StarDestroyer.Net BBS

I know it's 19 kilometers in length, but what is its mass? Is there a definitive answer? Just curious.

no exact number is ever given as far as I can remember. We can speculate but that's about it.

Has anyone ever calculated the volume? I suppose one could approximate from that. Looking at Saxton's old pages, even he has never bothered. So I would assume the answer would be no.

Another problem is that the density of SW fuel sources is probably high enough that it would exceed the dry weight of the ship. Unless it is stored as complex mass(as in the mass of the fuel is a complex number). This would presumably mean that the mass is contained in hyperspace. It would explain why SW vessels don't explode catastrophically in many notable cases.

The 'volume' should be doable enough, given one is willing to waste enough time and effort on it-there's plenty of pictures of the Executor to work with-but without knowing the average density of the ship (which we didn't even when the old EU was in far as I can recall) that gains you nothing except the volume of the ship. You'd essentially have to assume density to get a mass figure.

exactly the volume is "simple" enough you just have to use the correct integrals for the formula, however without the average density all this gives as is the volume, while using things like car or real life ship densities can give us an estimate we have no way of knowing how accurate that estimate is.

Aren't there cross section images out there? I know there are ones of the ISD. So you could presumably scale up. In fact I imagine that the most practical way to figure out a number would just be to scale up from an ISD (I am assuming we have a mass for those). Sure it won't be too accurate but it should suit his needs.

the problem with that method is that density isn't just what's used and not used, mass on the materials the object in question matters as well, as long we don't exact mass or density numbers, a cross section would really give a a slightly more accurate guess as to the realm mass, however it doesn't mean that guess is anywhere close to being accurate.

AFAIK there aren't any cross-section images of the Executor the way there are of ISDs or Venators. Add to that the fact that also AFAIK we do't have a mass for ISD's either.

Couldn't we use the rough density of a modern or WW2 Warship then multiply that number into the Volume of a pyramid roughly the size of the Executor and get a good ballpark eastimate?

The lady Ex is a pyramid of sorts,but her width is greater than height.

Typhonis 1 wrote:Couldn't we use the rough density of a modern or WW2 Warship then multiply that number into the Volume of a pyramid roughly the size of the Executor and get a good ballpark eastimate?

The Executor can pull an acceleration of 30 km/s². And has shielding that are around 10^24 watts with a total reactor output of 10^26 watts. Given those levels, it would require a fuel source far more dense than what is currently used. With such a fuel source, we would have no real way of knowing exactly how much mass it requires. Regardless of what sort of exotic tricks are used.

Well, we know from ROTS deleted scenes that some ships do store fuel in liquid form. Perhaps they use a hypermatter reactor to convert the liquid fuel into vast amounts of energy that is then used by the ship? Just a thought.

Chris Parr wrote:Well, we know from ROTS deleted scenes that some ships do store fuel in liquid form. Perhaps they use a hypermatter reactor to convert the liquid fuel into vast amounts of energy that is then used by the ship? Just a thought.

well a) we don't know what that fuel is used for b)what's the canon status of deleted scenes anyway?

I might be totally off base about this, but can't you can sort of estimate an upper bound for ISD mass through its estimated power and acceleration, which would not require an estimate for material density?

Upper bound defined by 100% reactor power for maximum acceleration (seems a bit bogus to me, given the need to also power shields and weapons). P=a*mv, so after 1s of burn m = P/av or 1e25W/[3000(m/s^2)*3000(m/s)], or ~1.1e18 kg, so 1.1e15 metric tons for the ISD. Power scales the number linearly, so if it takes 10% max reactor power for maximum acceleration, then it's 1.1e14 metric tons.

I'm sure there must be a math mistake somewhere.

Okay, thanks a lot.

Note that if the ship is modeled as, oh, a triangular slab eighteen or so kilometers long, 1.5 kilometers thick, and six kilometers wide (which are plausible estimates, eyeballing the photos)... you end up with a total hull volume of around 160 cubic kilometers, or around 1.6*10^11 cubic meters.

If the hull actually did mass, oh, 5*10^14 metric tons, that would be roughly... hm... 3000 kilograms per cubic meter.

Which would allow the majority of the ship to be composed of substances as dense as normal metal, leaving roughly half the internal volume for open space or low-density things like water storage tanks or plastics. This is actually improbably dense packing if the ship is made of materials no denser than steel, because most of the steel would be formed into machines that have a considerable amount of internal empty space. Think about a car engine- it's not a solid hunk of iron and weighs a LOT less than a solid hunk of iron of equal mass would.

Alternatively, there could be ultra-dense, exotic and unknown materials that take up a disproportionate share of the mass budget while increasing the amount of empty space in the interior- both the crew spaces and the internal space for machinery's moving parts and for cable access runs and whatnot.

Of course, my estimates are rough, but they give us something like a clue- and they suggest that the Executor's estimated power figures are broadly in line with reasonable estimates for its mass and (insanely high) acceleration.

I find 30 kps^2 pretty pitiful actually and I'm very much afraid a solid hunk of iron the same mass as a car engine would weigh the same, at least of they're both in the same gravity well.

He clearly meant volume and mistyped. It happens.

I forgot the damned smiley again didn't I.

Batman wrote:I find 30 kps^2 pretty pitiful actually...

Three thousand gravities is 'pitiful?' Compared to what fantasy of non-Newtonian speediness?

Or is this you forgetting the smiley again?

and I'm very much afraid a solid hunk of iron the same mass as a car engine would weigh the same, at least of they're both in the same gravity well.

Rogue 9 wrote:He clearly meant volume and mistyped. It happens.

Rogue 9 is correct- I did not catch the typo.

I knew I made a math error - acceleration should be 3000*9.8 ms/s^2, so if an ISD uses ~10% power (1e24W) to accelerate to 3000g, then mass estimate is ~1.1e13 metric tons

Hm. That would actually be rather on the light and fluffy side, unless I'm greatly overestimating the volume of the ship.

that said all SW ships have anti-grav tech so that might effect the calculations.

Simon_Jester wrote:

Batman wrote:I find 30 kps^2 pretty pitiful actually...

Three thousand gravities is 'pitiful?' Compared to what fantasy of non-Newtonian speediness? Or is this you forgetting the smiley again?

Nope. Sci-Fi wise I grew up on the Perryverse. For me capital ship accelerations start at 500 kps^2. And those engines actually were Newtonian (not real world physics by any stretch of the imagination but definitely reaction engines).

Lord Revan wrote: that said all SW ships have anti-grav tech so that might effect the calculations.

I don't see why. Mass manipulation technology would, but that's not necessarily thew same tech as anti/countergravity. Anti/countergrav wouldn't do much outside a significant gravity well.

Simon_Jester wrote:Hm. That would actually be rather on the light and fluffy side, unless I'm greatly overestimating the volume of the ship.

That's an estimate for an ISD, since we have better power figures for that. I would use that to scale based on hull volume to get a figure for the Executor, plus some more scaling factors since density would probably increase as size expands.

[blinks]

How did I miss that... D'oh.

Well, we can get at least a crude approximation by saying Executor is ten times bigger in every dimension and a thousand times heavier...

Anyway, an ISD that masses ten trillion tons would be insanely dense, with well over ten thousand tons of mass per cubic meter of hull, since the ISD has considerably less than one cubic meter of volume to begin with.

This strongly suggests that the ISD's engines are not a major power requirement, and that the ship is designed to operate at full engine power while still having even greater energies available to run the guns and the shields (and the sensors?). Alternatively, it means ISDs contain large amounts of degenerate or collapsed matter, because nothing else is dense enough to explain a ship that weighs ten thousand tons per cubic meter.