Battles within the gas giant

[aramis]

I didn't know about all those sensors, but are they active or passive? I guess the yare active, as radar is active and sonar uses to be unless you try to detect a sound emiter, and I guess this is not the case for Ground Penetrating Sonar.

Current gravitometers are extremely passive.
GPR and GP Sonar are active.

 

[aramis]

Probably I'm outdated about ASW sensors, but the closest thing I remember in Harpoon was the MAD, which detected magnetic, not gravitational, anomalies, and had problems with non-ferrous (and so non magnetic) items and with non moving ones...

The current gravitometers can't detect subs in water very well - the sub is well below threshold. They're used mostly to detect lava movement.

 

[Greylond]

Probably I'm outdated about ASW sensors, but the closest thing I remember in Harpoon was the MAD, which detected magnetic, not gravitational, anomalies, and had problems with non-ferrous (and so non magnetic) items and with non moving ones...

Yea, MAD sensor is Magnetic. Also, they drop sonabouys that use passive and active sonar. Which is akin to what I was going to suggest;

Remote/Robotic sensor probes dotted in a pattern covering the outskirts of the system. Have them set to transmit a tight beam to a communications relay, again robotic/computer controlled. And your Scout ship make random sweeps to for maintenance checkups and replace as needed.

 

[Travellerspud]

there will be a signal-to-noise ratio cut-off with any sensors, passive or active. What is the relative level of signal for a starship engine vs. the "rms" level of the gas giant? depending on the detector resolution, usable s/n ranges typically are 40-150dB....I do not know either signal level, but at some point the gas giant levels would mask the ship's. The only question is wether or not this exceeds the crush depth of the hull...

 

[Dragoner]

http://science.nasa.gov/science-news/science-at-nasa/2004/20feb_radiostorms/


What effect would the radio storms have on sensors?

 

[Piper]

Most search and tracking radars operate in the 1 to 10GHz range. Radio storms seem to be confined to frequencies less than 100MHz. They shouldn't have any noticeable effect at all.

Absorption bands are another story.

http://en.wikipedia.org/wiki/Radar#Frequency_bands

There might be areas within a gas giant atmosphere that are opaque to certain radar frequencies. If there are, changing to a different frequency unit should fix that problem.

 

[Dragoner]

My next question would then be: is that freq range peculiar to Jupiter or could other GG's have different frequency ranges?

 

[aramis]

Most search and tracking radars operate in the 1 to 10GHz range. Radio storms seem to be confined to frequencies less than 100MHz. They shouldn't have any noticeable effect at all.

Absorption bands are another story.

http://en.wikipedia.org/wiki/Radar#Frequency_bands

There might be areas within a gas giant atmosphere that are opaque to certain radar frequencies. If there are, changing to a different frequency unit should fix that problem.

many current systems are multi-band. Traveller ones are likely multi-band systems, too.

 

[Omnivore]

many current systems are multi-band. Traveller ones are likely multi-band systems, too.

I'd expect them to be not only multi-band but frequency agile. For military systems at least, this largely defeats most ECM as well as making absorption bands a non issue since the frequency varies very rapidly in a pseudo random pattern.

 

[aramis]

I'd expect them to be not only multi-band but frequency agile. For military systems at least, this largely defeats most ECM as well as making absorption bands a non issue since the frequency varies very rapidly in a pseudo random pattern.

It reduces the effects of absorption bands, but doesn't eliminate them entirely.

Absorption bands also, if hit strongly enough, reradiate in other frequencies. Radar units, especially longer ranged ones, are particularly powerful radio sources.

 

[Piper]

My next question would then be: is that freq range peculiar to Jupiter or could other GG's have different frequency ranges?

Revised information on Jupiter:

http://en.wikipedia.org/wiki/Decimetric_radio_emissions#Jupiter_as_a_pulsar

Jupiter regularly emits at a much higher frequency range than was implied in the NASA image I referenced earlier. My bad for not checking deeper into that.

I'm not really qualified to interpret this data but, as an educated guess, I would imagine that this would show up as interference or static to your radar. Unfortunately for the hiding SDB's, interference like this is easily filtered out.

The more powerful, periodic microwave bursts might (wild guess here) provide enough raw energy to interfere with radar. Thing is, they are periodic and even if they did interfere with sensors, you could easily time your operation to avoid most of it. I hope someone with a better understanding of what's involved can clarify this.

At some point, you run into the reality-vs-romance wall. Personally, I like the idea of ghostly defenders rising through the murk to swap shots with an invading force struggling to refuel. If the science doesn't support it, so be it. If I wanted my sci-fi that hard I'd play Attack Vector: Tactical.

http://www.adastragames.com/products/adastra/av.html

 

[whartung]

[*]Assuming both parties are close enough to trade beam fire, they're fighting in Striker-style air combat. They're running on 30-second turns, firing twice per turn; they may evade under Striker rules, gaining the agility defensive bonus.

[*]Spinal mounts are not available for in-atmosphere ship-to-ship combat: particle accelerators are out in the first place, and there's no way atmospheric buffeting is going to permit anything remotely like enough accuracy to manage a spinal meson shot against an evading target less than 40 Km off. Meson bays are available.

We have, today, the M1 tank, with a stabilized gun, computers, and sensors (lasers among other things), that can hurl a big, heavy, slow projectiles while moving, over terrain, and hit its target several kilometers away, over 90% of the time -- at night.

I know what the rules say, but there is no "evading" a light speed weapon at 40km. At 40km, a target flying at 1200MPH (Mach 2ish) moves 7cm before the weapon hits. The computer simply needs to figure out "where will the target be in 13/100,000ths of a second" to aim the gun mount. Not much time cognitively, lots of time for a computer.

An F-15 takes up roughly 0.0278 deg of "sky" at 40km. Which is to say, not a whole lot. An Azhanti High Lightning takes up 0.00005 deg of sky (a lot, lot less) at 300,000km (1 light second), which is well within range of many ship-to-ship weapons (not just spinals). Spinal weapon clearly have some ability to "tune" their attack when the weapon is "in arc" (which admittedly is limited), it's not just pointing the ship until the big + painted on the bridge window lines up with the target and the Captain slaps the big red FIRE button on his command chair. Also, Meson guns fall under the "close only counts for horseshoes, hand grenades, and atom bombs...and meson guns". So, it may well be limited, but there is definitely danger space in front of a spinal mount, even at close quarters.

So, through high tech gizmology and Imperial Science, ship weapons have truly staggering resolution. Once the gun mount locks on and tracks you, even for a second, you're toast. It's fair to argue that agility may affect the ability to gain lock, but frankly it's more a sensor task than anything else. Or it's a mount task (slow mounts more affected than fast mounts, but mostly in terms of how fast the gun can track). Again, at 1200MPH, at 40km, it's moving about .75 deg/sec. That's not very fast. Get closer and it gets more interesting, but far away? Turkey shoot.

 

[McPerth]

At some point, you run into the reality-vs-romance wall. Personally, I like the idea of ghostly defenders rising through the murk to swap shots with an invading force struggling to refuel. If the science doesn't support it, so be it.

I guess that's also my view, and I don't like the idea of nearly unfalible sensors against whom there's not defense nor way of hiding.

I understand the fact that there's no stealth in space, but I'm harder to accept tht there might not be stealth in a GG atmosphere (while the fact that there can be SDBs hidden and lurking there is ever present in Traveller).

 

[whartung]

I guess that's also my view, and I don't like the idea of nearly unfalible sensors against whom there's not defense nor way of hiding.

I understand the fact that there's no stealth in space, but I'm harder to accept tht there might not be stealth in a GG atmosphere (while the fact taht there can be SDBs hidden and lurking there is ever present in Traveller).

I agree with this. The physics ruins a lot of the romance. From space battles that are brutally short and lethal, starting hundred year wildfires because the fusion cone of your drive ignited that quiet mountain meadow and surrounding forest that you wanted to land in, to the fact that we may not have access to unlimited, ubiquitous "free" energy ( http://physics.ucsd.edu/do-the-math/2011/07/galactic-scale-energy/ ).

Physics sucks.

 

[Omnivore]

Not intending to be insulting but consider the following. Replace romance with the definition of it you all are using: fantasy. Then we have, since physics is simply a description of reality, the statement you are expressing is, boiled down, simply: "Reality ruins fantasy.".... well duh..

Traveller is fantasy with a science flavor. Applying hard science with known physics is going to cause headaches every time, especially if you have preconceived notions about whatever portion of it you are examining.

Traveller itself is riddled with preconceived notions that, when you examine them in detail with the scalpel of physics, don't work out so well. The 'lets add a myriad of details' phase it went through some years back did nothing to help - in fact made the problems far worse.

In this case, the mass detector idea is flawed. What? But that's based on reality! Yes and being applied to fantasy.. a fantasy where gravitics is in widespread use. Imagine trying to see using IR goggles while inside a steel mill. Half the systems on the ship use gravitics technology - talk about a noisy environment!

Imagine trying to see using IR goggles while inside a steel mill. Half the systems on the ship use gravitics technology - talk about a noisy environment!

 

[rancke]

Not intending to be insulting but consider the following. Replace romance with the definition of it you all are using: fantasy. Then we have, since physics is simply a description of reality, the statement you are expressing is, boiled down, simply: "Reality ruins fantasy.".... well duh..

It's not fantasy just because it contradicts reality; lot's of science fiction contradicts reality.

Traveller is fantasy with a science flavor. Applying hard science with known physics is going to cause headaches every time, especially if you have preconceived notions about whatever portion of it you are examining.

Traveller is Science Fiction.

"The settings for science fiction are often contrary to consensus reality, but most science fiction relies on a considerable degree of suspension of disbelief, which is facilitated in the reader's mind by potential scientific explanations or solutions to various fictional elements. Science fiction elements include:

* A time setting in the future, in alternative timelines, or in a historical past that contradicts known facts of history or the archaeological record. [Check]
* A spatial setting or scenes in outer space (e.g. spaceflight), on other worlds, or on subterranean earth.[3] [Check]
* Characters that include aliens, mutants, androids, or humanoid robots. [Check]
* Futuristic technology such as ray guns, teleportation machines, and humanoid computers.[4] [Check]
* Scientific principles that are new or that contradict accepted laws of nature, for example time travel, wormholes, or faster-than-light travel. [Check]
* New and different political or social systems, e.g. dystopia, post-scarcity, or a post-apocalyptic situation where organized society has collapsed.[5] [?]
* Paranormal abilities such as mind control, telepathy, telekinesis, and teleportation. [Check]
* Other universes or dimensions and travel between them. [Check]"

-- Wikipedia​

Some people focus on one half of the term -- science -- and gets the fallacious notion that SF can't have elements that contradict known science. That just happens not to be true.

Traveller itself is riddled with preconceived notions that, when you examine them in detail with the scalpel of physics, don't work out so well. The 'lets add a myriad of details' phase it went through some years back did nothing to help - in fact made the problems far worse.

As is the case with lots of science fiction.

In this case, the mass detector idea is flawed. What? But that's based on reality! Yes and being applied to fantasy.. a fantasy where gravitics is in widespread use. Imagine trying to see using IR goggles while inside a steel mill. Half the systems on the ship use gravitics technology - talk about a noisy environment!

No, it's being applied to science fiction.

There are a number of tropes that belong to SF. There are a number of tropes that belongs to Fantasy. And there are some tropes common to both genres. If a body of work has tropes belonging only to one of the two or to the common pool, it belongs to that genre. Traveller has only SF tropes and tropes common to both SF and Fantasy. Therefore, Traveller is Science Fiction. Q.E.D.


Hans

 

[Cryton]

Well said Hans.

EDIT: OK. Wow. I guess I should explain myself...

I said "Well said Hans." after a particularly well written posting by Rancke2 (Hans).

I viewed his posting as a reminder to all of us that Science Fiction is a form of Fantasy, though it is one that many of us like with a healthy dose of Science.

I in no way meant to offend anyone.

Guess I will have to make my postings longer than three words from now on.

With great power comes great responsibility....:rofl:

 

[Omnivore]

Science fiction (noun):
Fiction dealing principally with the impact of actual or imagined science on society or individuals, or more generally, literary fantasy including a scientific factor as an essential orienting component.

 

[rancke]

Science fiction (noun):
Fiction dealing principally with the impact of actual or imagined science on society or individuals, or more generally, literary fantasy including a scientific factor as an essential orienting component.

Ah, you meant fantasy as in imaginary, not fantasy as in the literary genre? I'm sorry. I was mislead by the fact that your statement that 'reality ruins fantasy' is also wrong if you mean imaginary. An imaginary story can be starky realistic. All fiction is fantasy in that sense.

In that case, I've no idea what you were trying to say.



Hans

 

[HG_B]

Imagine trying to see using IR goggles while inside a steel mill. Half the systems on the ship use gravitics technology - talk about a noisy environment!

I've done that. Actually they are sometimes used in such environments. I think you have a more tenuous grasp on technology than you think...