30-11-2000 21:49									#1
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Could someone with knowledge of physics possible calculate how much energy a singularity PB delivers, based on how much land it vapourizes? Please? .
Oh yeah and I'm new btw, but I've read these forums on and off since the really old Firaxis forums, so hi!

	30-11-2000 23:32									#2
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It shouldn't be too difficult. I think somewhere you can look up the crater size of existing nuclear weapons...use the megatons to calculate the energy. The only question I have is what is the scale of the map related to real world units?

	01-12-2000 20:16									#3
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Well for size I guess I could assume that the Huge Map of Planet was the same size as Earth. Do you have any idea where I could find Nuke craters and energies, though?

quote: Originally posted by hellrazor on 11-30-2000 01:32 PM It shouldn't be too difficult. I think somewhere you can look up the crater size of existing nuclear weapons...use the megatons to calculate the energy. The only question I have is what is the scale of the map related to real world units?

	04-12-2000 19:47									#5
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According to Flavor.txt, the effective kill radius of a planetbuster is 2,000 km and the explosive force is 296 gigatons of TNT (compared to the largest atom bomb ever detonated, equivalent to 60 megatons of TNT). Of course, this does not factor in the reactor power.
If one assumes the Huge-level map to be equivalent to the size of the Earth, then the length of an individual square can be determined to be (Circumfrence of Earth / Length of Huge Map) = (4.00 * 10^7 / 127) = 3.15 * 10^5 km. As a singularity Planet-Buster destroys a circle with diameter 7 squares = 2.21 * 10^6 km, we can calculate its comparative explosive force relative to a nuclear weapon of known explosive force. An airburst 1-megaton warhead has a total destruction radius of 1.55 kilometers. However, this is only the radius in which the blast pressure exceeds 50 psi and it varies depending upon altitude the weapon is burst at, weather conditions, and numerous other factors. The radius of _effective_ destruction, in which it is effectively impossible for a military unit to survive in a way which would permit it to be able to function, should be considered to be perhaps 5 km from a 1-megaton weapon-once again, this is only an estimate, as altitude of detonation, whether or not it is an air- or ground-burst, how well the unit is sheltered, weather conditions, etcetra have a great effect. As the explosive force of a nuclear weapon (according to _Nuclear War Survival Skills_, by Cresson H. Kearny) increases by a factor of roughly 110 for every 1,000-fold increase in megatonnage, we may therefore calculate the explosive force of a Planet-Buster as follows:

1. The ratio of the kill radius of the Planet-Buster to a 1-Megaton Nuclear Weapon is ((1.10 * 10^6 km) / (5 km)) = 2.21 * 10^5.
2. The number of 1,000-fold increases in explosive force may be estimated by log (base 110) (2.21 * 10^5) = 2.62.
3. Therefore, the explosive force may be considered to be 1 megaton * 1000 ^ 2.62 = 71,267.95 gigatons, or about 71 terratons.

	04-12-2000 21:22									#6
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First off I know this is Sci-fi and all but, with that much energy one would think that the effects of the blast would be more profound than displayed in the game.

Chiron's mantle would be cracked wide open allowing magma to be spewing all about. The blast itself most likely would throw Chiron off it axis of rotation thereby likely making the planet inhabitable. Likely other effects might be a orbital change to a more elliptical orbit 'round the dual suns as well.

My own thoughts on the Quantum and Singularity PB's is that the effects are not a blast per se but a great implosion causing the area of effected matter to be sucked into a temporarily formed singularity. The black hole then winks out of existance taking with it all sucked up matter inthe process.

Jus my 2 cents

Og

	04-12-2000 21:54									#7
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It all depends on how you deliver the energy. For that matter, one thing Firaxis neglected is that all you would have to do to severely injure someone is take a dinky little fission planet-buster and detonate it in orbit over their continent. The resulting energy would be entirely transformed into an electromagnetic pulse. Way back in the 50s, we did something similair with a little atom bomb only worth a couple of kilotons, and it tied up communications for monthes all over the globe. A space-burst PB would fry every piece of electronics the target had, plus a lot of everyone else's. At least equivalent to the random event where you cannot talk to anyone for ten years...

	05-12-2000 05:13									#8
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Grav,

What we see as a Planetbuster is more like a large asteroid impact. Current nukes are, as LeMark mentioned, primarily airburst to cause maximum damage to the poor little humans and their frail buildings, which are destroyed by the mass movement of superheated air. When exploded underground they make nary a dimple – not impressive. This does not even come close to a crater 2,000+ kms in diameter that is caused by a PB. The only analogy I can think of is the enormous remnant crater in the Yucatan peninsula in Mexico from about 65 million years ago (which, incidentally, is the leading contender for what whacked the dinosaurs at the end of the Cretaceous period).

Moreover, the energy released/converted between a meteor and a PB is similar, too. I’d have to dig a bit to verify, but even a medium sized asteroid impact releases orders of magnitude more energy than our largest H-bomb, and any nuke is puny by comparison. I also remember reading somewhere in an old tectonics text that if all the nukes in the world were exploded at a single point that they wouldn’t even move a portion of the Rockies a thousandth of an inch. Another interesting comparison is the energy released by an earthquake, which also makes nukes seem pretty puny. So, would a PB throw Planet out of its orbit? Nope - the energy to mass ratio is just too small. It would take an impact like a small moon or planet to throw an object like the Earth off its orbit a bit. Of course, that is academic since a planetary impact would be fatal for a planet’s ecology even if the planet survived. (Note – Uranus has a tilted axis – the only one in our solar system, and some hypothesize that a planet-sized object hit it a long time ago; likewise, the Earth’s moon may be the result of a very large object whacking Earth during its formation, with the objecta forming the moon).

All this drivel aside, a PB should have significant ecological impacts (e.g. – global cooling due firestorms and asteroid-crustal particulates thrown into the atmosphere, etc.) just like a massive meteor strike might do. Even our little nukes might be enough to ruin Earth, if we are ever stupid enough to use a good number of them. I see this as a major oversight on Firaxis’ part, since warring factions can lob PBs on each other and suffer no more than a little eco damage and a MW onslaught or two. By comparison, it would be a major drag if all cities over all of Planet got a –1, –2, or –3 food/hex for 20 years. Racial suicide? I think so.

Hydro

	05-12-2000 08:59									#9
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A quick comment on global cooling caused by mass usage of nuclear weapons (a.k.a. "nuclear winter): this is actually a myth whose supporting science can be easily undermined. The method by which the smoke released into the atmosphere was calculated was to simply find out how much a nuclear weapon of X tonnage released and then multiply that by the total megatonnage. The actual ratio of dust released to explosive force is a lot smaller than 1:1...

	05-12-2000 18:07									#10
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LeMark - “Myth” is a little strong. It might be more accurate to say that there is disagreement in the scientific community (which is in abundant supply). The only way to find out for sure is to have a PB-style war, but I’ll pass on that test of the hypothesis.

	06-12-2000 08:07									#11
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I have to agree with LeMark on this one (nuclear winter) if indeed he is correct in his representation of how the analysis was conducted. Even a specially designed 'Nuclear Winter Bomb' would not be able to take advantage of a 1 to 1 relationship between explosive force and smoke / dust creation.

Seperately, does anyone know whether nuclear weapons are designed to take advantage of 'shaped charge' dynamics (my guess is yes) or are they just big explosive charges that spray death willy nilly mostly into the air?

	06-12-2000 11:21									#12
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My refrence on the methods used to calculate nuclear winter is pretty reliable, as he used to be one of the scientists who worked on the Continuity of Government (CoG) projects for the federal government.
And as for the question on shaped-charge dynamics it really depends on the bomb and the target. The Soviets deployed 20-megaton bombs using such methods for use in cracking open facilities like NORAD and Ravenrock Mountain. Other warheads, like the strategic city-busters and the little hundred-kiloton jobs used to crater runways and take out semi-hardened targets, really did not need that sort of enhancement-it would simply be overengineering.
The US, incidentally, recently tried to develop a derivant of an existing nuclear warhead designed specifically to take out underground, hardened targets. I believe we postponed development when the Russians started screaming-after all, we _did_ sign a treaty with them not to design new types of nuclear bombs...

	08-12-2000 18:35									#13
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Did a little research to compare the energy required to create large-scale cratering by using meteorites as a mechanism (e.g. – a way to deliver energy to cause a desired effect). The 2 billion-year-old Vredevoort crater in South Africa is 140 km across, and it is estimated that it could be created by a 10-km diameter asteroid traveling at 50 km/s. The energy required for this crater is about one billion (one thousand million) megatons of TNT. To put this type of meteorite to scale, the Earth’s breathable atmosphere is about 10 km thick, Mt. Everest is 9 km high, and the average ocean depth is 3.7 km (deepest 11 km).

You could scale this crater up to 2,000 km, but why bother. Just one of these puppies is a global catastrophe. With that much energy released (or even a fraction of it) there would be no question that there would be severe ecological damage, and that it would blow away any current ‘nuclear winter’ model (which, btw, were first hypothesized by Carl Sagan and friends after the meteorite hypothesis of global extinction was advanced in the early 80s). At this point you don’t worry about the critical and controvertial elements of the nuclear winter model (generation of particulates and the mechanism to convey them to the troposphere) since you have just vaporized a 140-2,000km craters worth of rock and water and have blasted a nice, big hole in the atmosphere.

Oh, Ogie, you were right. The Vredevoort meteorite likely blasted down to the mantle, exposing lots of nice, hot magma as the thin veneer of rock above it was vaporized. I’d hate to think what would happen during the creation of a crater an order of magnitude larger.

Bummer.

Hydro

	08-12-2000 20:33									#14
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Wow, thanks everyone. LeMark, do you think I could use those calcs in debates on Spacebattles.com (a place for debating which Sci-Fi universe would beat which other one)? I'd be sure to credit you of course. I think with weapons that powerful SMAC beats just about everything short of the Culture .

	09-12-2000 10:34									#15
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Thanks, -gravity-. Feel free.
And meteor impacts and large-scale planet-busters would undoubtedly create something similair to nuclear winter. It is only with regards to large-scale nuclear war, using weapons presently deployed, where the the current calculations are inaccurate.