Where do these terms originate? The concept of a 100D limit is all through Traveller, of course. But I don't recall seeing these specific terms explained anywhere, though they seem to be used quite a bit on these boards.
"Jump Shadow" and "Jump Mask"
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I don't honestly know. I've been promoting them for many years, but I can't recall the origin. It's possible that it's something I came up with, but I don't think so. My memory is not very good, though, and it was so long ago that I can't be sure.
Hans
The first time I saw them was during the playtesting of GT:Far Trader, where there is a long explanation. I think that counts as the first official publication (that I can recall). I know there were long discussions on the JTAS forums (now deleted) and TML regarding this.
IIRC the terms have been around since CT.
Jump Sahadows at least since the CT Boxed set Tarsus, where it was pointed out as an inherent part of the setting, that Gas Giants and Stars also have 100D limits, or Jump Shadows, and often times the main world of a system will be well within that limit. In the case of Tarsus boxed set, the mainworld lies withing the stars Jump Shadow causing an additional 2 day travel time at 2g to get to and from the jump point and the main world. They even provided nifty travel times tables tables because of this effect.
As for Jump Masking...really, IDK where that originated.
Jump Sahadows at least since the CT Boxed set Tarsus, where it was pointed out as an inherent part of the setting, that Gas Giants and Stars also have 100D limits, or Jump Shadows, and often times the main world of a system will be well within that limit. In the case of Tarsus boxed set, the mainworld lies withing the stars Jump Shadow causing an additional 2 day travel time at 2g to get to and from the jump point and the main world. They even provided nifty travel times tables tables because of this effect.
As for Jump Masking...really, IDK where that originated.
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When did that issue come out? I recall seeing the concept of jump limits relative to stars in another game published in 1980
The concept of jump shadowing, yes, and Marc Miller says that he intended jump masking too from the very beginning, but there's not a hint of it reflected in rules nor adventures for many years.
Hans
I checked GURPS Traveller: Far Trader, and there is a nice section on "Jump Masking," but I don't believe the term "Jump Shadow" is used anywhere.
salochin999
SOC-13
A side issue but if - like me - you like to use rolled star ports even if they don't seem to make sense with the world stats then an extreme jump shadow could be one of the reasons a system that ought to have a better star port doesn't i.e. the extra costs encourage self-sufficiency.
The thing is, when you look at the types of systems where jump masking and shadows could be a problem, the ones where this would be an extreme problem are also the very rare giant and supergiant type stars.
The most common stars that have 100D outside the habitable zones are the main sequence M stars. In T5 the habitable orbit is 0 (making all these worlds tide-locked), but the 100D limit is inside orbit 1. A pain, but nothing that would really screw up logistics.
The most common stars that have 100D outside the habitable zones are the main sequence M stars. In T5 the habitable orbit is 0 (making all these worlds tide-locked), but the 100D limit is inside orbit 1. A pain, but nothing that would really screw up logistics.
Well, those and the third or more of stars that are type K and M main sequence stars.
Wait, in T5 the solar jump limit for Class M V stars is inside orbit 0?!?
Hans
Lycanorukke
SOC-13
It depends on the star (pg 438)
M0 V: 100d = Orbit 1
M5 V: 100d = Orbit 0
M9 V: 100d = Inside orbit 0
In all cases for M V stars, the Hab zone is orbit 0, so for M5-M9 you only have to worry about the planetary limit.
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