?

Alternately, the bridge itself is in the middle of the bridge tower, and the asteroid hits the port corner...perhaps this has something to do with it, although I can't immediately constuct any realistic scenario to support that idea.

That would be fine if the tower is not supposedly destroyed in its entirety, but that's the problem: people are saying that it's destroyed in its entirety, which is a very difficult idea to reconcile.

Well, being the resident expert on materials science, I was hoping you'd chime in on this topic. What other information would we need, just out of curiosity?

You would need the physical design of the hull structure. You would also need to know what proportion of the impactor's impulse was absorbed by the shield system and what was absorbed by the hull. And you would need to know precisely how much damage was caused by the impact itself, assuming there was no secondary damage from something cooking off inside.

The only thing we can conclude is that the bridge tower must be immensely strong, otherwise a million-ton nickel-iron asteroid would have plowed through it rather than exploding violently on contact. But that's pretty qualitative.

McC · Post by **McC** » 2004-06-05 12:27am

Darth Wong wrote:It sure doesn't look that way, particularly if one postulates that the tower actually explodes. It should be hurling material out in all directions.

There are several large chunks that fly away from the explosion point...

That might work if the ships were really far away and using lightspeed communications, but they're not. You can see the Executor in the background of the picture.

I'd like to see the cell-phone with built-in comm-lag of 1 second or more. And if they had such long comm-lag, you would notice it on a regular basis.

It's not 'built-in' so much as it's a consequence. For instance, if I'm playing music and talking on my cell phone, and the person on the other end is singing along to my music, they're usually off by about a second or so. It's relay/processing time that's the limiting factor, not space traveled. At least so far as I can tell. The idea, however, admittedly begins to break down because it's not consistent, as you point out.

Another possibility might be that the Captain was transmitting from somewhere other than the bridge (although, why?) and he was reacting to a secondary explosion that took place as a result of the impact. Far-fetched, though.

Besides, isn't the delay between impact and supposed destruction of the bridge tower shorter than the delay between the first flash on the captain's image and his supposed eventual dissolution anyway?

Good question. Lemme run the numbers:

Asteroid impacts/first hint of 'explosion': 91
Shot cuts to interior Executor: 121
First flash on holoimage: 128
Holoimage freezes: 156
Holoimage fades: 176

Duration of impact scene: 30 frames/1.0 second
Duration of flash/freeze sequence: 28 frames/0.93 seconds
Duration of flash/fade sequence: 48 frames/1.6 seconds

So they all fall within the acceptable realm of a 1-secondish lag, at least in terms of modern-day communications relay.

An alternative idea (and one that probably best fits what happened from a film-making standpoint) is that we are shown what happens outside first, and then what happened simultaneously inside. Does this break with SoD? If it doesn't, then everything lines up perfectly given the above times. If it does, just another discarded hypothesis.

That would be fine if the tower is not supposedly destroyed in its entirety, but that's the problem: people are saying that it's destroyed in its entirety, which is a very difficult idea to reconcile.

Right. As I said, the idea didn't seem to work to me either.

You would need the physical design of the hull structure. You would also need to know what proportion of the impactor's impulse was absorbed by the shield system and what was absorbed by the hull. And you would need to know precisely how much damage was caused by the impact itself, assuming there was no secondary damage from something cooking off inside.

The magnitude of the explosion would tend to suggest some kind of internal explosion rather than an explosion purely born of asteroid and star destroyer debris, wouldn't it?

The only thing we can conclude is that the bridge tower must be immensely strong, otherwise a million-ton nickel-iron asteroid would have plowed through it rather than exploding violently on contact. But that's pretty qualitative.

Heh. Hull Strength: RFS.

Utsanomiko · Post by **Utsanomiko** » 2004-06-05 01:19am

I do believe that Vader was using holonet transmissions to keep in touch in-person with the ships' bridge Captains (which would also imply the Star Destroyers' shields were down). Suggesting that a form of transmission used for near-instant communication across the galaxy would be plaged by seconds-long 'lag' at ranges of only a few Km (and still be used anyway over other forms of more reliable transmission) is rather absurd.

Connor MacLeod · Post by **Connor MacLeod** » 2004-06-05 02:39am

Darth Utsanomiko wrote:I do believe that Vader was using holonet transmissions to keep in touch in-person with the ships' bridge Captains (which would also imply the Star Destroyers' shields were down). Suggesting that a form of transmission used for near-instant communication across the galaxy would be plaged by seconds-long 'lag' at ranges of only a few Km (and still be used anyway over other forms of more reliable transmission) is rather absurd.

Its proven on page 129 of the Star Wars encylopedia with this image:

The image (and a wealth of other information regarding the TESB shield incident) is found on Wayne's excellent shields page here

As a further note, it sh ould be indicated that in Dark Empire, a "Super Star Destroyer" named Alliegancec had its shields down when transmitting holonet signals, which lends further credence to the notion that one cannot hav eshields up when engaging in Holonet transmissions.

Furthermore, it is universally indicated in the EU that Holonet is a 'real time' or 'instantaneous/near-instananeous' mode of communications, which would not be true if it possessed a 1 second time lag (a second is too noticable, ,sorry.)

(It should also be noted that its unliekly any OTHER form of communications could penetrate shields: standard comm frequencies are similar to lasers, as demonstrated in the Allston novels Iron Fist - when Myn Donos modifies his sniper laser rifle to transmit a comm signal, and again in Solo command when Gara Petothel modifies a TIE laser cannon to transmit comm signals

(Incidentally this also lends further credence to the notion that lasers are speed-of-light weapons, since the EGW&T, and SW.com both indicate that comm signals move at lightspeed.) - but anyhow, since we know weapons fire cannot penetrate sh ields, its unlikely comm signals can either (since for a laser weapon to be used as a communications device, the "medium" through which the transmission is carried must be of a similar nature.
This is not unusual, since a modern laser can be used as a communications device as well as a weapon, or even a sensor. SW "lasers" can also be used as sensors, as well as weapons or "comm" devices.)

Subspace cannot penetrate deflectors either, as per a quote from HTTE (as noted on Wayne's site.)

It should also be noted that on Wayne's site, there is evidence of courier shuttles being used for nonimportant communications, which further suggests that subspace and standard comms would probably not be used (because they would interfere with sensor scans.) Thus, holonet would likely be used (sincee they are less likely to "interfere" with anythign - according to the EGW&T, holonet transmissions are nearly-impossible to intercept.)[/img]

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Asteroids and Star Destroyers (NOT turbolaser-related)

Asteroids and Star Destroyers (NOT turbolaser-related)

Re: Asteroids and Star Destroyers (NOT turbolaser-related)