Is there ligntning in space?

RiderOnTheStorm

hi. sorry to ask, if this has been discussed before, but the search facility is not what it used to be.

Can you get lightning in space?

I ask because I am writing a S/F novel, and the hero has to defend a space-station against an alien ship that is attacking. He launches his own attack, using laser / plasma rifle, and some crude (but powerfull) mines. In the story I want the alien craft to quickly disperse the energy through wires / cunduits / canals in the surface of the ship. This would lessen the force of the energy on the point of impact (by diluting it all over the surface). But the hero launches such a forcefull attack that the craft glows like a lava flow, and I wanted to add lightning strikes coming from the craft (as the alien is releasing the energy accumulating on the hull).

So, can you get lightning if there is no 'earth' for the energy to follow or flow to? There is the highly charged alien craft, a space station (1 mile apart?) and a lot of floating debris............

any and all help is most welcome!

miles teg

RiderOnTheStorm wrote:

...
any and all help is most welcome!

I can't help at from a scientific point of view, but given you're writing a science fiction novel, does it need to be 100% scientifically accurate?
Why not just write what you'd like to write? Sure, some our fundemental laws of physics are in question if a particular Irish company is to be believed

RiderOnTheStorm

miles teg wrote:

Sure, some our fundemental laws of physics are in question if a particular Irish company is to be believed

lol... i was just looking at that. My physics only goes up to leaving-cert (many years ago, so lots forgotten!) but it seems a bit simple to me! Also, where do they get the magnets from? surely lots of energy goes into making / maintaining a magnet, and then claiming to get energy out of a magnet using the magnets own force is just robbing Peter to pay Paul?

but back onto this post.....
yes, its a work of fiction, so I can really say anything I want. But I want to give the reader a reason, a willing suspension of belief. (also thinking of the Syrania post, where kid gets electrocuted in swimming pool... that got a few posts!) I dont want to make outlandish claims and present them as believable fact. But the point is taken, and thanks for the reply.

Spear

RiderOnTheStorm wrote:

hi. sorry to ask, if this has been discussed before, but the search facility is not what it used to be.

Can you get lightning in space?


So, can you get lightning if there is no 'earth' for the energy to follow or flow to? There is the highly charged alien craft, a space station (1 mile apart?) and a lot of floating debris............

any and all help is most welcome!

http://jtintle.wordpress.com/2006/05/16/europa-caught-in-the-middle/

Seems you can.

ApeXaviour

RiderOnTheStorm wrote:

So, can you get lightning if there is no 'earth' for the energy to follow or flow to? There is the highly charged alien craft, a space station (1 mile apart?) and a lot of floating debris............

Lightning comes as a result of electrostatic discharge between two areas/objects of different potential. Since there is sheet lightning etc. (between different areas of clouds) then there is no need for an earth for this to occur.

However... Lightning as we know it, is air becoming rapidly heated and turning into a plasma which illuminates and causes acoustic shockwaves due to its rapid expansion. Since space is a relatively high vacuum I cannot see this occuring in the same manner.

But electrons can move through a vacuum easily enough (eg cathode ray tube). And accelerating electrons apparently emit radiation no? I'm a little sketchy on what you would actually see, if anything at all. Maybe some else can explain this part a bit better? I just know it wouldn't be lightning as we know it in the absence of a certain density of gas.

Also energy release in the form of lightning couldn't occur without a difference in potentials. Unless these weapons caused a signficant charge on the alien ship the energy wouldnt dissipate like this. If it's glowing red, it's hot. So the heat energy would likely dissipate via radiation (hence the glowing red). Maybe conduction if it's touching something. Or even a physical/chemical change i.e. the hull melting or chemically reacting.

Good luck with your book!

RiderOnTheStorm

thx guys. all appreciated.

forgot about sheet lightning. if the differential between 2 (un earthed) objs is high enough, you will get a discharge (eeeuw, gross!)....should apply in vacuum too. point taken about crt and visability. As long as I am not completly contradicting well known laws, I will be happy and fudge the rest. . . . . . . I have seen the CSI thread here! I dont want to be lambasted like that for some basic flaw. Then again..................
Q:Whats worse than pople talking about you?
A: People not talking about you!

(GBS? or Oscar Wilde?)

PS love the sig ApeX!

Capt'n Midnight

you can't see electricity in a vacuum , you can only see the light from the atoms

don't forget that all the debris and stuff from the explosions will be around too so you will have plenty of atoms to be ionised,

ionised atoms can of course be easily deflected with a magnetic field , just like the earths one protects us from the solar wind. few of the atoms you have floating around would be in their ground state ( maybe ) so almost all could be moved by said magnet field ,

I suspect you are writing a space opera rather than hard sci fi, mines and projectile weapons would be far less useful than lasers, assuming that any alien that made it here would be able to use 0.01% of the energy the need to power their craft on interstellar journey into the laser device ( it could just be gas between mirrors with a surge of energy into it) Unless they use a generation ship like we do or have very low technology because they inherited bits from another race.

Professor_Fink

Capt'n Midnight wrote:

you can't see electricity in a vacuum , you can only see the light from the atoms

Actually all accelerating charged particles emit electromagnetic radiation, so there are circumstances under which you could see it.

Professor_Fink

Capt'n Midnight wrote:

I suspect you are writing a space opera rather than hard sci fi, mines and projectile weapons would be far less useful than lasers, assuming that any alien that made it here would be able to use 0.01% of the energy the need to power their craft on interstellar journey into the laser device ( it could just be gas between mirrors with a surge of energy into it) Unless they use a generation ship like we do or have very low technology because they inherited bits from another race.

Actually, I can't see a problem with missiles, other than the fact that you'd eventually run out. I would think a laser is actually easier to protect against.

Capt'n Midnight

Professor_Fink wrote:

Actually all accelerating charged particles emit electromagnetic radiation, so there are circumstances under which you could see it.

granted, but there are very very few particles in a vacuum

Professor_Fink wrote:

Actually, I can't see a problem with missiles, other than the fact that you'd eventually run out. I would think a laser is actually easier to protect against.

only if you had perfect mirrors, the laser device could use wavelength dimension coatings to achieve this but simply using several different colour lasers in succession should burn off any such protective coating on the space station.

A laser will cover 150,000,000 km in 8.5 minutes and you can't see it unless it hits something. Missiles are a little slower and easier to detect. The star wars programs in the US have to work through the atmosphere ( minimum density 10 tonnes per m2 , far worse at an angle ) and have destroyed missiles using small amounts of power compared to that the aliens would probably have.

very close in missiles would probably be better, but don't forget that with suitable mirrors lasers could be targeted extremely fast


Or you could "fire delta beams"

Professor_Fink

Capt'n Midnight wrote:

granted, but there are very very few particles in a vacuum

Actually I was refering to particles torn of the surface by the potential. There don't have to be any particles in the intervening space.

Capt'n Midnight wrote:

only if you had perfect mirrors, the laser device could use wavelength dimension coatings to achieve this but simply using several different colour lasers in succession should burn off any such protective coating on the space station.

Or you could just refract the light back off the ship.

Capt'n Midnight wrote:

A laser will cover 150,000,000 km in 8.5 minutes and you can't see it unless it hits something. Missiles are a little slower and easier to detect. The star wars programs in the US have to work through the atmosphere ( minimum density 10 tonnes per m2 , far worse at an angle ) and have destroyed missiles using small amounts of power compared to that the aliens would probably have.

I can't see speed as being all that much of an issue, since the aliens are presumably arbitrarily advanced, and so could propel a missile arbitrarily close to the speed of light. Chances are that you could deliver substantially more energy to the target that way. Also, I have no idea what you mean by " ( minimum density 10 tonnes per m2 , far worse at an angle ) " since you aren't using units of density. If you mean 10 tones per m^3, then you are simply wrong (water is 1). If you mean across the some distance, then you need to include that info.

My only point here is that it could easily be hard sci-fi without having to rely on lasers. Actually, messing someone up with GR would be far more impressive ;-)

ApeXaviour

Professor_Fink wrote:

Also, I have no idea what you mean by " ( minimum density 10 tonnes per m2 , far worse at an angle ) " since you aren't using units of density. If you mean 10 tones per m^3, then you are simply wrong (water is 1).

Considering the context, I'd he's talking about optical opacity which is in those units. It would be of that order of magnitude for our atmosphere and makes sense when talking about lasers.

That'd be a form of density too no? Like the way surface charge density is.

Professor_Fink

I don't know. I was thinking that he meant the actually meant density as in mass per unit volume.

Surface charge density is called a density because you are restricted to a 2D space, and the units of volume for such a space are m^2.

Anyway, the reason I brought it up is because I can't work out for sure exactly what he means from context. It was tangential to the discussion anyway.

RiderOnTheStorm

wow, thanks for all the thought and effort, guys. Much appreciated.

I had thought that the alien craft would be at approx same technology level as 'us' ... but just different (ie alien). In the story, it is mans first contact with intelligent alien lifeforms. The ship will be able to absorb and reflect / deflect energy (eg lasers / plasma / ion weapons). The hero will use mines disguised as space-flotsam (.... or jetsum? will have to look that up) so point about detecting / countering missiles will not come up.

For reasons that will become aparent later in the story, the alien craft does not take hostile counter-measures when attacked.

The story is somewhere between space opera and hard s/f. The reason that mines are being used is due to necessity rather than design. The space station is non-military and no aliens have ever been discovered in the hundreds of years of exploration (date of story is about 25th C) so our hero has to improvise when he is contfronted with hostile alien craft.

oh.... not sure if its a physics thing....but alien is very dog-like and to underline that, I have made the warning systems on his craft all scent based. No flashing lights or klaxons, but different smells to indicate different problems. Its not important to the story, just a way of showing how aliens may have developed differently.

Professor_Fink

RiderOnTheStorm wrote:

oh.... not sure if its a physics thing....but alien is very dog-like and to underline that, I have made the warning systems on his craft all scent based. No flashing lights or klaxons, but different smells to indicate different problems. Its not important to the story, just a way of showing how aliens may have developed differently.

There is a problem with this: The scents will linger, unless there is some way to quickly exchange all the gas in the room. So if you use it to give various warnings, it would become very hard to determining what happens when, since some scents may take longer to reach the nose than others, etc, due to the movement of air (or whatever they breath).

Visual warnings will always be fastest, but you may need something like sound to attract attention to it (if for example people are likely to be asleep, looking the wrong direction, etc.).

Capt'n Midnight

Professor_Fink wrote:

Actually I was refering to particles torn of the surface by the potential. There don't have to be any particles in the intervening space.

my aliens started shooting from far further away

Professor_Fink wrote:

Or you could just refract the light back off the ship.

my aliens have these fancy UV lasers

Professor_Fink wrote:

Also, I have no idea what you mean by " ( minimum density 10 tonnes per m2 , far worse at an angle ) " since you aren't using units of density. If you mean 10 tones per m^3, then you are simply wrong (water is 1). If you mean across the some distance, then you need to include that info.

the distance would be the atmosphere, density would be the worng word, a laser beem from the ground has to go through as much matter as if 10m under the water ( different adsorbtion though )

Professor_Fink wrote:

My only point here is that it could easily be hard sci-fi without having to rely on lasers. Actually, messing someone up with GR would be far more impressive ;-)

but what sbout the special effects and ZZZISSSTTTT noises they make ?
ok I'll drop the lasers, but the delta beams stay

sgtdiesalot

Professor_Fink wrote:

There is a problem with this: The scents will linger, unless there is some way to quickly exchange all the gas in the room. So if you use it to give various warnings, it would become very hard to determining what happens when, since some scents may take longer to reach the nose than others, etc, due to the movement of air (or whatever they breath).

Visual warnings will always be fastest, but you may need something like sound to attract attention to it (if for example people are likely to be asleep, looking the wrong direction, etc.).

only problem with visual warnings is that while they would get the dogs attention, coloured warning would be no good as dogs are colour blind, but then a visual warning to get attenion with a verbal warning would work

RiderOnTheStorm

like i said, its not integeral to the story. i just wanted to introduce something that shows that the alien is really alien, ie has different set of prioritised senses. As humans we cant see past using sight as primary sense, and i wanted also for the reader to imagine what it might be like to 'see' with your nose. What is it like for my pet dog to sniff the air and 'see' scents in fields like as if they were glowing lines to my eyes?

Scent has some advantages over sight / sound, like it works when you are asleep, it will travel around corners, several scents can be processed in one sniff (just think about wine tasters getting 'hint of farmyard, oak, blueberries, leather, roses, vanilla, etc from one sip!) I imagine a dog can tell the age of a scent and differentiate between and older warning and a newer warning, if they were both in the air at the same time. But I take the point about scrubbing the air. I imagine all space craft would have to have air cleaning / conditioning / re-cycling units. I will incorporate it into the story, and I will make sure that scents are backed up with sound warnings too. There will be lights of course, but they will play less of a role in warning / status systems due to poor light receptors of dogs.

Thx again for all the thoughts and suggestions. I will keep you posted about the progress of the novel.......but dont hold your breath!

ressem

These electrostatic 'space vampires' of interest to you? To be seen at an international space station near you.
http://www.newscientistspace.com/article/dn9669

RiderOnTheStorm

lol....space vampires.... love it! ta v much!