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starbase1
10-12-2006, 03:02 PM
The conventional wisdom in 33d graphics cicles (though not in astronomy), is that space scenes should have one simple bright distant light, with pitchblack shadows.

You might care to consider the awesome image here:

http://saturn.jpl.nasa.gov/multimedia/images/image-details.cfm?imageID=2316

It's worth trying to describe what you are seeing. The Sun is directly behind Saturn as seen from the Cassini probe. The edge of Saturn is bright because the atmosphere is lit around the rim by the sunlight. The back of the planet is lit by light reflecting off of the rings, (which are not visible from the poles, so they are dark). You can also see the shadow of the rings in Saturn's atmosphere at the top part of the globe...

Nick

Kurtis
10-12-2006, 03:08 PM
Nick,

Are you looking at the Color Exaggerated Version or the Original Version? In the Original Version, the back of the planet is pitch black.

Edit: I take that back, I can see some color reflected onto the planet from the rings in this one.
http://photojournal.jpl.nasa.gov/jpegMod/PIA08329_modest.jpg
I am surprised that the rings carry light all the way around the planet.

SplineGod
10-12-2006, 03:09 PM
It depends if youre talking about lighting a space ship in deep space away from gaseos regions vs lighting a planet surrounded by gasses. :)

colkai
10-12-2006, 03:19 PM
Aww, you know space lighting is simple, don't be silly.
Every starship comes complete with it's own lighting rig which follows it everywhere, I mean, you have seen Star Trek haven't you. ;) :p

T-Light
10-12-2006, 03:23 PM
Colkai -

Every starship comes complete with it's own lighting rig which follows it everywhere, I mean, you have seen Star Trek haven't you
Are you looking at the Color Exaggerated Version or the Original Version? :D :neener:

Kurtis
10-12-2006, 03:31 PM
Yeah, now there's a realistic view of the future. :rolleyes:

Nick, I hope you don't take my original post wrong. What you posted interested me, so I went to check it out. Maybe I'm just looking at the wrong images.

starbase1
10-13-2006, 12:48 AM
Yeah, now there's a realistic view of the future. :rolleyes:

Nick, I hope you don't take my original post wrong. What you posted interested me, so I went to check it out. Maybe I'm just looking at the wrong images.

Not at all! I had to do the same thing myself - there's a guy on the International Astonomical Artists list who works with the raw data - he pointed out a mass of subtleties. Took me a whileto work out what was going on with the rings and shadows at the edge of the planet too!

colkai
10-13-2006, 03:35 AM
Colkai -

Are you looking at the Color Exaggerated Version or the Original Version? :D :neener:
Hey, it's Star Trek, it's ALL exaggerated. ;)

Seriously though, those images are astounding, you always read about how little light there is "out there", can you imagine the amount of light bouncing going on within the rings to create the light bleed on the dark side?

How long do you reckon a "true" render of those bounces would take? :p

starbase1
10-13-2006, 03:43 AM
There's another shot with the Earth and Moon visible through a gap tin the rings! (The moon is only a lump on the edge of Earth, but it is there).

For the light of the rings back on the planet, and onto the rings again, it should be a straightforward 2 bounce radiosity for a first approximation.

Of course, if tyou really want to take account of the way that light and colour is affected by the dirrerent scattering modes and particle sizes, you cabn do what the awesome Bjorn Jonsson did, and write your own planetary renderer!

His maps are amazing, and it was on his pages that I first saw an assessment of the effect of radiosity lighting on the real planet Saturn...

http://www.mmedia.is/~bjj/planetary_maps.html

Nick

Dave Jerrard
10-13-2006, 11:06 AM
Nick,

Are you looking at the Color Exaggerated Version or the Original Version? In the Original Version, the back of the planet is pitch black.

Edit: I take that back, I can see some color reflected onto the planet from the rings in this one.
http://photojournal.jpl.nasa.gov/jpegMod/PIA08329_modest.jpg
I am surprised that the rings carry light all the way around the planet.Saturn is the only planet that actually has an illuminated dark side, thanks to light bouncing off the rings. Probably one of the most extreme examples of natrual radiosity. A few years ago I set up a scene to try to duplicate a Voyager photo that showed this off. That photo, and my LW version can be found here (http://www.cgfocus.com/interview/story/52&page=6) (click for a larger image). I only did some slight processing to get my vesion to match the colors in the photo (for some reason this original was more of a greyscale), though I do have others that are more naturally colored.

Lately, I've been wondering about getting the rings even more accurate, now that we have nodes to play with. I've done some experiments that seem to be promising. The biggest deals with nodes are that they now allow me to do a better translucency effect, and I can independently color the rings for forward & backscattered light a little more easily and accurtely.

He Who Can't Wait Until Saturn is High In The Sky Again In A Few Months.

Dave Jerrard
10-13-2006, 11:25 AM
Hey, it's Star Trek, it's ALL exaggerated. ;)

Seriously though, those images are astounding, you always read about how little light there is "out there", can you imagine the amount of light bouncing going on within the rings to create the light bleed on the dark side?

How long do you reckon a "true" render of those bounces would take? :p
Actually, there's a pretty sharp edge of the shadow on the rings. In that photo, what you're actually seeing is the light bouncing from the rings onto the back of the planet, and you're seeing this through the unlit portion of the rings. Now, with a little exposure adjustment, some light bouncing from the rings to the planet will bounce back and illuminate the shadowed area of the rings, so technically, they're all being illuminated to some degree (even by star light (http://antwrp.gsfc.nasa.gov/apod/ap040313.html)), but with normal human-perceptible ranges, these areas are still dark.

If you look closely, you'll notice a black edge just between the planet and the rings on the lower half of the image. This is the shadow of the planet. It's a little more noticeable on the right since the sun's just behind the limb of the planet in the lower left. You can also see a dark band along the equator, where the rings are facing the planet edge-on, so they're not bouncing very much light that way (much like how an area light works). Most of the light gets scattered above or below the rings, and doesn't scatter very far along them (at least not intense enough to be very visible).


He Who Did Try A Render Of Asteroids With Radiosity, But Gave Up On It.

Lottmedia
10-13-2006, 12:04 PM
I rememeber talking to some scientist friends of mine years ago about spacetravel and how they were annoyed with things like StarTrek and battlestar gallatica and star wars because the idea of visually piloting a spacecraft was absurd. With the visual conditions and extremem distances involved it would be just impossible. Granted, the Battlestar and Star Wars dogfights wouldn't be nearly as intresting to watch if it were guys watching a readouts on a screen and never actually seeing anything. So much of what we have today is the offspring of "Space Opera" and not "Science Fiction" there's very little science in our fiction today (oh my god, I sounld old!)

Casey :cat:
(Now I am sad :( )

Dave Jerrard
10-13-2006, 01:39 PM
I rememeber talking to some scientist friends of mine years ago about spacetravel and how they were annoyed with things like StarTrek and battlestar gallatica and star wars because the idea of visually piloting a spacecraft was absurd. With the visual conditions and extremem distances involved it would be just impossible. Granted, the Battlestar and Star Wars dogfights wouldn't be nearly as intresting to watch if it were guys watching a readouts on a screen and never actually seeing anything. So much of what we have today is the offspring of "Space Opera" and not "Science Fiction" there's very little science in our fiction today (oh my god, I sounld old!)

Casey :cat:
(Now I am sad :( )I was talking about this stuff with my several times lately. I really got to think about it (well, not so much think as have the idea just slam my head) when I saw the pilot for the new BSG. All thos ebullets flying around in space.. Yikes. After about a minute, it would be deadly just being anywhere near the region of a space battle, let alone actually participate in it. Rules for space combat vs aerial combat would be completely different. B5 got some of it pretty good, like spinning a ship 180 and firing on a ship behind you without even affecting your trajectory. But you definitely don't want to stay in the area of a comabat too long. One exploding ship can take out a lot around it for a while, as all that shrapnel keeps on going, and going... I always wondered where all the small bits of exploding ships went when the fire cleared in movies.. And how the ships that blew them up were unscathed as they flew THROUGH the exploding ships. ****. I haven't seen any half decent air to air combast sequences since Top Gun.


He Who Should Do An Accurate Space Battle Sometime.

Scazzino
10-13-2006, 02:01 PM
I particularly like how the ships are usually all oriented with the same "up" direction during a battle... and how there's lots of noise...

Stooch
10-13-2006, 02:24 PM
i find it funny how ships dont get affected by the recoil of their weapons which probably produce as much kinetic energy as the thrusters. Yeah the up vector is funny, the loud noises and droning ala star wars is hillarious. And the fact that there are fiery explosions, i think at most you would see in space is glowing debree flying about (which would cool extremely fast) and maybe a bit of fire if a fuel cell explodes or something.

i think the reality of space combat would be very boring and very painful. you could be sitting in your solar system and a kinetic projectile could just come out of nowhere and pierce your hull and suck you out to space silently but disgustingly and no one would be the wiser.

Dave Jerrard
10-13-2006, 02:25 PM
I particularly like how the ships are usually all oriented with the same "up" direction during a battle... and how there's lots of noise...
I can see a reason for the 'up' direction, but as for the sound in space, well, that's just insane creative license... I noticed they did this right with Sernity - no sound in space, and the sound wasn't even missed. But audiences I guess just don't get it, and expect every flash to have a matching boom, or it's the directors that don't have a clue. Hard to say.

As for up, that does make sense. In a planetary system, you'd probably orient your ship along orbital plane. It's easier to wrap your head aroud navigatin this way. We do the same thing with software, like Starry Night, etc., by having the orbits, as seen from an arbitrary outside perspective, rotate from vertical to horizontal. It's easier to to deal with more most people. Outside a solar system, you'd probably orient to the galactic plane for the same reasons. Also, this work for another reason. Think of a space battle, or even just docking procedures. For docking reasons, you'd probably wnt to have as little complexity as possible involved in aligning two ships. So if they're alreay nearly aligned by default, you taken a good chunk of possible problems out of the procedure.

For combat, nearly every ship seen in any SciFi tends to be wider/longer than it is tall. When seen from the side or front, the ship presents a smaller profile. Similarly, you'd want you own ships to also provide as small a target as possible, so both sides will end up aligning their ships to one another. Of course, it's entirely possible that one side will be inverted to the other. Who says we haven't seen this happen in TV or movies already? For all we know, Cardassian ships are always seen upside-down. I'ver never seen any deck plans for one that indicate otherwise. Remember, even the first time the model of the Enterprise was seen it was upside-down.

He Who Keeps This Stuff In Mind When He Designs His Stuff.

Scazzino
10-13-2006, 02:33 PM
I can see a reason for the 'up' direction

I'd think in a 3D battle, you'd really want to use the third dimension MUCH more, attacking from odd angles and directions... most of the space battle's I've seen in films & TV look more like sea battles with aircraft carriers and fighter planes...

I'd really expect ships to be at all sorts of angles, especially when approaching the enemies...

Stooch
10-13-2006, 02:37 PM
why bother attacking from all sorts of angles when your weapons have effective range of thousands of miles? all the current battles are extremely unrealistic because i feel that future space warfare would be much like long distance artillery exchanges or guided missle strikes from FAR away. like across a solar system or more.

I could see missles being hardwired to use the gravitational pulls from other stelar bodies to accelerate even harder and do primarily kinetic damage, afterall once the hull is pierced, the crew is done. no need to blow the ship up, you can and should be salvaging it anyway. missles would be slim and slender and actually - instead of slamming into a ship, maybe one would gently attach itself, tap the ship and drain the air out... and make sure you dont drain ALL the air out or the crew will explode and bleed all over the priceless klingon carpeting.

btw i think that future space artillery doesnt even have to be super high velocity, i think it would be electromagnetic rail based and project very thin, dense, metallic needles at a good speed but not too fast (so that you dont compromise the ships trajectory too much, forcing to waste fuel to compensate for recoil).

in fact the magnetic rail gun would be ideal since you can dial in exactly how much energy you need to expend. then the projectile will fly for days, maybe with a small vectoring engine to give little corrections during flight.

missles would be the deadliest weapon in space and probably the most effective. plus they have no recoil. lasers seem like a waste due to the extreme amount of energy for useable output.

and yes i know im a sick bastard :)

Scazzino
10-13-2006, 02:47 PM
why bother attacking from all sorts of angles when your weapons have effective range of thousands of miles?

Because that's the same idea (though larger scale) that led to the creation of "Top Gun"... The suits thought that with high tech long range missiles, dogfighting would be a thing of the past... they were wrong... and "Top Gun" was instituted to regain the upper hand for dogfights... ;)

Stooch
10-13-2006, 03:02 PM
true. but how can you dogfight something that is 500,000 miles away and is showering your base with death - to which you might be leashed to with fuel limitations.

also, if you think that space would have extreme maneuvering capability, i highly doubt it. Not over extended ranges, you would burn through your reserves in no time.

Also, lets say a projectile is to accelerate with a magnetic boost AND a short burn - high output motor. This beast gets up to insane speeds, by the time you even detect the tiny projectile its too late. the mass of your vehicle is simply too much for the kind of deflection you need, and a grazing hit is probably even more devastating. I would be spending all my money on shielding and ways to localize the damage instead of hoping for a top-gun :)

self sealing walls, reactive armor etc.

Scazzino
10-13-2006, 03:11 PM
Actually, they'd probably just push a button that did something nasty via long distance... like opening a black hole in your vicinity to suck you in... or just vaporize you by turning all your atoms into energy... but watching ships dogfight is probably more exciting for a movie or TV show... ;)

Stooch
10-13-2006, 03:19 PM
lol. true, but i think a dramatic 3d animation of long range battles could have merit. because strategy is now on a completely new level.

stealth is the new king. dont get seen - dont get shot!

you can hide behind suns, moons, planets, solar winds, asteroids, any anomalies. etc. you can aim at a ship on the other side of a system and is obstructed by planets by curving your projectile trajectory around planets. that is if you have ways of detecting it.

Our ability to use radar will be like a fart in the wind when you move up to space scale. it could actually be a very very exciting story with raids, sneak attacks, boarding. etc.

one possibility is all the fps games are hired by a new need for remotely controlled weapons or killing machines :) lol.

CMT
10-13-2006, 03:25 PM
true. but how can you dogfight something that is 500,000 miles away and is showering your base with death - to which you might be leashed to with fuel limitations.

In this case, I'd go with the patented electron tunneling quantum blaster which fires heavy projectiles faster than the speed of light to take care of the situation. That's what I'd do....if it were me :)

Stooch
10-13-2006, 03:26 PM
aim for the reactors! haha

starbase1
10-15-2006, 04:15 AM
The end of Larry Niven's 'protector' has an awesome realistic space 'battle' conducted at relatavistic speeds - it mainly consists of trying to get anything into the path of the other vehicle.

Nick

SplineGod
10-15-2006, 04:52 AM
Lasers and particle beam weapons would be very effective in space. They dont take nearly the power that people think and theres a large variety of ways to generate the power needed such as solar, nuclear and etc.

Missles and space ships generally need to pack as much hardware into as small a space as possible. This makes it even easier to hit a critical system. Lasers and particle beam weapons dont have an atmosphere to block them in space.

Boosting ships to high speeds takes a lot of energy over a period of time. The faster the ship is going the easier it is to do damage with low tech materials. Even the windows on the space shuttle have been damaged just from flecks of paint. You could basically pick up ships from a long distance away and just fling sand or pebbles and do severe damage. Shields may be possible but were talking about magnetic fields or something we havent thought of yet and magnetic fields can be easily defeated. Changing the trajectory of a ship at high speeds runs the risk of depleting your fuel.

There are ways to defeat lasers such as spinning the ship to distribute the energy, reflective skin, double skinned hulls with liquid in between etc. What works also depends on the type of laser being used and its possible to design a weapon system that uses multiple types of lasers in combination with particle beams. Its also possible to use XRay lasers to damage a ship or subject crews to intense radiation from a very long way away.

I think real space battles would be pretty boring and it would be rare to see a ship destroyed.

The laser thing is something Im familar with. Before getting into 3D thats what I did for a living. I worked on this project:
http://findarticles.com/p/articles/mi_m3820/is_n10_v26/ai_11621147

The USA has had chemical lasers in orbit where they could get off a few shots from high powered lasers by mixing chemicals to
generate a lot of power for a short period of time. Many of the space shuttle missions were used to refuel these systems. It was
determined that the shuttle could be vulnerable to attack and so we were told to determine if we could pump a laser using
neutrons directly from a nuclear reaction or IOR a laser powered by a small nuclear reactor.
Keep in mind this was back in 1989 - 1991 timeframe. I saw some pretty bizzare weapons systems that most would swear
was something out of science fiction. I can only imagine what they have now :)

Stooch
10-15-2006, 02:13 PM
I think that the best way to defeat a laser is by diffusion. have heat sensors that detect a laser and use countermeasures such as smoke canisters (in space you dont need a huge amount anyway, it will stick around too. Have a fine mist of highly reflective particles just reflect it in random directions.

And another thing about lasers, they destroy through heat and energy transfer, i would imagine that a simple piercing about an inch in diameter would deplete the atmosphere in seconds while preserving the integrity of the entire module. It is much easier to establish a thermal barrier rather then a kinetic barrier :) Energy in space is actually very precious. Its not easy to produce at all! Everything for space is designed to be energy conservative to the extreme.. you are talking about having a watt budget for everything!

Chemical systems also use ALOT of them, they require multiple trips just to replenish and IMO you would benefit more from using that for more critical supplies, like fuel or food or tools, personnel, etc.

I think the ideal gun in space is something extremely light weight, extremely portable, self contained and does not require constant management, maintenance and resupply.

So what i envision is an electronically articulated - external weapons system. That would use a small servo motor to make precise movements. it would be made out of lightweight, ballistic grade plastics. The barrel would be as long as possible to maximise the impulse from the small propellant charges. It would be designed to contain all ammo internally and specced to last only the life of that ammo reserve. It would have an effective means to reuse the spent propellant to dampen the recoil and mitigate the shock of the gun. the idea is to prevent the firing platform from drifting and to account any drift into firing solution :)

Magnetic acceleration is also a useful solution but may be relegated to "fling" debris in the path of a ship, or having a large capacitor array - powered by excess current for a more powerful shot. I could imagine that the savings of not having to carry the weight of the ammo propellant might be applied directly to boost energy production. even though a nuclear reactor will be installed on spacecraft. they do not guarantee an abundance of power. Any nuclear reactor would be for long term power output rather then maximum. One simple reason is that radiation levels would be harder to manage with a more intense reaction and you want to keep the reactor going for as long as possible! Im sure that you wouldnt want to refuel the nuclear reactor on-board... so if it can last 1000 years and be modular - then cool...

btw one good way to recycle space debris is to compact it on-board and produce more shot for the gun..

Bog
10-15-2006, 02:31 PM
Righto chaps, if you're after Sci Fi With Realistic Space Battles, then please go here:

http://www.baen.com/library/

Navigate to "David Weber" in the Authors section, and download "On Basilisk Station". It's free, and legal, and that nice Jim Baen (rest his soul) wanted these to be given away free so help yourselves. The Honor Harrington series (aside from being a thumping good sci-fi rendition of the Hornblower Saga amongst other things) has got absolutely realistic space battles. Proper relativistic stuff, given an FTL and gravitic drive tech-base. If you like your sci-fi as hard as neutronium... give it a go. The second book in the series (The Honor of the Queen) is also free, but all of Weber's stuff is worth a whirl.

And it would never, ever make an interesting movie, because engagements fought from 20 light-seconds apart just ain't so much fun to look at.

Stooch
10-15-2006, 02:47 PM
lol true. but it would make for some good drama...

gerry_g
10-15-2006, 03:35 PM
Since when did reality take precedent over our perception of reality, give me a crossable right way up universe filled with magical ambient light any day, at least rocket exhaust plums don't rise on warm thermals and the models wobble on their strings anymore the way that did in the old Flash Gordon days........

Stooch
10-15-2006, 04:35 PM
Righto chaps, if you're after Sci Fi With Realistic Space Battles, then please go here:

http://www.baen.com/library/

Navigate to "David Weber" in the Authors section


im reading one of the books you mentioned. I find it funny how the conflict centers on fanatic religion with bad guy ship names such as mohammed, karl marx, etc and how these evil aliens almost have a muslim flavor to them...the book title is crusade....

kinda lame but im still giving the books a shot heh.

SplineGod
10-15-2006, 06:25 PM
There are ways that ppl have used to try and defeat lasers. How well laser radiation is absorbed or dispersed can depend on the amount of energy in the beam as well as the wavelengths involved.
XRay lasers have a lot of pentrating power and rather then burn thru the skin of a missle it causes outer layers of skin to explose which causes the inner layer to explode the opposite direction which pretty much shreds anything inside. Reasearch has been way for years to also develop gamma ray and cosmic ray lasers. I remember years ago there was talk about using gamma ry lasers to literally transmutate the plutonium in a warhead to another element renderning the warhead inert.

A group next to mine had figured out a way to defeat thermal blooming (the gas that the laser or particle beam would go thru would get heated up ahead of the beam and refract the beam like a lens). They determined that the major gas responsible for the effect was monotomic oxygen. So they built a laser that output a beam in the UV region at the resonant frequency of the monotomic oxygen. This would ionize the gas and provide a pathway for the particle beam to follow. Think of it as a giant Tazer. :)

Another proposal that was happening was to fire projectiles of plutonium or U235/U238 and very high velocities. The projectiles themselves wouldnt do a great deal of damage but they proposed to fire a beam of neutrons just before the projectile would impact and cause it to fission creating an atomic blast very near the target. :)

T-Light
10-15-2006, 07:09 PM
Splinegod -

The projectiles themselves wouldnt do a great deal of damage but they proposed to fire a beam of neutrons just before the projectile would impact and cause it to fission creating an atomic blast very near the target :).
How on Earth can you write a sentence like that and end it on a smiley? :D

Dave Jerrard
10-15-2006, 07:54 PM
Splinegod -

How on Earth can you write a sentence like that and end it on a smiley? :DHe wasn't the target?


He Who Needs To Read Some More Niven Again.

SplineGod
10-15-2006, 09:14 PM
Splinegod -

How on Earth can you write a sentence like that and end it on a smiley? :D

It was a bit surreal working at Sandia sometimes. These guys would sit around and discuss weapon systems that could do this in much the same we we discuss LW. :)

Stooch
10-15-2006, 10:46 PM
:thumbsup: good stuff. keep it coming lol. the most brilliant minds also happen to be the most twisted :)

also, i think that magnetic fields dont really make sense for stopping projectiles and explosions and stuff. But ionized radiation or xrays are actually quite effectively stopped by electromagnetism, hence solar winds and space radiation arent killing us all as we speak ;)

I think that projectiles are still the most dangerous item to prevent, i can see lasers being used against those primarily.

also, i dont think a laser would be affected by electromagnetic shields since sunlight seems to get through just fine but if you suspend a few tons of magnetized reflective dust, you could potentially use magnetic fields to concentrate them between the laser source and the ship. i would imagine that with a sufficiently deep layer, lasers would become ineffective.



There are ways that ppl have used to try and defeat lasers. How well laser radiation is absorbed or dispersed can depend on the amount of energy in the beam as well as the wavelengths involved.
XRay lasers have a lot of pentrating power and rather then burn thru the skin of a missle it causes outer layers of skin to explose which causes the inner layer to explode the opposite direction which pretty much shreds anything inside. Reasearch has been way for years to also develop gamma ray and cosmic ray lasers. I remember years ago there was talk about using gamma ry lasers to literally transmutate the plutonium in a warhead to another element renderning the warhead inert.

A group next to mine had figured out a way to defeat thermal blooming (the gas that the laser or particle beam would go thru would get heated up ahead of the beam and refract the beam like a lens). They determined that the major gas responsible for the effect was monotomic oxygen. So they built a laser that output a beam in the UV region at the resonant frequency of the monotomic oxygen. This would ionize the gas and provide a pathway for the particle beam to follow. Think of it as a giant Tazer. :)

Another proposal that was happening was to fire projectiles of plutonium or U235/U238 and very high velocities. The projectiles themselves wouldnt do a great deal of damage but they proposed to fire a beam of neutrons just before the projectile would impact and cause it to fission creating an atomic blast very near the target. :)

SplineGod
10-15-2006, 11:47 PM
The most interesting thing I had seen was back in 1990 or so. What I was shown had already been deployed for about 10 yrs already which pretty much shocked me. I was told it was an antiterrorist weapon that Delta Force was using.
Essentially it was a very short tank, kind of long and wide with only a bubble like turret on top. The tank contained a closed loop filled with C02 gas that was circulated at supersonic speed using a jet engine. A section of the tube would narrow down into a venturi where the gas would go hypersonic. Just past the venturi was a section with air foils in it. When the C02 would strike that the carbon and oxygen would temporarily dissociate and then recombine. When they did they would emit a particular frequency of Infrared radiation that was amplified and would be emitted thru a zinc selenide window.
The turret had focusing/aiming optics and a LIDAR range finder.

This tank would be deployed from a C-130 or other transport and guided to the ground using a parasail. A soldier with a laser designator would indicate a target which the tank would pick up. When the tank fired it would first determine the range of the building via LIDAR, the optics would focus and then beam would be fired. Instead of genrating a collimated beam of light it would focus the beam inside the building. The energy density would be so high that the air would ionize and it would create an extremely high temperature plasma that would explode and vaporize everything within a certain range leaving no trace of how it was done.

I was also shown a miniaturized version of this that was worn as a backpack that had thick fiber optic cable that went to a rifle like assembly. It was apparently a sniper weapon. :)

Verlon
10-16-2006, 12:07 AM
Well I work with a lot of laser equipped tools, and I am here to tell you that the things are not all that reliable. There is a LOT to be said for pulling the trigger and having the weapon actually function. The chemical powered cartridge shooting a mass at the enemy is quite functional...more so in space than on earth (no atmosphere and not much gravity to mess things up). Lasers are also inefficient with energy. I am not saying they are useless, just that they have many weaknesses.

Cheap to make, and you can fire even if the main reactor is down.

The space battle are becomes less dangerous in seconds as the shrapnel and spent rounds fly off into space. The density of these particles would be decreasing exponetially over time (and all the ships would have to have SOME protection from micro-meteorites and other debris anyway--running into a rock at 1000 kph would be like getting hit by a bullet doing the same speed).

Firing a bullet from 1000 miles away would be useless. If your target changes course even slightly, you miss by miles. Counting on them being committed to a specific course doesn't pan out either. Given rates of acceleration, we have to conclude that either a) all the beings in the show are superhuman and can sustain inertial changes that would kill many comic book characters or b) they have some way of cheating inertia.

Much of this depends on where technology is when the people develop FTL drive. If some scientist discovers "hyperdrive" tomorrow, do you think we will wait until we develop energy weapons to explore space?


If a ship uses chemical fuel (like a rocket), it can still create the traditional fiery explosion since that fuel must also carry its oxygen source with it.

The rules in sci-fi can be ratioanlized based on what technology is made available...and the science in science fiction is no worse than the science in the rest of TV:

A full gas tank is in no danger of exploding, even when shot
A bullet in the shoulder takes more than a week to recover from
CSI guys are rarely, if ever, the arresting officers in major cities
A large percentage of police cases go unsolved
A fair percentage of prosecutions resolve in favor of the defendant
Not all christians are zealots **** bent on recreating the spanish inquisition
Not all catholic priests are secretly on to some satanic plot to end the world
Death is normally permanent
Sports cars (real ones) are faster than mini-vans.
Diamonds are a LOUSY way to move money around because their resale value is utter crap.
Its not very hard to talk to an airplane on the radio.
Men are generally physically stronger than women.
Some people use passwords that are REALLY hard to guess.
And this is just off the top of my head...

The picture of Saturn is very cool. :)

Ratboy
10-16-2006, 10:49 AM
Firing a bullet from 1000 miles away would be useless. If your target changes course even slightly, you miss by miles. Counting on them being committed to a specific course doesn't pan out either.Actually, it's not that useless. Fire the bullet, and the target has a choice: dodge or take the hit. Fire enough bullets in the right spread and you can "encourage" the target ship to dodge in the direction you want them to go.

They may not be the most effective weapons, but they'd be great maneuver constraints.

starbase1
10-16-2006, 11:52 AM
Actually, it's not that useless. Fire the bullet, and the target has a choice: dodge or take the hit. Fire enough bullets in the right spread and you can "encourage" the target ship to dodge in the direction you want them to go.

They may not be the most effective weapons, but they'd be great maneuver constraints.

And if you are travelling at 90% of light speed, it will be staggeringly expensive in ful terms to make the tinestest course change - darting around in an evasive pattern is not an option!

Verlon
10-16-2006, 03:04 PM
And if you are travelling at 90% of light speed, it will be staggeringly expensive in ful terms to make the tinestest course change - darting around in an evasive pattern is not an option!

Only if your vessel has mass...

See the bit about cheating inertia. Assuming the ship can accelerate to relatavistic speeds in seconds without crushing the crew so fast they skip jelley and all become quantum black holes (with a tip of the hat to Niven), then they MUST have a way of cheating inertia. Suddenly, darting around looks possible.

At 90% of the speed of light, the bullets won't be in the neighborhood long.....not sure how much course correction you would get... Space is still very vast