Lord Kalvan of Otherwhen
SOC-7
When a ship jumps into a system, can it be determined where it is coming from?? (i.e. does it "appear" travelling in a specific vector or is it stationary?)
When a ship jumps in...
- Thread starter Lord Kalvan of Otherwhen
- Start date
If I recall correctly it has the same vector it had before jumping.
About the exact location of its appearnace, I don't know; in Babylon 5 it was a matter of technology when you get out of hyperspace, with the high-tech races (Minbari for example) being able to do it far more accurately than the Earthers, but I don't recall any Traveller convention in this direction.
About the exact location of its appearnace, I don't know; in Babylon 5 it was a matter of technology when you get out of hyperspace, with the high-tech races (Minbari for example) being able to do it far more accurately than the Earthers, but I don't recall any Traveller convention in this direction.
mike wightman
SOC-14 10K
In some versions of the Traveller rules it is possible to analyse jump flash data, but not all even have a noticable emergence event.
It's definitely a case of make it up to get what you want.
It's definitely a case of make it up to get what you want.
Liam Devlin
SOC-14 5K
Interesting question Lord Kalvan!
I know from past Traveller versions, we have the ability to try and track by sensors where a ship was jumping out to; this is a first to see if one can detect where a ship has jumped from.
I would presume if the first is possible, then your reverse must also be true--provided (as with the jump-out)the ship's sensors operator, Ship's model/# sensors had the range & the operator the skill to determine such a thing.
I know from past Traveller versions, we have the ability to try and track by sensors where a ship was jumping out to; this is a first to see if one can detect where a ship has jumped from.
I would presume if the first is possible, then your reverse must also be true--provided (as with the jump-out)the ship's sensors operator, Ship's model/# sensors had the range & the operator the skill to determine such a thing.
TheEngineer
SOC-14 1K
Hi !
Well, depends largely on the way YTU works
I think, there was a pretty similar question here a while ago, but I cannot find this topic anymore...
Basically, the ships transponder might tell about the departure world, but thats perhaps information only accessible by officials (or by hackers).
Or there is already flight information present at the systems port authority, transferred by some ships ahead in schedule (well, good for ships working in schedule).
Here I just assume, that as soon as a departure is scheduled, this information is forwarded to other system authorities (via ship mail), even if it is not sure, that it arrives there before the actuall ahip does.
A ships movement vector could be considered only as a hint on the departure world. Of course this vector could be adapted prior jump (for safety reasons or to hide information), so that it appears to be nearly "stationary".
If you assume a straight jump line between departure and destination points, solid objects gravitational fields reduce navigational freedom, so that some departure worlds could perhaps be excluded.
IMTU jump space navigation is possible, so this way to exclude departue worlds is not given.
Well, using sensors you could get information about the ships jump performance. With better sensors (densiometers) you even could see how much jump fuel is left in the tanks.
So, having jump distance travelled and excluded directions the departure world list could be narrowed further.
Generally it really might depend on the equipment, the (political) power and the afford you are willing to invest, if you can find out, where somebody comes from.
But, as I said its a YTU thing. AFAIK "canon" does not include information about that.
regards,
Mert
Well, depends largely on the way YTU works
I think, there was a pretty similar question here a while ago, but I cannot find this topic anymore...
Basically, the ships transponder might tell about the departure world, but thats perhaps information only accessible by officials (or by hackers).
Or there is already flight information present at the systems port authority, transferred by some ships ahead in schedule (well, good for ships working in schedule).
Here I just assume, that as soon as a departure is scheduled, this information is forwarded to other system authorities (via ship mail), even if it is not sure, that it arrives there before the actuall ahip does.
A ships movement vector could be considered only as a hint on the departure world. Of course this vector could be adapted prior jump (for safety reasons or to hide information), so that it appears to be nearly "stationary".
If you assume a straight jump line between departure and destination points, solid objects gravitational fields reduce navigational freedom, so that some departure worlds could perhaps be excluded.
IMTU jump space navigation is possible, so this way to exclude departue worlds is not given.
Well, using sensors you could get information about the ships jump performance. With better sensors (densiometers) you even could see how much jump fuel is left in the tanks.
So, having jump distance travelled and excluded directions the departure world list could be narrowed further.
Generally it really might depend on the equipment, the (political) power and the afford you are willing to invest, if you can find out, where somebody comes from.
But, as I said its a YTU thing. AFAIK "canon" does not include information about that.
regards,
Mert
The Oz
SOC-14 1K
IMTU it is possible to use the incoming ship's vector to determine where the ship came from, if the incoming ship has plotted the most efficient course to go from the prior star system to this one. Merchant navigators routinely do this, to minimize transit time. Military navigators usually this but sometime plot deceptive jump vectors, just for practice or to prevent someone from knowing where they are from/going.
Andrew Boulton
The Adminator
Of course, depending on the jump rating there might not be many possible systems it could have come from.
Cpl. Morrison(1),
With regards to analysing 'jump flash', MT made some vague noises about it and TNE finally spoke up about it but both limited themselves to departures only. Even then, TNE qualified its statement with a lot of maybes and sometimes.
There is an arrival flash too, but no version has ever suggested that it can be analysed for any information beyond "A Ship Arrived".
Just how easily any jump flash can be detected is something that has never been officially determined. GT:FI has a sidebar concerning an IISS elint mission arriving in a system deep within the Consulate. The crew takes care to exit near a gas giant in order to 'smother' their jump flash with all the other 'noise' gas giants produce.
Because jump flash is so vague in canon many people have taken the idea and, IMHO, expanded it all out of proportion. While I have no problem with military sensors and military processors routinely picking up some jump flashes and occasionally deriving limited information from them, the idea that Cap'n Blackie aboard the free trader Suffering Bastard orbiting Arglebargle-IX can 'read' a system-full of jump flashes for arrival and departure information is just a bit too much.
YMMV.
As Mr. Boulton points out, a good estimate of a vessel's departure system or it's destination can be made by weaving together several strands of different information. What is its jump rating? What sort of vector does it have upon arrival? What sort of vector did it take during departure? Where in the system did it arrive or depart and does that point to any jump masking? Ferreting out a vessel's departure or destination system can be roleplayed in this manner, which is much more fun than merely reading a name off a sensor display.
Have fun,
Bill
1 - Seeing as we're not in an Aryan-Transpacific timeline, I decided to use your real name.
With regards to analysing 'jump flash', MT made some vague noises about it and TNE finally spoke up about it but both limited themselves to departures only. Even then, TNE qualified its statement with a lot of maybes and sometimes.
There is an arrival flash too, but no version has ever suggested that it can be analysed for any information beyond "A Ship Arrived".
Just how easily any jump flash can be detected is something that has never been officially determined. GT:FI has a sidebar concerning an IISS elint mission arriving in a system deep within the Consulate. The crew takes care to exit near a gas giant in order to 'smother' their jump flash with all the other 'noise' gas giants produce.
Because jump flash is so vague in canon many people have taken the idea and, IMHO, expanded it all out of proportion. While I have no problem with military sensors and military processors routinely picking up some jump flashes and occasionally deriving limited information from them, the idea that Cap'n Blackie aboard the free trader Suffering Bastard orbiting Arglebargle-IX can 'read' a system-full of jump flashes for arrival and departure information is just a bit too much.
YMMV.
As Mr. Boulton points out, a good estimate of a vessel's departure system or it's destination can be made by weaving together several strands of different information. What is its jump rating? What sort of vector does it have upon arrival? What sort of vector did it take during departure? Where in the system did it arrive or depart and does that point to any jump masking? Ferreting out a vessel's departure or destination system can be roleplayed in this manner, which is much more fun than merely reading a name off a sensor display.
Have fun,
Bill
1 - Seeing as we're not in an Aryan-Transpacific timeline, I decided to use your real name.
jfetters
SOC-14 1K
Specifically, from RSB:
It then goes on to say regarding precipitation:
So, what everyone is saying here makes sense - with some wizardry, you can monitor an outgoing vessel and get an idea as to where it is headed to a certain degree.
Arrival is a different proposition, however, just because of how damned BIG space is. I mean, you would have to have sensor focussed on one specific peice of space fabric in order to get any useable data, and that is a pretty big long shot. We're talking smaller than needle-in-haystack odds here.
Also, to further complicate this issue, is the matter (also covered in RSB) of "c-lag" where the in-station ships will not see the inbound ship for a couple of hours, dependent upon where the ships are in relation to each other.
B
Black Globe Generator
Guest
IM(C)TU it's a throw of 15+ using Navigation skill to determine a ship's probable point-of-origin or destination - the target ship must be actively tracked by sensors to permit the throw, so determining point-of-origin or destination based on the elusive "jump flash" isn't possible.
All Imperial naval bases and many type A starports IMTU have a specific sensor array designed to search for jump flashes, but they are anything but 100% effective.
Also, as an aside, starships IMTU may not enter jump space with a vector greater than 100mm - no boosting all the way to the jump point, or emerging from jump space with a six-meter long vector!
All Imperial naval bases and many type A starports IMTU have a specific sensor array designed to search for jump flashes, but they are anything but 100% effective.
Also, as an aside, starships IMTU may not enter jump space with a vector greater than 100mm - no boosting all the way to the jump point, or emerging from jump space with a six-meter long vector!
Plankowner
SOC-13
BGG, are those vector limits imposed by law or nature?
Is it something that the computer just won't let you do or something that cannot be physically done?
Is it something that the computer just won't let you do or something that cannot be physically done?
Liam Devlin
SOC-14 5K
Frankly speaking, I did some thinking on this last night, as we had this past Friday an attempt by players to ascertain where a hostile ship was jumping out to.
Unless the PC's know what the inbound ship has "under the hood" (jump-drive-wise), they'll be guessing still which of 1-5 parsecs it came from.
We use T20, so in the T/Sensors skill table their Model/4 could:
* Ship detection: X3 (420,000km)
*Detect Comm signal: X3 (420,000Km)
*Displacement Scan: X2 (360,000Km)
*Configuration scan: X1 (300,000km)
*Threat Assessment: VL (240,000km)
Target vessel sat 490,000Km away (two range bands for detection at -4DM)--which they made readily, negating the Computer Model DM.
They made the displacement scan (4x range bands -8 DM to roll) barely. Success was minimal, so they got the "iffy answer" of that it was between 200-300dtons.
Configuration Scan (made at 5 range bands diff at -10) was also barely successful, and showed a vessel of a A2 Far Trader build with two turrets (normally a J-2/2G book designed ship, right?)
The Threat assessment check--(what are they up to?) was made at -6 range bands away (-12DM), and they blew it, so they had no idea where it was going.
Add to this, IMTU in the TNE, the ship may not have its original Jump drive or power plant in a Wilds campaign area..
Even if they had deduced vector, etc etal--they'd been guessing which 1-4 maybe parsecs a shp that size could go.
YMMV. Thanks guys.
[edited for spelling]
Unless the PC's know what the inbound ship has "under the hood" (jump-drive-wise), they'll be guessing still which of 1-5 parsecs it came from.
We use T20, so in the T/Sensors skill table their Model/4 could:
* Ship detection: X3 (420,000km)
*Detect Comm signal: X3 (420,000Km)
*Displacement Scan: X2 (360,000Km)
*Configuration scan: X1 (300,000km)
*Threat Assessment: VL (240,000km)
Target vessel sat 490,000Km away (two range bands for detection at -4DM)--which they made readily, negating the Computer Model DM.
They made the displacement scan (4x range bands -8 DM to roll) barely. Success was minimal, so they got the "iffy answer" of that it was between 200-300dtons.
Configuration Scan (made at 5 range bands diff at -10) was also barely successful, and showed a vessel of a A2 Far Trader build with two turrets (normally a J-2/2G book designed ship, right?)
The Threat assessment check--(what are they up to?) was made at -6 range bands away (-12DM), and they blew it, so they had no idea where it was going.
Add to this, IMTU in the TNE, the ship may not have its original Jump drive or power plant in a Wilds campaign area..
Even if they had deduced vector, etc etal--they'd been guessing which 1-4 maybe parsecs a shp that size could go.
YMMV. Thanks guys.
[edited for spelling]
B
Black Globe Generator
Guest
IMTU, it's a physical limitation - a ship cannot create a jump bubble if its vector exceeds 100mm.
Liam Devlin
SOC-14 5K
It is in this threat assessment stage of detection the Sensor Operator would gain the knowledge of where its going to/ coming from. Seeing it arrive is one thing--knowing where it comes from another, and as one can see, the better the computer model sensors, better your chances, coupled with the player's T/Sensor skill.
BUT...if its not a standard-built ship, and they don't have say a Library program in their computer ofr IDP (Imperial Design Plan) ships..then unless they know the vessel's history itself (maybe surplus Type T sold off, but owner wanted more cargo space so sold off the J-3 for a J-2 and re-worked the bunkerage space which players aren't privy to), they'll still be guessing.
Knowing & guessing boils it down guys.
BUT...if its not a standard-built ship, and they don't have say a Library program in their computer ofr IDP (Imperial Design Plan) ships..then unless they know the vessel's history itself (maybe surplus Type T sold off, but owner wanted more cargo space so sold off the J-3 for a J-2 and re-worked the bunkerage space which players aren't privy to), they'll still be guessing.
Knowing & guessing boils it down guys.
I see other Travallerfiles (did I use that term correctly?) like what I read also. They have to like it to use names from them as their alter-egos here. IE LD & LCOO
I never had anyone ask this before but IMHO, a guess might be made, IF you were in a military equiped ship and, IF you managed to record the entire first say 5 combat turns of movement after entry to normal space and, IF you had the right crew with the right skills in position th do all the above AND, IF you roleplayed it good enough to convince me you knew what you were attempting to do. If you role play it good enough with me, you can cover a lot of SLOPPY scientific garbage (after all this is science fiction)
I never had anyone ask this before but IMHO, a guess might be made, IF you were in a military equiped ship and, IF you managed to record the entire first say 5 combat turns of movement after entry to normal space and, IF you had the right crew with the right skills in position th do all the above AND, IF you roleplayed it good enough to convince me you knew what you were attempting to do. If you role play it good enough with me, you can cover a lot of SLOPPY scientific garbage (after all this is science fiction)
princelian
SOC-12
IMTU, there are FTL sensors that can perceive energy moving through the lowest bands of hyperspace. (See my posts regarding microjumps in the IMTU forum for more information on that.) These sensors are in actuality the jump crystals of the ship with all kinds of sensing devices monitoring them. Jump crystals only grow in horrendously nasty atmospheres and are incredibly dangerous to mine - and have to be mined by humans; robotic brains are degraded rapidly by their emanations - and are also quite expensive. They also "ring" when hyperspace energy moves across them.
When a ship enters hyperspace, there is a "ring" on the jump crystals of every ship nearby, and the Imperial Navy calls this a "primary contact," as in "primary drive" = jump drive. This happens at quite a long range (1 AU/ton/jump number at TL10, so a Type-S scout jumping out at J-2 can be picked up, by civilian-grade sensors, at 200 AU). Mil-spec sensors are longer-ranged, capable of detecting the same hyperspace departure at a range of <CONTENT CLASSIFIED AND DELETED>. (For MTU, mil-spec sensors have twice (passive) to three times (active) the range of civilian sensors.)
Higher-tech jump engines are more efficient in their usage of power to open the hole into J-space, so they emanate at a shorter range (inveresly proportional to TL, so at TL15, a Type-S entering a J-2 jump is 200 * 10/15 = 133.3 AU).
A ship departing realspace just vanishes from view; other than the J-space emissions, there isn't any evidence of the departure.
A ship returning to R-space from J-space, however, brings some of the incredible, incalculable energies of J-space back with them, and most of this is radiated as visible light. Thus, if you're close enough to see a ship emerging from J-space, there is a brief display of coruscating rainbow light (and IR, UV, and X-ray radiation, none of which is damaging if you're in a ship) as well as a propagating J-space signal.
This light display, whose intensity is based solely upon the tonnage of the ship, can be picked up by ship's sensors at moderate range (1 AU/100 tons).
The J-space signal for an arriving vessel is not as strong as the outbound signal, and is limited to 1 AU/100 tons/jump number, so that same Type-S scout sends out a hyperspace signal at 2 AU. It's MUCH harder to detect inbound ships than outbound ones.
Now, if you know the tonnage of the ship that's arriving or departing, you can determine how far they went, assuming you can see the signal. Any ship jumping from about 105 D will be well within the detection envelope of standard sensors, so this information is easily obtained. And since you don't jump exactly 2 parsecs at J-2 - you're actually jumping 1.855331 parsecs to go from Regina to Yori - the course of the jumping ship can be inferred from the power of the jump signal.
(Same for inbound ships, but at shorter ranges...however 2 AU is still well within the 100 D jump target for most ships.)
None of this gives you any information on the exact course that the jumping ship is using, so someone jumping at 1.855331 parsecs from Regina might actually be heading for Forboldn, and accepting the extra realspace maneuvering at the end to avoid being chased by that 600-ton corsair that's been following them. However, most fatcats follow least-time courses that can be taken advantage of by an enemy, if the enemy is patient.
Merchant ship jumps 1.855331 parsecs from Regina on a least-time course to Yori. Corsair, a few minutes later, jumps 1.855331 parsecs to Yori as well, hoping that the random timing of jumping makes them arrive first. If they do, they can lay a trap for the merchie. If they don't, they refuel and wait for the next merchie to jump out from Yori (maybe the same one) and try again. And there's always the chance the merchie had a minor navigational error and even though they arrive before you do, they're outsystem and have to accelerate in toward the planet....
When a ship enters hyperspace, there is a "ring" on the jump crystals of every ship nearby, and the Imperial Navy calls this a "primary contact," as in "primary drive" = jump drive. This happens at quite a long range (1 AU/ton/jump number at TL10, so a Type-S scout jumping out at J-2 can be picked up, by civilian-grade sensors, at 200 AU). Mil-spec sensors are longer-ranged, capable of detecting the same hyperspace departure at a range of <CONTENT CLASSIFIED AND DELETED>. (For MTU, mil-spec sensors have twice (passive) to three times (active) the range of civilian sensors.)
Higher-tech jump engines are more efficient in their usage of power to open the hole into J-space, so they emanate at a shorter range (inveresly proportional to TL, so at TL15, a Type-S entering a J-2 jump is 200 * 10/15 = 133.3 AU).
A ship departing realspace just vanishes from view; other than the J-space emissions, there isn't any evidence of the departure.
A ship returning to R-space from J-space, however, brings some of the incredible, incalculable energies of J-space back with them, and most of this is radiated as visible light. Thus, if you're close enough to see a ship emerging from J-space, there is a brief display of coruscating rainbow light (and IR, UV, and X-ray radiation, none of which is damaging if you're in a ship) as well as a propagating J-space signal.
This light display, whose intensity is based solely upon the tonnage of the ship, can be picked up by ship's sensors at moderate range (1 AU/100 tons).
The J-space signal for an arriving vessel is not as strong as the outbound signal, and is limited to 1 AU/100 tons/jump number, so that same Type-S scout sends out a hyperspace signal at 2 AU. It's MUCH harder to detect inbound ships than outbound ones.
Now, if you know the tonnage of the ship that's arriving or departing, you can determine how far they went, assuming you can see the signal. Any ship jumping from about 105 D will be well within the detection envelope of standard sensors, so this information is easily obtained. And since you don't jump exactly 2 parsecs at J-2 - you're actually jumping 1.855331 parsecs to go from Regina to Yori - the course of the jumping ship can be inferred from the power of the jump signal.
(Same for inbound ships, but at shorter ranges...however 2 AU is still well within the 100 D jump target for most ships.)
None of this gives you any information on the exact course that the jumping ship is using, so someone jumping at 1.855331 parsecs from Regina might actually be heading for Forboldn, and accepting the extra realspace maneuvering at the end to avoid being chased by that 600-ton corsair that's been following them. However, most fatcats follow least-time courses that can be taken advantage of by an enemy, if the enemy is patient.
Merchant ship jumps 1.855331 parsecs from Regina on a least-time course to Yori. Corsair, a few minutes later, jumps 1.855331 parsecs to Yori as well, hoping that the random timing of jumping makes them arrive first. If they do, they can lay a trap for the merchie. If they don't, they refuel and wait for the next merchie to jump out from Yori (maybe the same one) and try again. And there's always the chance the merchie had a minor navigational error and even though they arrive before you do, they're outsystem and have to accelerate in toward the planet....
shadowdragon
SOC-12
the jumping ship would also carry some of the "stuff" from the system jumped from. the jump envelope extends a short distance from the ship. any matter near the ship would be taken along for the ride during the jump. at arrival, this matter is detectable by sensors, easily if the sensors detect the jump flash. this would allow the sensor operator the chance to analyze the foreign matter and maybe determine a matching star system. just scanning the area with a good enough sensor suite would allow the operator to estimate what systems had been jumped from recently, at least within the last several hours, days maybe.
Only what is contained in Jump Bubble would be carried into the next system, the rest would be vapourized by jumpspace. One of the reasons Grandfather created the jump space weaves was to solve the problem of the Heat Death of the Universe. As a way of displacing additional matter, entropy is slowed to more managable levels. Naturally, as an instellar civilization expands more energy is created over matter hence the need to build stargates then tap into the older wormhole network.
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