[Spaceships] DS-1 Orbital Battle Station
 

Here it is, the one spaceship that many folks have told me not to toss at them! The original Death Star!

DS-1 ORBITAL BATTLE STATION
aka the Death Star

TL: 11^
dHP/ST: 700K
Hnd/SR: -9/5
HT: 13
Move: 0.5 G/c
LWt: 1,000T tons
Load: 50T tons
SM: +32
Occ: several million ASV
dDR: 200,000
Range: -
Cost: $111.6 QT (for mass production; as a one-of-a-kind deal, higher by at least a factor of 10, probably closer to a factor of 100)
Streamlined: Yes (it's a sphere, after all)

Front:
[1] Armor, Diamondoid; dDR 200,000; $10QT
[2!] Weapons Battery, Spinal-Mount; 100B workspaces, $15QT
[3] Control Room; C21 computer, Comm/Sensor 32, 300,000 stations, 100B workspaces, $2QT
[4] Habitat; 6,000,000,000,000 cabins, 100B workspaces, $1QT
[5!] Weapons, 100,000 SM +22 Tertiary Batteries; 100B workspaces, $6QT
[6] Cargo Hold; 50T tons

Middle:
[1] Armor, Diamondoid; dDR 200,000; $10QT
[2] Habitat; 6,000,000,000,000 cabins, 100B workspaces, $1QT
[3] Hangar Bays; Capacity 30T tons, launch rate 2B tons, 100B workspaces, $100QD
[4!] Weapons, 100,000 SM +22 Tertiary Batteries; 100B workspaces, $6QT
[5] Habitat; 6,000,000,000,000 cabins, 100B workspaces, $1QT
[6] Habitat; 6,000,000,000,000 cabins, 100B workspaces, $1QT
[core!] Weapons Battery, Spinal-Mount; 100B workspaces

Rear:
[1] Armor, Diamondoid; dDR 200,000; $10QT
[2!] Weapons Battery, Spinal-Mount; 100B workspaces
[3] Habitat; 6,000,000,000,000 cabins, 100B workspaces, $1QT
[4!] Rotary Reactionless Engine; 0.1G accel, 100B workspaces, $500QD
[5!] Stardrive Engine; 100B workspaces, $10QT
[6!] Weapons, 100,000 SM +22 Tertiary Batteries; 100B workspaces, $6QT
[core] Power Plant, Super Fusion; 4 PP, 400 yr endurance, 100B workspaces, $30QT

Design Features:
Artificial Gravity; $1QT
Total Automation; $8T

Design Switches:
FTL Comm Array

Spinal-Mount Weapon Battery:
1 ZJ Ghost Particle Beam
dDamage: 2d x 1,000,000,000 (infinite) cr ex
Range: X+
Rcl: 0
sAcc: -3

Forward Tertiary Weapons Batteries:
3,000,000 10 TJ Particle Beam Turrets (turbolaser turrets)
Options: Improved
dDamage: 4d x 100 (5) burn rad sur
Range: L/X
Rcl: 0
sAcc: -3

Mid-Section Tertiary Weapons Batteries:
2,950,000 10 TJ Particle Beam Turrets (turbolaser turrets)
Options: Improved
dDamage: 4d x 100 (5) burn rad sur
Range: L/X
Rcl: 0
sAcc: -3

50,000 10TJ Tractor Beams
dDamage: 4d x 100 spec
Tractor Force: 1,000,000 tons
Range: L/X
Rcl: 0
sAcc: 0

Rear Tertiary Weapons Batteries:
3,000,000 10 TJ Particle Beam Turrets (turbolaser turrets)
Options: Improved
dDamage: 4d x 100 (5) burn rad sur
Range: L/X
Rcl: 0
sAcc: -3

Design Notes:
1. The Ghost Particle beam is the best fit I could find for the Death Star Super-Laser at the specified TL. Boosting it to a one-of-a-kind TL 12^ innovation is also possible.
2. I had a bit of flak from some folks on IRC about using "Particle Beam" for the turbolaser, with folks pointing out obscure citations "proving" that turbolasers (and blasters, for that matter) are not particle beams, despite the overwhelming number of citations in which they are described as such. I therefore challenge folks to come up with a better fit if they feel it necessary.
3. I have not broken down the Habitat section for one simple reason: With 24,000,000,000,000 (24 trillion) cabins, would you attempt it?! :)

Abbreviations:
T = Trillion (10^12)
QD = Quadrillion (10^15)
QT = Quintillion (10^18)
ZJ = zetta-Joule


I don't know whether I'll do the DS-2 Orbital Battle Station (Death Star II); any stat block would be its finished version, not the unfinished-yet-operational version as seen (and blown up) in the third movie. The DS-2 has a diameter of 900 km, or roughly 560 miles, which would be SM +34, boosted to SM +36 due to its spherical shape.

Re: [Spaceships] DS-1 Orbital Battle Station
 

Looks good. I did the calculations for the size of the two Death Stars a while ago, and got the same results as you, so I think that's correct. I would not call it Streamlined however; the reduced armor efficiency of that option is due to a vessel having a higher-than-expected surface-area-to-mass ratio (due to the long narrow body and sculpted hull segments) while a sphere has, by definition, the smallest possible surface-area-to-mass ratio.

I'm not sure how you're getting 2dx1B for the Spinal Mount. A 1ZJ Ghost Particle Beam should deal 2dx100,000. It may be a typo, or you may have misunderstood the scaling of beam weapons. Of course, 2dx100K isn't sufficient to destroy a planet, even when tripled for an internal explosion; an Earth-sized planet is roughly SM +45, for 100M HP. So it could be that you've just handwaved a hugely inflated damage score to allow it to achieve that feat. After all, even adding the Cosmic Power modifier to the Superlaser (bumping it up to 1 Yotta-Joule) would only increase damage to 2dx1M, requiring five shots to drop a terrestrial planet to 0 HP, and far more to reduce it to rubble. It could be that the weapon is "double Cosmic", delivering 1000 YJ, or 2dx10M, enough to force a death check in one shot. Also, I'd recommend a TL12^ Conversion Beam as a better match for the Superlaser. You really don't need all that much armor penetration; an Earth-sized planet has only DR 2M*, so any weapon capable of damaging the planet will not even notice its DR.

All of this means, of course, that the other powered systems have negligible drain compared to the main gun, which is entirely appropriate. I'd suggest bumping up the cost of the Spinal Mount and Reactor by a couple orders a magnitude to represent the tremendous power they can deliver.

*I think I based that on a SM +45 Spaceship composed entirely of Rock "Armor". And even that may be excessive, since the crust is quite a thin layer, and the mantle and core may be less resistant to penetration.

Re: [Spaceships] DS-1 Orbital Battle Station
 

It's probably a typo. I don't think I misunderstood the scaling, as I was working off a spreadsheet which did the scaling for me for a lot of stuff, but... Well, weapon damages wasn't one of the things I spreadsheeted.

And then there's the other explanation! :)I kinda like this explanation for my oops. Give yourself a no-prize!

Good point! I'm not going to do it now, but what factor would you multiply them by?

Re: [Spaceships] DS-1 Orbital Battle Station
 

I'd put it in my no-ship, but I can't find the damn thing.

At least x10, maybe more for the Superlaser. At x10, this increases the overall cost to $516.6 Q. Of course, this is not a ship that you really need to work out the cost for, unless you just want to see how many entire starsystems need to be utterly plundered to build it. And even then, GURPS isn't really an accurate economic simulator, especially when looking at the Spaceships rules. Ultimately its price is a matter of plot rather than economics.

Re: [Spaceships] DS-1 Orbital Battle Station
 

Gyuh. This is why I would never run a stock setting, only something "inspired by". Freaking cannon nazis.

I'd do it by percentages. 80% hab, 5% luxury, 5% entertainment, 5% medical, etc.

Re: [Spaceships] DS-1 Orbital Battle Station
 

If you want to be fussy, Mike Wong has demonstrated that the Death Star superlaser would have to release 10^32 to 10^38 J of energy to overcome the gravitational binding energy of an earthlike planet (the superlaser didn't just melt or shatter Alderaan, it scattered the pieces so that they didn't immediately fall back together). Add some energy to overcome the planetary shield. Star Wars technology involves gobsmacking amounts of energy. I wouldn't worry about what type of particle the turbolasers or superlaser shoot, since its pretty clear that they don't match our physics.

Re: [Spaceships] DS-1 Orbital Battle Station
 

Haha! "Cannon" + "thread about Death Star superweapon" = Faint to moderate win. Have an e-donut good sir.

Also, thanks to tbrock for statting this up. I'm off to compare it against Spaceships and Space and figure out how you did it all.

Re: [Spaceships] DS-1 Orbital Battle Station
 

The defenses are supposed to be designed around a direct, large-scale assault, with small, one-man fighters an afterthought. Shouldn't you have more weapons on a capital-ship scale, and fewer tertiary batteries?

Star Wars ships have deflector shields, no? It's a bit bumpy for those one-man fighters to penetrate the one the DS has.

The crew/cabins/workstations count seems pretty high. Did the Empire depopulate thousands of planets just to crew the Death Star?

Re: [Spaceships] DS-1 Orbital Battle Station
 

Note that the turbolasers are already scaled as if they were mounted on a SM +22 ship. Even a ship of SM +22 has a hard time hitting SM +5 fighters. Note the damage (which I should go in and edit to read "dDamage"), 4d x 100 (5), being in the 10 tera-Joule power range. These guns can hit and do damage to most of the capital ships, and with several thousand of them firing at once, well... I suspect they'll hit something.

Note the quote. "We're passing through the magnetic field." They're indicating that the DS has a magnetic field similar to that of a larger planet, not a deflector shield, which likely comes from its moon-sized, heavy-iron layout.

That Red and Gold squadrons were able to pass through the field with their own deflectors on tells me it the Death Star did not have a deflector shield large enough to cover it. If it was a deflector shield, the fighters would have simply impacted against it and blown up (which happened to a few fighters, at least in the novelization, against the second Death Star when they failed to pull up in time following Lando's realization that the shield was still up, and that shield was generated from a nearby planet/moon).

The official stats indicate a population in the millions. I gave the Death Star total automation (for $8T, a drop in the Death Star's budget), so those workspaces are just for reference, not actual; the crew itself still numbers quite high, which would be expected for a space station 100 miles in diameter. Also note that a lot of that "crew" would likely be droids or (Wookiee) slaves, not actual Imperial human personnel.

As for the cabins, as I indicated in the original post, the habitat section - which included living quarters for the several million crew and civilian contractors on board, as well as the establishments (one owned and operated by an Alderaan native, no less), medical facilities, trash compactors, training areas for the 501st Stormtrooper Division and 181st TIE Fighter Squadron, dianoga petting zoo, etc. - has not been broken down. The Death Star was a mobile city as well as a military installation, after all.

Re: [Spaceships] DS-1 Orbital Battle Station
 

I consulted the ever-helpful Boom Table from the Atomic Rockets site, which suggests 2.9x10^32 J for the destruction of Earth. I did a few simple calculations and got a damage of roughly 5e14 (that is, 500 Trillion points of damage) required to blast an Earth-sized planet into gravel with enough velocity to exit orbit and continue indefinitely. That may not necessarily be the level of destruction caused by the Superlaser, however. If the chunks remain within the same solar system, the damage drops to ~2e14; if it doesn't actually blast the bits out of the same orbit it only needs ~1.5e14 damage. This suggests that the Earth has around 15 Trillion HP - a very different result than what's given using just the GURPS SM scaling, which is to be expected.

The Earth has a mass of about 6.6e21 tons, which normally gives 1.9e9 (1.9 Billion) HP for a Homogenous body. Using the more generous and realistic HP calculations from Pyramid 3/34 (based on square root of mass instead of cube root) gives 1.2e13 (12 Trillion) HP, falling very close to the amount calculated above.

To achieve such extreme damages, you could either arbitrarily declare that the Superlaser is sufficiently powerful, or take a look at another option from Pyramid 3/34, "The Square Root of Destruction". Like the above option for HP, this changes the calculation from cube-root of energy to square-root. A "double Cosmic" SM+32 1000YJ Spinal Mount would deal dDam 9dx10B, or around 12.6 Trillion for a Conversion beam, still a little short of what's required. You need to get into the 100K-1M Yotta-Joule range to reliably vaporize a planet (126-420 Trillion damage). This is effectively a SM+48 to +50 Spinal Mount, and thus requires extreme handwavium to squeeze into a mere SM+32 planetoid.

There are alternatives to brute force, however. If the Superlaser could set up some sort of chain reaction within the planet's core, it could perhaps destroy it with a far milder energy output. This is still blatant superscience, but it at least doesn't directly violate the maximum energy density of matter. IIRC, the Sun Crusher (a superweapon that shows up in one of the Expanded Universe novels) did basically the same thing with a star, triggering a supernova. Likewise, a similar concept shows up in Star Trek (the Genesis Device from ST2:Wrath of Khan, and Trilithium missile from ST7:Generations). Perhaps the clearest example of this idea is the Molecular Disruption Device from Ender's Game, which will instantly destroy any object, converting its entire mass into an expanding sphere of annihilation.