Shrugger! Unity!

[Draco18s]

Is there a difference in technological difficulty in detecting radiation of different wavelengths of the electromagnetic spectrum?
And if so, what is necessary to make it work?

YES.

Certain wave lengths--like x-rays--will pass right through ordinary mater and not bounce unless you use very very slight alterations in its direction.

Sometimes other challenges.

http://en.wikipedia.org/wiki/X-ray_telescope

[Shrugging Khan]

It recently occurred to me that perhaps I did not need to write price lists and functionality for detection equipment meant for the entire EM spectrum, after all.

Aside from visible light and infrared, what else would even be relevant in a space setting with present-day technology? Radiation from shipboard/orbital nuclear power plants maybe (whatever wavelength that may have)? What else comes to mind?

[Draco18s]

X-Ray.

[Shrugging Khan]

You seem unhealthily infatuated with X-Rays. Care to give me a hint as to the tactical or strategic significance of X-Rays?

[Draco18s]

You seem unhealthily infatuated with X-Rays. Care to give me a hint as to the tactical or strategic significance of X-Rays?

Honestly no idea
I just know that x-ray telescopes exist and that they're damn hard to focus.  Too sharp of a reflection angle and they just pass right through.

(This is why you have to hold a stupid plastic thing in your mouth when the dentist x-rays your teeth: they don't bother reflecting at all: you're actually biting down on the film!  Or detector, if they've modernized)

[keith.lamothe]

I think X-rays are also the operative band for "bomb-pumped lasers" (when the bomb in question is fission or fusion), a possibly effective way to use energy weapons when you're not close enough to use ones mounted on your ship, and without the difficulty of actually physically striking the enemy ship with a projectile at distances where you don't even have a real-time fix on their location from shipboard sensors.

But you wouldn't really need detection gear for X-rays in that case.  If they hit, you'll know it.

[Shrugging Khan]

@ Draco :  Well, one thing your links made clear is that I will make X-Ray detection equipment (and such working at similar wavelengths) especially costly to include on a ship 

I think X-rays are also the operative band for "bomb-pumped lasers" (when the bomb in question is fission or fusion), a possibly effective way to use energy weapons when you're not close enough to use ones mounted on your ship, and without the difficulty of actually physically striking the enemy ship with a projectile at distances where you don't even have a real-time fix on their location from shipboard sensors.

But you wouldn't really need detection gear for X-rays in that case.  If they hit, you'll know it.

But what if they just hit the next ship in the fleet? Then you'd have to look out for follow-up shots so you can make out where they're firing from!

Alright, so we have Infrared, visible, X-Ray...Radio waves, obviously!
What other wavelengths would be used in weaponised lasers?

And one older question still stands - guess I'll have to do some research - what kind of radiation would nuclear drives or NPPs emit?

[Draco18s]

What other wavelengths would be used in weaponised lasers?

Radio, heck even visible light, is a shitty wavelength for weaponizing.  Too low energy.  Visible light has a habit of scattering and diffusing rapidly when it hits dust.  Radio waves are so low energy that they can't actually interact with matter in a noticeable way.

And one older question still stands - guess I'll have to do some research - what kind of radiation would nuclear drives or NPPs emit?

Very high energy.  Gamma, alpha, and beta are the most common.  Alpha and beta are harmless (stopped by a sheet of paper and 1/4 inch plywood, respectively) where as gamma will hug.  You.  Up.

Gamma rays typically have frequencies above 10 exahertz (or >1019 Hz), and therefore have energies above 100 keV and wavelengths less than 10 picometers (less than the diameter of an atom)

For a point of reference, red light is...670 nanometers if I remember correctly.  Yeah.  All the way down to violet at 400 nm.  So picometers worth of wavelength is orders of magnitude more energetic.

Generally speaking when gamma rays interact with matter they cause the excitation of electrons, which then radiate off as another frequency of light (and strip the atom of the electron itself).  [/not science; based on an understanding of wikipedia]

[Shrugging Khan]

Ouch...guess I made myself sound like an idiot. I didn't mean to say that I was going to have waponised lasers based on radio or visible light, just that detection equipment for these wavelengths would be in the game 

Gamma radiation...check!

[mrhanman]

Don't forget microwaves.  Often used for communication and the heating of hot pockets.

[keith.lamothe]

And there are certainly sci-fi races to which "battleship full of human crew members" and "hot pocket" are, for all truly important purposes, equivalent.

[Draco18s]

* Draco18s laughs

[Shrugging Khan]

I'm trying to find a smart solution for the following problem:

Several spacecraft are moving at various velocities, possibly accelerating constantly or at random intervals. The captain of one of the ships has, for reasons unknown, decided to ram another one - or at least navigate close enough for a friendly waving of hands.

Now, our Capitan faces the first problem - he needs to point his craft at the next vessel over, using his modest RCS - as quickly as possible. So he goes and fires it continuously at full power. While doing so, he tries to determine at which point he will need to fire it in the other direction in order to cancel the rotation.

What formula would you use to calculate whether that point has been reached?

[Draco18s]

I would hand you a very complicated looking sliding-wheel device (like a decoder ring) if I had it, but I don't.

My math teacher in high school had it though, and it was used to figure out how to rotate an object with thruster jets, just as you describe.

[Shrugging Khan]

Any idea where I could find one; ideally in digital form? 

Edit: Complete with the formulas and all, preferably.