Miscellaneous Terran question-and-answer thread

[Arioch]

Do human vessels (or any others for that matters) leave any kind of "jump trace" or other emissions that can be used to track when a jump took place and where it might have gone to?

L.

There are no lasting traces that can be detected after the fact, but if you had sight of the ship during the process (or have recording buoys in the system), the ship's course will show you exactly where it went. Each nearby star has a corresponding jump zone and velocity vector.

[Luge]

Do human vessels (or any others for that matters) leave any kind of "jump trace" or other emissions that can be used to track when a jump took place and where it might have gone to?

L.

There are no lasting traces that can be detected after the fact, but if you had sight of the ship during the process (or have recording buoys in the system), the ship's course will show you exactly where it went. Each nearby star has a corresponding jump zone and velocity vector.

Hm, there goes one theory of mine. On the other hand: Good! That was a trope I always despised. "Sir, according to these energy readings/Mcguffin particles, the enemy ship went thataway three days ago!"

L.

[entity2636]

There are no lasting traces that can be detected after the fact, but if you had sight of the ship during the process (or have recording buoys in the system), the ship's course will show you exactly where it went. Each nearby star has a corresponding jump zone and velocity vector.

Do you mean the ships don't leave any sort of exhaust trail when they travel under power? The drives the "normal" species use aren't reactionless, meaning they should leave behind an ion or exhaust gas trail, that should be detectable against the average background particle counts in space, no?

[dragoongfa]

Unless said ship travels in 'dead space' then trying to follow a trail with exhaust particles is like trying to follow a car on a busy highway by following the few skid marks it leaves behind. Particles are also bound to fully disperse after a while, like smoke disperses in the air. I would wager that after a day or two there wouldn't be a trail left in regards to exhaust particles as they will be too dispersed to detect and analyze.

[entity2636]

More like following the tracks a jeep left in a grass field. True, the particles would disperse sooner or later, but not that soon, I'd say... The ships are quite large, have extremely powerful engines generating tremendous amounts of thrust and are bound to leave behind a considerable radiation trail. I'd wager such trails would be detectable for weeks or months even, if not near a frequently used flight corridor. True, however, that it would apply only for when a ship does a main engine burn to accelerate. When cruising or making minor course changes it will leave behind very little exhaust, if any.

[Arioch]

The exhaust of a Floater type drive is hot and radioactive, but it doesn't stay put... it's blasted out the tailpipe at rather high velocity. After a day or two it would be nowhere near the spot where it was emitted.

If you want to track what ships transit a certain jump point, just position a buoy somewhere nearby with a camera pointed at it.

[Luge]

From the Insider page on Jump Drives and Hyperspace, jumping is like a cannon shot. It specifically says that hyperspace and realspace don't interact, so no, there wouldn't be a vapour trail or exhaust trail to follow.

Like shooting from a cannon, there might be a lot of smoke and dust around right after the launch, but there's no way to tell which way the cannonball went unless you actually saw the cannon fire.

L.

[entity2636]

Exactly, the exhaust will travel at the speed it was emitted from the ship on a vector opposite the ship's course and have a density proportional to the power output of the drive, adjusted for the dispersal of particles and time past since it was emitted.

Luge - you're not entirely correct and unfortunately those "Mcguffin particles" do exist, at least for certain amount of time. What I mean is, and it's not in violation with Arioch's Hyperspace Laws *wink*, all of the above and Insider info on Hyperdrives state that there is a way of tracking a ship that traveled through a system some days prior. Granted, it is not easy and quick, but it can be done if you're determined, have time to spend and the necessary sensors on board.

Normal jumping between systems can only be done from predetermined "jump corridors" - the volume of space on a vector connecting two star systems that is located at a known distance from the source star. Plus each jump corridor leads only to one destination star (in systems like Leido there are multiple jump corridors that lead to multiple destinations, hence "Leido Crossroads". I'm not cooking up any crazy suicidal last resort stunt maneuvers that may violate Arioch's Laws and may or may not work under specific conditions, but thinking about normal jumping.

If you were to track a ship that jumped out of a system, you can detect and measure the exhaust trail it left behind when it accelerated using conventional propulsion. It will take you some time while you search and measure radiation levels and particle counts, but if not too much time has passed, you should be able to find the exhaust and determine it's speed, spread and intensity. From there you can trace back the vector the exhaust was emitted, engine power and time elapsed since it was emitted. From this you can then calculate the course the ship took and how long ago it happened and thus determine which jump corridor the ship went to and thus follow it.

Of course, that only works if the ship you're tracking went straight for the next jump point and didn't change course along it's route because changing a course will take much less engine power and leave behind much less exhaust that will be very very difficult to detect as it will be spread across an even larger volume of space and travel on a vector that's unpredictable for the one following the ship.

I would also dare to say this is how Clicky-27 followed SG51 from Naam all the way to Sala. Although Umiak ships are slower than Loroi, they were able to see which course SG51 initially took out of Naam and then follow their path through the other systems.

[SVlad]

I think exhaust travel at a speed close to the speed of light. So it is all about light speed delay. If you can see it, it's fine, also you are to late.

[Krulle]

And detecting takes longer than flying the path...
I this is your technology.... You'll be late anywhere.
This is a good way to find a hidden base, observer post, or similar, but not the way to pursuit enemies....

I would also dare to say this is how Clicky-27 followed SG51 from Naam all the way to Sala. Although Umiak ships are slower than Loroi, they were able to see which course SG51 initially took out of Naam and then follow their path through the other systems.

Visible light delay might also mean, the Umiak skipped into the system the Loroi fled to at about a time the Loroi leftit. The visible light they scatter just before they jump away is still hours away from reaching the point of the other jump points, so still visible.
Easy to follow...
Look for light and direct engine drives.

(43 lightminutes Sun<->Jupiter otbit, so jump points at Jupiter distance give you about 2 hours (3hours when jump point is on other side of sun in Jupiter orbit again) to optically follow the enemy, without them seeing you, your light has not reached them before they jump)

[Absalom]

Larger populations put pressure on food supplies, but improved agricultural technology stays ahead. There is a limit, but I think there is a lot of room to improve; direct genetic manipulations are producing gains that will make the Green Revolution seem trivial by comparison. There will be the same sorts of foods as are available today, along with new items that may either be exotic delicacies or cheap fodder. I think other resources such as energy and fresh water are probably of greater concern.

I'll bet that a lot of it comes down to farming the open ocean. Deep enough that sunlight doesn't reach, there's lots of nutrients afloat in the open ocean, but near the surface the primary restraint on plankton growth, and thereby ocean fertility, is the fact that most nutrients are trapped in cells already. Large scale wave-driven pumps could plausibly increase ocean fertility to a massive scale.

And once fusion lowers energy prices, you don't really have a freshwater problem. Just use high-intensity UV to break seawater into oxygen & hydrogen, burn & condense the off-gassing, and use the waste-heat to evaporate some more water for the condensers. If you want it inland but don't want to send the oxygen, decide whether to ship it as hydrogen or methane, separate it out (and optionally run through the Sabatier reaction), ship inland, burn in electrical generation plants. It's not free, but the primary issue is only energy cost.

More likely genetic engineering will have solved the issue some other way. As in, your genes will have been modified so that your body doesn't see the need to store a bunch of useless fat anymore.

Although gene therapy will be common as a treatment, I think outright genetic engineering of humans will probably still be illegal in most countries. So I don't think the fix is quite that simple.

Genetic engineering will probably be legally available and limited in 20-50 years in most countries, because of some genetic diseases (some folks died from treatments maybe a decade ago, but turns out that was because of the virus used, which has lead to some immunotherapies...). The idea of widespread prohibition of genetic therapies in several decades is highly dubious, and doubtlessly several major (and minor...) countries will allow genetic augmentations as well, and will quickly become the birth-countries of choice for the rich and famous, which in turn will cause it to become semi-accepted in almost all major countries.

Though Gataca is unlikely to actually lead to economic & social dominance, since personality is more likely to lead to failure than genetics.

It's hard to imagine a government that enforces a proscribed diet and compulsory exercise regimens that doesn't look suspiciously like IngSoc from 1984.

I'm not so sure about that. Any country where healthcare is distributed by the government has an incentive to ensure that citizens live healthily, as you said (or at least in a way that ensures that they require little healthcare during their life and then die as cheaply as possible.)
Given that countries with socialized medicine are already imposing sugar taxes on citizens I don't consider it unlikely that what you've described be brought about, and that it will be considered right and just in the popular mind that "everyone who is, after all, getting all this free stuff from the government should be required to make some minimal effort as well."
What a world, where the fat pride movement might be our best defense against Big Brother.

Unless they use immutable AIs to enforce control, the regime will fall through either force or mutation.

More like following the tracks a jeep left in a grass field. True, the particles would disperse sooner or later, but not that soon, I'd say... The ships are quite large, have extremely powerful engines generating tremendous amounts of thrust and are bound to leave behind a considerable radiation trail. I'd wager such trails would be detectable for weeks or months even, if not near a frequently used flight corridor. True, however, that it would apply only for when a ship does a main engine burn to accelerate. When cruising or making minor course changes it will leave behind very little exhaust, if any.

The Sun's light takes a bit less than 5 1/2 hours to reach Pluto. If you assume an exhaust velocity of around 90% the speed of light, it still travels that distance in a little less than 6 hours. The tracks of a jeep are so visible because they modify something that stays in place, but a starship's exhaust is more like a boat wake, always moving, and growing weaker as a result.

[entity2636]

I think exhaust travel at a speed close to the speed of light. So it is all about light speed delay. If you can see it, it's fine, also you are to late.

I agree that the exhaust travels fast and will not stay where emitted, but I do not believe it would travel at a speed close to c. Fast yes, but nowhere near c. Let's consider.

We do not know all the mechanics of the Floater Drive, but we know it uses a matter-antimatter reaction (Type-A fuel is an inert mix of matter and antimatter that stays inert while supercooled but reacts readily when warmed up). The drive is very powerful and very efficient - using inertial dampening and manipulaton of the exhaust stream (that's what the vanes at the ship's tail end are for, and thrust vectoring), a very large portion of the particles' kinetic energy can be harnessed to propel the ship forward instead. Think how tripple expanson steam engines, turbochargers and multistage jet engines obtain their efficiency - instead of the expanding gas doing work in one place and being exhausted still hot, expanding and able to provide energy, it's made to do work multiple times thus a much larger portion of the energy can be utilised.

I see the Floater Drive doing something similar - you have the initial reaction giving some energy and then you manipulate the exhaust particle stream to take most of the particles speed/energy away from them and transfer it into acceleration. If it were not the case and the engine would be a "direct reaction drive" it would consume a lot of fuel and provide very little thrust (like a real life ion drive of Terran fusion drives). Feel free to correct me if I'm wrong or have misinterpreted the drive mechanics.

[Krulle]

action=reaction.
I see the floater drive using the heat of the engine multiple times, but not the kinetic energy of the exhaust.
To get propulsion, you need to expel something in the other direction.
Best acceleration you can get pushing you forward is exhausting something backwards with c.
Until you start deforming local gravity/space.

[SVlad]

Actually, we have all numbers to calculate the exhaust velocity of Loroi engines.
Ship mass = 350000 ton
Fuel mass = 5200 ton
Acceleration = 30G
Time = 100 h
With some math we get an effective exhaust velocity of 7 123 846 154 m/s, that is 23 times faster than speed of light

[Arioch]

Except the point of the Floater drive is to increase the inertia of the propellant, which effectively increases m.

[entity2636]

Actually, we have all numbers to calculate the exhaust velocity of Loroi engines.
Ship mass = 350000 ton
Fuel mass = 5200 ton
Acceleration = 30G
Time = 100 h
With some math we get an effective exhaust velocity of 7 123 846 154 m/s, that is 23 times faster than speed of light

Exactly, and while the math is correct, but result is, how the Germans say, not even wrong because it applies to conventional reaction engines like a chemical rocket - propellant burns, gas expands and exacts, to keep things simple, equal impulse/pressure on the engine mounts and the outside air. Since air resists movement less than the engine, most of the energy is lost (spent to heat the air and move said air away from the rocket). It gets even worse in the vacuum of space.

Except the point of the Floater drive is to increase the inertia of the propellant, which effectively increases m.

Exactly, the drive's inertial dampening component "clamps down" on the exhaust stream, increases the apparent mass of the particles, effectively slowing it down considerably and transferring the delta-E to the ship in the form of thrust. An ideal Floater Drive would leave completely stationary and cold exhaust behind and 100% of the fuel reaction energy would be applied to the ship as thrust because energy = temperature = particles' movement speed.

Kind of reminds me of the firing of a bullet cartridge - fuel burns, gas expands, but since the casing is effectively immovable, all (OK, most) of the gas energy is applied to the bullet making it shoot out of the barrel.

Nothing in real space can achieve or exceed the speed of light because at c the energy required becomes infinite.

*Edit*
The Terran fusion engines on the other hand could be considered conventional reaction engines, except that instead of literally "burning" fuel they use nuclear fusion - think a constant, regulated, contained and directed thermonuclear explosion and the reaction products (Helium-4 and Hydrogen) are directly expelled from the engine providing thrust. This is extremely inefficient compared the the Floater Drive (but still orders of magnitude better than chemical rockets), hence the Terran ships have such massive engines, carry a lot of fuel and are so slow.

[SVlad]

because it applies to conventional reaction engines like a chemical rocket - propellant burns, gas expands and exacts, to keep things simple, equal impulse/pressure on the engine mounts and the outside air. Since air resists movement less than the engine, most of the energy is lost (spent to heat the air and move said air away from the rocket). It gets even worse in the vacuum of space.

Actually, this formulas has nothing to do with pressure, temperature or other chemistry. It's just direct application of law of conservation of momentum.
If engines use some kind of mass effect™ field, they could reach such effective exhaust velocity by temporary increasing mass of exhaust.

[Mr.Tucker]

Where did the Scout ships leave from? Outskirts of human space or inwards? Did they leave simultanously? If I were approaching human space, would there be beacons in adjacent systems (even if said systems lead to nowhere and are not part of any trade route) ?

[entity2636]

Where did the Scout ships leave from? Outskirts of human space or inwards? Did they leave simultanously? If I were approaching human space, would there be beacons in adjacent systems (even if said systems lead to nowhere and are not part of any trade route) ?

For reference, see maps here http://www.well-of-souls.com/outsider/m ... tatic.html and here http://www.well-of-souls.com/outsider/i ... ropped.jpg

They left originally from Sol, Hellas Landing station around Mars which is the TCA Naval base, to be specific, and traveled as a group of 5 ships (4 scouts and one tanker) first towards the border of Terran space - 82 Eridani and from there went rimward (galactic left) toward what was indicated to them by the Orgus to be the front line of the war. Aldebaran is the first star on Loroi charts that could be considered part of Terran territory. Somewhere along the way they split from the tanker and fanned out, where they left the tanker I do not know.

There probably are navigational beacons in border systems explored by terrans, and there are also outposts and stuff in other systems besides the three that have permanent planetary colonies.

[Arioch]

Where did the Scout ships leave from? Outskirts of human space or inwards? Did they leave simultanously? If I were approaching human space, would there be beacons in adjacent systems (even if said systems lead to nowhere and are not part of any trade route) ?

The departure point was Esperanza at 82 Eridani. They would have left in multiple groups, the first including the lead scouts Pellew and Utsumi and the support ship Cavadini, which set up a supply base at the halfway point. The second group included Bellarmine, Matveyev, the transport Prabhu and the frigate Hampton. Both groups rendezvoused at the halfway point to refuel; Hampton returned toward human space to deliver a progress report, and Prabhu and the four scouts continued to the relay point located near Loroi/Umiak space. From the relay point, each of the four scouts took separate paths. The plan called for a third group including Tartakovsky, Galvin and Russell to be sent out for resupply and relay.

The TCA maintains a few buoys in systems they control (for navigational aids and as communication relays); there are not many beyond Esperanza as no regular traffic goes that way, but you would run into a few exploration buoys as you approached 82 Eridani from Loroi/Umiak space.