Everything I know about Jump I learned from MWM

[whartung]

I guess Blackbat242 doesn't believe that.

Well it also depends on the retcon, right?

I mean, if you take for example jump masking and jump shadowing, in the meta game it simply doesn't matter. Ship takes off, ship heads to 100D (like the rules have always said to do), and ship jumps. Depending a bunch of factors (destination system, time of year in both the originating and destination system, orientation of the destination system, particularly if you have a "3D" map, etc.) determines whether the destination is shadowed by either star or or not. If it is, there's a little more travel involved to get there. If not, it's a normal every day jump.

But 99% of the time, the story doesn't really care about the shadowing, it's simply not important. Like waiting for a train or a slow line somewhere, it's usually not germane to the plot, rather it's simply an interesting detail that COULD be leveraged at some other point during play. But if they didn't exist, there's innumerable other mechanisms that can create the same kind of delays or time in space or whatever the jump masking is preventing that day.

Ideally a retcon is adding detail where it was simply implied or glossed over before. But obviously some retcons are worse than others, I just don't think this happens to be one of them.

 

[fusor]

Sure, maybe coming out on the wrong side of the jump shadow adds a few days of travel time to the mainworld in most cases, but it's going to throw a serious spanner in the works for those worlds that orbit giant stars (e.g. Antares).

Antares is an extreme example, but that star has a radius of 5 AU, so its 100D is 1000 AU. If the mainworld is on the other side of that jump shadow, you've got a LONG way to travel at sublight to get there from your jump exit point. Certain jump routes may even only be practical every few hundred years as the planet swings around in its long orbit to the right side of the jump shadow.

 

[aramis]

Sure, maybe coming out on the wrong side of the jump shadow adds a few days of travel time to the mainworld in most cases, but it's going to throw a serious spanner in the works for those worlds that orbit giant stars (e.g. Antares).

Antares is an extreme example, but that star has a radius of 5 AU, so its 100D is 1000 AU. If the mainworld is on the other side of that jump shadow, you've got a LONG way to travel at sublight to get there from your jump exit point. Certain jump routes may even only be practical every few hundred years as the planet swings around in its long orbit to the right side of the jump shadow.

Which makes the implausible=but-canonical habitable worlds all that much beter a subsetting...

 

[fusor]

Which makes the implausible=but-canonical habitable worlds all that much beter a subsetting...

Actually, it makes them even more implausible than they were before.

 

[rancke]

Antares is an extreme example, but that star has a radius of 5 AU, so its 100D is 1000 AU. If the mainworld is on the other side of that jump shadow, you've got a LONG way to travel at sublight to get there from your jump exit point. Certain jump routes may even only be practical every few hundred years as the planet swings around in its long orbit to the right side of the jump shadow.

The maximum extra time that can be added to a trip by jump masking is the time to make an extra jump and refuel. You jump to a place on the far side of the masking jump limit and then jump to the world.


Hans

 

[fusor]

The maximum extra time that can be added to a trip by jump masking is the time to make an extra jump and refuel. You jump to a place on the far side of the masking jump limit and then jump to the world.

How? The jump shadow is in the way, you can't jump across it - that's the whole point of it. You have to travel either by sublight through the shadow to the other side of it and then jump, or you have to travel at a tangent to the bubble until your travel line doesn't intersect it anymore.

And if the world's inside the jump shadow anyway then you can't jump to it, period.

 

[Chaos]

How? The jump shadow is in the way, you can't jump across it - that's the whole point of it. You have to travel either by sublight through the shadow to the other side of it and then jump, or you have to travel at a tangent to the bubble until your travel line doesn't intersect it anymore.

And if the world's inside the jump shadow anyway then you can't jump to it, period.

I think what he means is this:

Say you emerge on the rimward side of the star´s 100d limit, but the mainworld is on the coreward side. You then jump 1 parsec to spinward, and from there you have a direct, unmasked line of jump to the mainworld on the coreward side of the star - or at least to the closest point to the mainworld that is on the surface of the 100d bubble.

 

[rancke]

How? The jump shadow is in the way, you can't jump across it - that's the whole point of it. You have to travel either by sublight through the shadow to the other side of it and then jump, or you have to travel at a tangent to the bubble until your travel line doesn't intersect it anymore.

You jump off to the side rather than directly, following two sides of a triangle.

And if the world's inside the jump shadow anyway then you can't jump to it, period.

Which is why I was speaking of jump masking. Though a world can be both shadowed and masked if it's inside the jump shadow AND on the other side of the star. However, jump shadows that cover worlds in the life zone of a star are only so big. They won't add more than a few days to the trip.


Hans

 

[rancke]

Say you emerge on the rimward side of the star´s 100d limit, but the mainworld is on the coreward side. You then jump 1 parsec to spinward, and from there you have a direct, unmasked line of jump to the mainworld on the coreward side of the star - or at least to the closest point to the mainworld that is on the surface of the 100d bubble.

Except that you jump to spinward from the start, yes.


Hans

 

[Rover]

You could also jump to a point above or below the ecliptic, say one of the solar poles, then it wouldn't matter where the planet was in it's orbit. Space is in 3D and high def, but sadly no dolby thx sound.

R

 

[rancke]

You could also jump to a point above or below the ecliptic, say one of the solar poles, then it wouldn't matter where the planet was in it's orbit. Space is in 3D and high def, but sadly no dolby thx sound.

Chief limitation is that unless you're carrying fuel for a second jump, you have to jump to someplace where you can get refuelled.


Hans

 

[Rover]

Chief limitation is that unless you're carrying fuel for a second jump, you have to jump to someplace where you can get refuelled.


Hans

My point was, if you jump to 100D above the solar north pole, no matter how big the star, no planet will be blocked and you could use your M drive to get to it. There would be no need to make a second jump.

R

 

[rancke]

My point was, if you jump to 100D above the solar north pole, no matter how big the star, no planet will be blocked and you could use your M drive to get to it. There would be no need to make a second jump.

Unless the star is so big that the trip in realspace would take more than 8 days or so, in which case two jumps would be faster. The point I originally made was that the maximum extra time any jump masking could possibly impose was the time it would take to do a second jump. Either you'd be able to do a realspace trip in less than 8 days or you would be able to do two jumps.


Hans

 

[Rover]

Unless the star is so big that the trip in realspace would take more than 8 days or so, in which case two jumps would be faster. The point I originally made was that the maximum extra time any jump masking could possibly impose was the time it would take to do a second jump. Either you'd be able to do a realspace trip in less than 8 days or you would be able to do two jumps.


Hans

Ahh OK I see what you are saying.

Given that 8 days travel at 1g (4 day turn around) is about 750 million miles I still think it would be possible to either jump to a pole, or jump to a point on the far side of a star and travel to the destination in less time, except for the very largest stars, well above 10 solar diameters.

I'm not sure if there would be much reason to jump near a giant star. They will either be very old red giants or very young, very bright white stars. The former are likely to have swollen to a size to swollow thier inner planets and the latter too young to have planets develop at all.

But throwing too much real world science at a game can spoil the fun.

Cheers,
Rover

 

[Dragoner]

My point was, if you jump to 100D above the solar north pole, no matter how big the star, no planet will be blocked and you could use your M drive to get to it. There would be no need to make a second jump.

R

^^^This here is why I don't pay much attention to things like "jump masking" which is totally illogical given space is 3D, not 2D where the masking would only work. I dislike having to explain things that break physical laws, even at just a point of reference. Space is 3D, the maps may look 2D but it's just a map for travel times and is not necessarily accurate, much like polar distortions on a global map.

Three dimensional space:

 

[far-trader]

Now add the orbital planes of the worlds in those star systems

 

[far-trader]

...the maps may look 2D but it's just a map for travel times and is not necessarily accurate, much like polar distortions on a global map.

If only it were that simple

Unfortunately Traveller space is in fact 2D. The maps are not "subway" maps of travel times but actually direct distances between systems. It's a simplified universe not meant to be looked at too hard in most areas.

 

[Dragoner]

If only it were that simple

Unfortunately Traveller space is in fact 2D. The maps are not "subway" maps of travel times but actually direct distances between systems. It's a simplified universe not meant to be looked at too hard in most areas.

Which uncovers the problem of what people are talking about, while I like to see what MWM has said and various articles, it comes down to GM fiat. Otherwise as Rover was talking about, you could just travel in a parabola to reach a destination. The earlier simpler handwavium - 'this is how it works', works best, too much trying to explain it leads down the garden path, I explain Jump with false vacuum and quantum tunneling, which are real world theories and thus harder to argue over; which incidentally large gravitational forces do have an effect. Then to argue 2D versus 3D reality? No.

 

[aramis]

Actually, it makes them even more implausible than they were before.

No, it just makes them not trading with the outside world nearly as much. Hence a good subsetting, even for HT (TL9-15) races with sublight drives only.

Someone moved in, set up shop, and still is there... sure, they don't mind outsiders, but the pace of travel in system means no regular exterior trade... even tho they might have a thriving in-system economy!

A great system to drop a hidden ancient base in - they didn't jump in.

Etc.

 

[Chaos]

No, it just makes them not trading with the outside world nearly as much. Hence a good subsetting, even for HT (TL9-15) races with sublight drives only.

Someone moved in, set up shop, and still is there... sure, they don't mind outsiders, but the pace of travel in system means no regular exterior trade... even tho they might have a thriving in-system economy!

A great system to drop a hidden ancient base in - they didn't jump in.

Etc.

It would also be a good place for a prison colony or other place you´ll want to quarantine - much harder to get into or out of.