Okay this may be long winded, but this will be an in depth gander into the science behind turbolasers in Star Wars, like those found on the top of ISDs (Imperial Star Destroyers).
Source : On my profile because I can't put it on the story ( I don't own this, and this source is simply amazing, kudos to whoever made and contributed to it!
Okay, I've been digging around in the science between mere Turbolaser cannons, and, using the laser cannons on the ISD during the asteroid chase in episode 5, the power output of one Turbolaser cannon is absolutely ridiculous, from taking in all the lore about the guns, an accurate guess can be made to gauge the power output of a single turret. In episode 5, a middle-sized laser bolt literally vaporised asteroids estimated to be between around 13 and over 60m wide.
Now, this may not seem like a big deal, especially in terms of weaponry throughout the Star Wars Universe, but into our own universe, and according to our science, an ISD is simply a monstrosity, capable of dealing damage many times the magnitude of the Hiroshima nuclear bomb. The ISD is simply overpowering, but I guess that this was the point, as they were symbols of the Empire's unflinching domination of everything, everywhere.
Okay, down to the science. To get a closer picture of the destructive capability of the Turbolaser, let's look at the ISD in the asteroid field in episode 5, laser blasts were fired from cannons on the ISD, but note that these laser bolts were not fired from the large batteries on the top of the ISD (the ones similar in position with the Venator ships of the Clone Wars).
According to my source, medium sized bolts were fired at asteroids as large as 40m in diameter, when compared to the widely debated size of the Millennium Falcon, and the asteroids were vaporised! Okay, without all the science-y talk just yet, the amount of energy needed to not just break apart, but vaporise an asteroid of that size is huge, like over the energy consumption or a city like London huge, and this is just from rough estimates!
Okay, back to the scary science. Mr Wayne Poe states that:
"More than 90% of the asteroids studied fall into 1 of 2 composition groups: stony iron or carbonaceous. And only a few percent of the meteorites on Earth are carbonaceous. Most of the asteroids in our museums are stony iron, because the carbonaceous ones break up in the atmosphere, or are more susceptible to weathering than the iron ones."
He goes on to say that the asteroid in EP 5 looks to be of the ferrous (Iron) type, due to their rusty red appearance.
Surprisingly, well to me at least, don't know about you guys, but rock actually requires more energy to melt and vaporise than does iron, because as little as 50% of the energy may be absorbed from an energy weapon, depending on the exact composition, with the rest of the energy radiated harmlessly into open space. Assuming that the asteroids are 100% iron, let's say that:
If we assume that a 20m diameter asteroid, 200 kelvin (a measure of heat, so around -73.15 degrees Celsius), and that the asteroids are perfect spheres:
Volume of asteroid = 4188.79 m³
Mass of asteroid = 32,965,759 kg
Heat Capacity of iron = 447 J/kg·K
Initial temp of asteroid = 200 K, normal for objects in space
Final temp of asteroid = 1853 K for melting
Energy for vaporisation of 1 kg of iron: 7.6 megajoules
With these values, a rough figure of around 30TJ(Terajoules) to melt the asteroid, and around 250TJ to vaporise it. Before moving on, wow, like seriously, what the hell. This is one turbolaser bolt! I could go further about the debate of the asteroids' breaking apart rather than vaporisation, but you guys can see that from the source.
Mr Curtis Saxton suggests that the asteroids did not shatter because the process was "supersonic", meaning that the asteroid was vaporised before any of the stress related to the rapid expansion due to vaporisation could take effect. According to the source, this appears to be a valid theory as the vaporisation of an asteroid took around a quarter of a second.
It appears in this scene that the side of the asteroid facing the turbolaser bolt was vaporised, and the resulting liquid/gas then heated and vaporised the remainder of the asteroid. This suggests that the TL bolts are again much more powerful than was simply required to vaporise the asteroids.
However, the boiling point is affected because the asteroids are in vacuum. The boiling point of any material is directly related to the atmospheric pressure surrounding it. In space, the atmospheric pressure is zero. However, at the same time, the asteroid vaporisation was "supersonic" which means that the TL bolts carried MUCH more energy than is required for vaporisation. The vaporisation estimate is on the correct order of magnitude, and actually conservative. It can be used as a conservative lower limit for the power of turbolasers.
The melting/vaporisation of these asteroids took less than a second. The scene lasted about 3-4 seconds, and several asteroids were destroyed during that time. On the widescreen Special Edition, the scene lasted 130 frames. The frame rate is 30 frames per second.
The asteroids required 8-9 frames to vaporise completely. Therefore, it took .225 - .3 seconds for the asteroids to completely vaporise. The power of the TL bolt should be determined by the time the bolt is actually striking the asteroid, which is between 1/15 and 1/30 second (1-2 frames).
Skipping though the less important bits, I saw that each laser bolts were said to be travelling at around 750m per second. Okay, before we move on, let's get this clear. If I am right, lasers are essentially intense beams of light directed at a certain vector. So if lasers are essentially light, and light travels at around 3x10 to the 8 meters a second, rounded up, which is far faster than the turbolaser bolt. This must mean that the laser must be packing some serious mass to slow down to 750m/s.
I'm going out on a limb here and saying that a laser going through space at a significantly slower pace than normal light wouldn't really be possible, as compacting atoms further by decreasing the significant amount of space between the nucleus and the outer electrons isn't really possible due to the strong nuclear force which acts as a really repulsive force at distances lower than 0.5fm(femtometers). But I may be wrong, Mr hawking please correct me if I'm wrong, which I may be, probably, as my personal knowledge isn't great, but I'd like to contribute too rather than just plagiarise.
This is clearly not the case in the film, so the power levels presented here are again very conservative, because the TL bolt duration should be lower (in turn increasing the wattage), as the laser bolts don't take over 2 seconds to traverse the length of an ISD.
Therefore, if we are conservative and use the melting point (more specific figure than boiling point), and use 20 meter asteroids, with the melting figure of ~30 TJ: a medium-sized TL bolt must have in excess of 450 terawatts of firepower, which is a butt-load of power.
Okay, let's compare this to real life. The USA produces around 500-600 gigawatts of electrical power, which is a whole order of magnitude (maybe around 10 times) less than the power of a medium-sized turbolaser bolt.
The Hiroshima bomb was rated at 15 kilotons, translating to around 63TJ, which is about twice that of a medium turbolaser bolt, however, the nuclear bomb directs energy in all directions, and so the energy absorbed by objects around is has got to be less than or equal to half the energy output of the bomb, but a TL bolt directs practically all of its energy at a single target, so a TL bolt would be equal to destructive power of a Hiroshima bomb.
Of course, with the energy required to vaporise the asteroid (~250 TJ), a turbolaser bolt must have on the order of 3750 terawatts of firepower. The energy released would be approximately 4 times more than that of the Hiroshima bomb.
If the asteroids were 40 meters in diameter (and some were much larger), the TLs were directing at least 2000 TJ of energy to vaporise the asteroids, many times the conservative energy level presented above. If the amount of time the bolt is striking the asteroid is 1/15 second (2 frames), 30,000 Terawatts are delivered to the asteroid. Assuming these turbolaser cannons have a maximum firing rate of once every two seconds, they have a sustained firepower of at least 1000 terawatts. The most solid evidence that suggests 40 meter asteroids was in the Avenger-Falcon chase scene, coming out of the asteroid field. One asteroid was at least 60 meters in diameter, which would require at least 6700TJ to vaporise! Another asteroid in a previous scene may have been as large as 100 meters in diameter, requiring at least 31,000TJ to vaporise!
This extract can be found on the source website, and the images would probably help, but I'm not going to be helpful and supply with images, because I'm a scumbag. What are you gonna do.
"The Falcon is leaving the asteroid field, and the Star Destroyer behind is about to. The Falcon is 18 pixels wide, and the more distant asteroid (the large-sized bolt came from the dorsal surface of the ship, and was fired in a starboard direction - not in a ventral direction) is 27 pixels in diameter. Thus, the asteroid is more than 60 meters in diameter. This asteroid would require at least 6760TJ to vaporise. This asteroid was vaporised as easily as any of the others. Thus, this bolt carried much more energy, probably many times more (6700TJ would take some time to vaporise the asteroid, this one took a fraction of a second). This can thus be set as a lower limit on the energy delivered by a long TL bolt. If the bolt's duration is 1/15 second, then it carried well over 100,000 terawatts of firepower.
Given the direction this bolt was traveling, it could not have come from the heavy dorsal batteries. It had to have been fired by the ship's more mundane batteries."
I probably skipped some important bits, but I thought this part would be worth recognising. Many official (non-canon) sources state that a single ISD has sufficient firepower to reduce the surface of a planet to "slag", a term used in ore refining, a result of exposing metal ores to extreme heat.
Okay, I'm simply going to copy this next bit, because it is fairly long winded and tricky to simplify without missing important bits.
If we assume a typical habitable planet, a lower limit on the power of the ISD's complement of TLs can be established.
Mr Curtis Saxton finds that melting the surface of a planet to a depth of 1 meter will require a sustained bombardment with power levels around half a billion Terawatts (i.e.- the ISD must sustain half-a-billion TW during the entire bombardment). The ISD would possibly be melting deeper than 1 meter worldwide, so the actual figure may be much higher than this. This can also be considered the level of firepower an enemy vessel would encounter in combat against an ISD.
Of course, ISDs carry missiles which would be used in such a bombardment, but TLs are considered the primary weapon. Therefore, the figure is on the correct order of magnitude, especially since it was based on depths of only one meter.
If ISDs carry 200 Turbolasers (as suggested by blueprints), then they must average around 2.5 million terawatts of sustained firepower per cannon. Of course, there are different sized cannons, some releasing less power than this, and some more. This power output is comparable to the detonation of a 595 Megaton nuclear bomb every second (per cannon). For comparison, the most powerful bomb detonated to date was rated at 50 Megatons.
The common belief is that ISDs carry 60 turbolasers. This is very conservative, since 64 cannons are mounted immediately lateral to the command superstructure alone, with scores covering the rest of the hull. However, if we assume there are only 60 cannons, then they must average around 8 million terawatts of firepower each. This is comparable to the detonation of a 1900 Megaton nuclear bomb every second, which is stupid crazy. I will probably lower this number, since I will have the empire capitalise on quantity rather than quality, and the USC will only have quality, as only the best survive against the flood.
So, in summary, turbolasers are very, very powerful, and I need to buff halo tech loads by the looks of things to even compare. Medium turbolaser towers have an energy output greater than the Hiroshima bomb, and can glass planets like the covenant did, from orbital bombardment, and using lasers alone, without even considering the other weaponry aboard.
Okay, the rest of the web page goes on about other blasters and lasers in Star Wars, which I may or may not bother with in the next research chapters. So for now, this is the end of the first chapter of research of the science behind Star Wars and Halo.
Okay, next chapter will be the MAC cannons. Enough said.
On a side note, feel free to use this as an information source for any technical information on Star Wars or Halo, so saving you research time. I get that a lot of this is simply copied and pasted, but I feel that I can also contribute towards myth busting Star Wars and Halo, albeit a small contribution as I'm not as incredible as the scientists who can actually put numbers on the capabilities.
Just to make sure, I don't own Star Wars or Halo, but hell I wish I did,
Watermelown