Outsider Tech: Sensors

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Just a Crazy-Man
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Outsider Tech: Sensors

Post by Just a Crazy-Man »

I was wondering how sensors and detection would work as the Light Second and time delay looking at the extra with fuel and previous talk of ground warfare or range and detection while jump points and sensor stations plus relay by coms info still so much.

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Arioch
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Re: Outsider Tech: Sensors

Post by Arioch »

Just a Crazy-Man wrote:I was wondering how sensors and detection would work as the Light Second and time delay looking at the extra with fuel and previous talk of ground warfare or range and detection while jump points and sensor stations plus relay by coms info still so much.
I think that most ships and stations, and certainly all warships and military stations, will have a full sensor suite of both active and passive detectors. I think that most detection at long ranges will be passive, with electromagnetic detectors on a wide range of frequencies. Starships in Outsider are not stealthy; they generate an immense amount of power and emit a lot of light and heat, especially when the drives are active or when firing weapons, which can be easily seen from across the system (unless there is something blocking the signal). The jump event itself also generates a strong EM pulse. Any ship or station with weapons will also have active sensors (radar or lidar whatever frequency they will use for that at TL10) to aid with fire control at close range.

As long as there are working sensors in the system, detection is more or less automatic, unless there is some unusual mitigating factor (like a dust disk, etc.), or the ship is literally hiding behind something like a planet or other boy. A ship may remain unnoticed if it "runs silent" with engines off and EM emissions at a minimum, but it will still be a hot target and may still be observed if the enemy knows where to look for it. Methods of confusing sensors such as jammers, decoys, chaff and flares can be used, though due to the sophistication of starship information processing systems they will usually only have any effectiveness against the active sensors of seeking weapons at close range.

All of the friendly ships and stations in a system will form a network sharing detection information; in friendly systems there will be additional infrastructure like system buoys and relays to support this network, to better share and preserve data and reduce lag time. Sensor displays will show timestamped last position and vector of known contacts. Because jump zones can be up to 40 light minutes from the system primary, depending on your location in the system the lag from last known contact can be more than an hour. But since effective beam weapons range is less that one light second in most cases, you'll be close enough to have a very good idea of where your target is before you can fire on it.

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Re: Outsider Tech: Sensors

Post by kiwi »

Do you think that if you rigged a mirrored 'sail' to your ship you could hide behind it? You could reflect all your infrared emissions back away from the presumed enemy sensors. You certainly couldn't hide all your emissions, but maybe a substantial arc of them...

I guess the difficulty would be getting in-system (with accompanying jump flash) without someone noticing.

And if someone does notice, but pretends otherwise, they could arrange for a very nasty surprise.

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Re: Outsider Tech: Sensors

Post by cacambo43 »

kiwi wrote:Do you think that if you rigged a mirrored 'sail' to your ship you could hide behind it? You could reflect all your infrared emissions back away from the presumed enemy sensors. You certainly couldn't hide all your emissions, but maybe a substantial arc of them...

I guess the difficulty would be getting in-system (with accompanying jump flash) without someone noticing.

And if someone does notice, but pretends otherwise, they could arrange for a very nasty surprise.
You'd have to have the ability to allow the 'sail' to emit the same 'radiation' as the background, else your sail is going to show up regardless, either because it will have a different set of emissions on its own, or there would be a telling lack of emissions - a shadow - right where you are hiding. I see this as being relevant in a planetary system where you'd presumably have a relatively large quantity of warm dust providing an IR back-glow. Maybe less relevant if you are in deep space.

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Arioch
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Re: Outsider Tech: Sensors

Post by Arioch »

No "sail" is ever going to be at absolute zero; not that you would want it to be. Though I think it's kind of a misconception that an object that's slightly below or above the temperature of the CMB will be instantly noticeable. In a solar system with literally billions of small cold objects, against a backdrop of hundreds of billions of visible stars and galactic gas and dust, I doubt whether any sensor/analysis system will be able to constantly examine the entire sky moment to moment with the resolution and sensitivity to detect a ship that isn't doing anything. But if you know which patch of sky to focus in on, and you have enough time to watch for movement and occultations, etc., then you can probably eventually find a target in direct line of sight no matter how it tries to hide.

A sail isn't going to make you invisible, since the sail itself will be visible (and a reflective sail will return active sensor pulses quite nicely). The sail will also block your view of the enemy. If you want to hide, you're probably better off just finding a comet or asteroid and hiding behind that.

But if you're in the same system as the enemy and they somehow don't know you're there, I think you can probably evade detection for quite some time just by lying quiet. But the moment you actually do anything useful (such as maneuver, fire weapons, or even send a signal), they will most likely be able to detect you.

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Re: Outsider Tech: Sensors

Post by cacambo43 »

I was thinking of scenarios where the ship was known to be in the system, nearby.

Regardless, I agree. Just laying low would be a good approach. Of course, given the distribution of objects in a system (assuming it's like our own Solar System) you might have quite a bit of distance to travel to get to said asteroid or comet. Space is BIG.

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Re: Outsider Tech: Sensors

Post by Krulle »

A "sail" could be difficult to maintain, as I imagine the solar wind would blow it in a certain direction...

Also, its use may otherwise be doubtful, as you'd have to be in system before the enemy is, as the jump drive's EMP would give away someone entered or left, and every sensor would then watch that part of the sky until they're sure no-one is "here".... And preparing for such a case, I imagine you could come up with much better solutions, like hiding in an asteroid disk, or planetary ring system, or behind a moon, or something similar, instead of deploying a gigantic mirror...
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Re: Outsider Tech: Sensors

Post by Just a Crazy-Man »

I wonder what of Quantum Communication is there a means to detect that?

Or yeah what of radio or video like all those signals that move through space over time can be detected?

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Re: Outsider Tech: Sensors

Post by Arioch »

Just a Crazy-Man wrote:I wonder what of Quantum Communication is there a means to detect that?
If you're referring to some kind of faster-than-light communication system based on the principle of quantum entanglement, none of the major combatants has such a thing.
Just a Crazy-Man wrote:Or yeah what of radio or video like all those signals that move through space over time can be detected?
Signals based on electromagnetic waves of whatever frequency are limited to the speed of light, and may be detected by a third party unless the signal is on a very tight beam between sender and receiver, and careful precautions are taken to ensure that stray photons are kept to a minimum.

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Re: Outsider Tech: Sensors

Post by MBehave »

Gravity can always be detected in real time, gravity waves(ripples) in space itself travel at the speed of light but its a forgotten inconvenience that gravity experiments show the suns real position and not its 8min light lag position is effecting Earth in real time. I say inconvenience because its in direct conflict with currently accepted models yet is proven repeatable and verifiable and yet ignored.
Quantum gravity sensors are planned to be used to map the outer solar system, the planned missions will create raw data that will need to be processed, but since humans can do it today(just not real time) no reason advanced interstellar races cant do it in real time.

Quantum Gravity sensors detect actual changes in gravity and not the ripples unlike non quantum based gravity sensors that detect ripples caused by gravity not the actual "pull" of gravity.

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Re: Outsider Tech: Sensors

Post by Arioch »

MBehave wrote:Gravity can always be detected in real time, gravity waves(ripples) in space itself travel at the speed of light but its a forgotten inconvenience that gravity experiments show the suns real position and not its 8min light lag position is effecting Earth in real time. I say inconvenience because its in direct conflict with currently accepted models yet is proven repeatable and verifiable and yet ignored.
Quantum gravity sensors are planned to be used to map the outer solar system, the planned missions will create raw data that will need to be processed, but since humans can do it today(just not real time) no reason advanced interstellar races cant do it in real time.

Quantum Gravity sensors detect actual changes in gravity and not the ripples unlike non quantum based gravity sensors that detect ripples caused by gravity not the actual "pull" of gravity.
Atom interferometry can provide hyper-accurate measurements of the gravity field at a particular point in space, but it seems from what I can gather that accurate mapping of the gravitational "topography" an area requires the detector to take many readings across that area. Planned projects to map Earth's gravitational field will deploy satellites to orbit the planet; as far as I can tell, a single stationary detector on the planet's surface won't do the job. And though I didn't find any information on planned mapping of the outer solar system using this method, I'm assuming that it entails sending a probe through the area to be mapped, which will take years, if not decades. I'm not sure that a quantum gravity detector on a warship is going to be able to tell you any more about distant changes in the positions of small objects in the solar system in real-time than optical sensors will. But even if it could instantly and accurately map every one of the billions of objects in the system down to the mass of a ship, this is still as large of a data analysis challenge as picking out optical signals against the background clutter. I don't think it changes the basic detection picture.

As to the speed of the sensing of the gravitational field, it makes some sense to me that the Earth accelerates in its orbit according to the curvature of space-time as it is now, and not according to what it was 8.3 minutes ago. But the recent detection of both gravitational and optical signals from the GW170817 neutron star merger clearly demonstrates that gravity waves are limited to the speed of light, and so it follows that information from the shift in a gravity well created by a ship accelerating under its own power cannot reach a detector faster the speed of light. Even when there are apparent effects that seem to happen faster than light, physics seems to be structured such that you can never benefit from them to get usable information faster than light.

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Re: Outsider Tech: Sensors

Post by Mithramuse »

MBehave wrote:Gravity can always be detected in real time, gravity waves(ripples) in space itself travel at the speed of light but its a forgotten inconvenience that gravity experiments show the suns real position and not its 8min light lag position is effecting Earth in real time. I say inconvenience because its in direct conflict with currently accepted models yet is proven repeatable and verifiable and yet ignored.
This isn't something I'm totally up to date on, but I recall reading about this around the time of the neutron star collision and... I don't think your statement is quite correct? In essence the sun or other star can/should be set up as a static field, with Earth (or whatever) moving through that field, and yes, then whatever is moving through the static field responds to the 'real' position and not the light-lagging position. This behavior has also been shown for EM fields as well, IIRC.

IIRC stuff breaks down a bit if trying to have both systems in motion but that is more a consequence of the math used; if the systems are updated so one object is considered stationary relative to the other, no issue. I believe this is the currently accepted model, so there's no conflict as far as I know. Would love to read some references (though it's not like I'm producing any, either, I know).
MBehave wrote:Quantum gravity sensors are planned to be used to map the outer solar system, the planned missions will create raw data that will need to be processed, but since humans can do it today(just not real time) no reason advanced interstellar races cant do it in real time.

Quantum Gravity sensors detect actual changes in gravity and not the ripples unlike non quantum based gravity sensors that detect ripples caused by gravity not the actual "pull" of gravity.
Not sure what the effective range would be for measuring something small, vs. the large gongs of stellar mass collisions and the like, but again, sounds neat. This is akin to NASA's GRACE satellite pair?

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Re: Outsider Tech: Sensors

Post by icekatze »

hi hi

In realistic space flight, there's a big trade-off between the ability to hide, and the ability to be useful. It's possible to stay like a stationary lump and be mostly unseen, but at that point, that is pretty much an object's primary function. If an object wants to move to approach a target in any reasonable amount of time, staying hidden becomes a phenomenally difficult challenge.

Compared to electromagnetics, gravity is a remarkably weak force. The quantum gravity sensor is like the LIGO, but are limited in that they only work in the direction of the strongest gravity source. The sensors need to be directly over the object they are measuring, as the superpositioned rubidium atoms can only fall in the direction of the gravity field.

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Re: Outsider Tech: Sensors

Post by MBehave »

Quantum gravity sensors are already being used for things such as mapping oilfields and the flow of underground rivers and detecting different types of ore deposits.
While a single ship may have trouble mapping a large area quickly a fleet would not, interpolating the data of each vessel would give precise locations for weapons targeting.
The only delay would be the communication/processing delay between ships, but even just 3 ships separated by a 100km from each other would give extremely accurate data for targeting with the majority of the delay being processing.

Considering the level of processing power Historians have in reading/writing solid state data I think they at least should have the processing capacity to process gravity sensor data in real time with accuracy allowing combat.
Arioch wrote:
MBehave wrote:Gravity can always be detected in real time, gravity waves(ripples) in space itself travel at the speed of light but its a forgotten inconvenience that gravity experiments show the suns real position and not its 8min light lag position is effecting Earth in real time. I say inconvenience because its in direct conflict with currently accepted models yet is proven repeatable and verifiable and yet ignored.
Quantum gravity sensors are planned to be used to map the outer solar system, the planned missions will create raw data that will need to be processed, but since humans can do it today(just not real time) no reason advanced interstellar races cant do it in real time.

Quantum Gravity sensors detect actual changes in gravity and not the ripples unlike non quantum based gravity sensors that detect ripples caused by gravity not the actual "pull" of gravity.
Atom interferometry can provide hyper-accurate measurements of the gravity field at a particular point in space, but it seems from what I can gather that accurate mapping of the gravitational "topography" an area requires the detector to take many readings across that area. Planned projects to map Earth's gravitational field will deploy satellites to orbit the planet; as far as I can tell, a single stationary detector on the planet's surface won't do the job. And though I didn't find any information on planned mapping of the outer solar system using this method, I'm assuming that it entails sending a probe through the area to be mapped, which will take years, if not decades. I'm not sure that a quantum gravity detector on a warship is going to be able to tell you any more about distant changes in the positions of small objects in the solar system in real-time than optical sensors will. But even if it could instantly and accurately map every one of the billions of objects in the system down to the mass of a ship, this is still as large of a data analysis challenge as picking out optical signals against the background clutter. I don't think it changes the basic detection picture.

As to the speed of the sensing of the gravitational field, it makes some sense to me that the Earth accelerates in its orbit according to the curvature of space-time as it is now, and not according to what it was 8.3 minutes ago. But the recent detection of both gravitational and optical signals from the GW170817 neutron star merger clearly demonstrates that gravity waves are limited to the speed of light, and so it follows that information from the shift in a gravity well created by a ship accelerating under its own power cannot reach a detector faster the speed of light. Even when there are apparent effects that seem to happen faster than light, physics seems to be structured such that you can never benefit from them to get usable information faster than light.

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Re: Outsider Tech: Sensors

Post by Arioch »

MBehave wrote:Quantum gravity sensors are already being used for things such as mapping oilfields and the flow of underground rivers and detecting different types of ore deposits.
I'm aware of that, but it's not a good demonstration of the case we're talking about, either in terms of time or distance.
MBehave wrote:While a single ship may have trouble mapping a large area quickly a fleet would not, interpolating the data of each vessel would give precise locations for weapons targeting.
The maximum weapons range for beam weapons is around 1 light second, or around 300,000 km. I haven't seen any evidence that quantum gravity sensors can provide instantaneous location information faster than the speed of light for a ship-sized target at these ranges (since, among other things, that would break the laws of physics as we know them), but it's kind of irrelevant for our purposes, since conventional active and passive EM sensors are adequate to accurately locate a target at this range.

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Re: Outsider Tech: Sensors

Post by icekatze »

hi hi

Quantum gravity sensors detect gravity, that's it. They detect it very precisely, but when they take a reading, they only return a number.

Things like underground rivers, ore deposits, and oil fields are interpolated based on a solid understanding of the surrounding area and its values. A quantum gravity sensor is functionally identical to a mass suspended from a spring, the only difference is that it is currently more precise. I don't see any reason to believe that they will ever be useful at long ranges.

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Re: Outsider Tech: Sensors

Post by Just a Crazy-Man »

So whats the best sensor array to have on a starship

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Re: Outsider Tech: Sensors

Post by kiwi »

Just a Crazy-Man wrote:So whats the best sensor array to have on a starship
For me, an Inertial Measurement Unit (IMU). Used in conjunction with other sensors to track spacecraft position, heading and velocity. Any other sensor array will ultimately reference this information in some way (eg in what direction is my telescope pointing?)

I guess you could argue that your master reference clock is most important, but it might be integrated into the IMU anyway.

I suppose that, with Outsider jump drives, you might want the best IMU and telescopes / star trackers you can afford (in terms of money, mass and volume) to minimise error on FTL jumps. Lest you come out inside a star or something...

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Re: Outsider Tech: Sensors

Post by MBehave »

may want to contact NASA then and tell them their plans to map objects to small/dark/cool for normal detection methods to detect by sending probes with Quantum Gravity sensors into the outer solar system is doomed to fail.
They seem to think they are more then good enough for EXACTLY that.
icekatze wrote:hi hi

Quantum gravity sensors detect gravity, that's it. They detect it very precisely, but when they take a reading, they only return a number.

Things like underground rivers, ore deposits, and oil fields are interpolated based on a solid understanding of the surrounding area and its values. A quantum gravity sensor is functionally identical to a mass suspended from a spring, the only difference is that it is currently more precise. I don't see any reason to believe that they will ever be useful at long ranges.

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Re: Outsider Tech: Sensors

Post by icekatze »

hi hi
MBehave wrote:may want to contact NASA then and tell them their plans to map objects to small/dark/cool for normal detection methods to detect by sending probes with Quantum Gravity sensors into the outer solar system is doomed to fail.
Wat? I mean, first off, citation please? Can you be specific? Which mission exactly are you talking about? I seriously can't tell what is hyperbole and what isn't here.

Second of all, how does a plan to send probes into the outer solar system equate to effective real time gravity sensors on combat vessels?

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