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CT Only: Jump Drive Primer

OldSalt

SOC-7
This is my jump driver primer to explain how it works and its implications for my players. I'd appreciate comments to polish it. Note it includes my own thoughts on how jump drive works.

Jump drive is the means of travel and communication in the Traveller universe as it provides a viable means of interstella transit.

It works by week-long transitions though jump space, regardless of the distance travelled in real space.▮ Including the time to travel to and from suitable jump points, this makes each jump generally just under 2 weeks.

Using the gravitational wells of the origin and destination stars as reference, a navigator plots a course referencing astonomical charts and jump space mathmatics.▮ This specialised mathematics is the reason why Imperial star charts seem flat, as they reflect the practicalities of jump space travel rather than astronomy.

Jump space is a place for lonely, week long travel, where space as we know it, is limited to a sphere around the travelling space vessel.

Jump drives are rated from 1 to 6 and this rates the jump distance each ship can travel in a week.▮ Higher levels of technology can produce higher rated jump drives.

Because jump drive is far faster than any known kind of relativistic travel, this is means by which news travels and therefore news can travel slowly.▮

This is the reason for the Imperium's semi-feudal structure as nobles coordinate strategy locally, having to act independently until further directions from superiors can be received.
 
This is my jump driver primer to explain how it works and its implications for my players. I'd appreciate comments to polish it. Note it includes my own thoughts on how jump drive works.

Using the gravitational wells of the origin and destination stars as reference, a navigator plots a course referencing astonomical charts and jump space mathmatics.▮ This specialised mathematics is the reason why Imperial star charts seem flat, as they reflect the practicalities of jump space travel rather than astronomy.

I like this.

Personally I also explain J1 through J6 (and misjumps) as being a equated to a "depth" of the jumpspace which move the ship along at different "speeds", which helps explain why all jumps take a week despite covering different distances.

D.
 
I like this.

Personally I also explain J1 through J6 (and misjumps) as being a equated to a "depth" of the jumpspace which move the ship along at different "speeds", which helps explain why all jumps take a week despite covering different distances.

D.

I think of it differently, more like a combination of the computing problem of handling all space/jumpspace conditions over more parsecs, more entry power to cover the greater distance re: the fuel cost (a massive muon-catalyzed fusion pulse), and a greater understanding of jumpspace physics.
 
I think of it differently, more like a combination of the computing problem of handling all space/jumpspace conditions over more parsecs, more entry power to cover the greater distance re: the fuel cost (a massive muon-catalyzed fusion pulse), and a greater understanding of jumpspace physics.

I'm prone to say higher rated jump drive ships are projecting deeper in jump space, as much as you can in a medium where distance has no meaning outside your ship's jump bubble.

This is why the transit time is the same.

Additionally I have suspected that some of the emissions from the jump bubble escape back to standard space/time via the original jump point, leaving a signature that sensors might pick up. One that a sufficiently high enough tech level might be able to process in order to deduce the destination.
 
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I explain it as the ship opens a gravity well in Nth dimensional space. The strength of the drive determines the depth of the well opened, and this is projected ahead of the ship. J6 (about 24 light years) is the most you can "stretch" the gravity well, thus limiting the distance you can go in a single jump. Time is a constant in this equation / process so however far you jump it takes a week.

The ship is "pulled" (or "falls") into the well, and emerges at the singularity point at the other end a week later. The variances in time and distance are due to the presence of stray gravity sources (eg., micro-gravity) and imperfections in the jump systems of ships.

Thus, you have to be clear of any large gravity field. Only micro-gravity can be present when you jump as this is taken into account as a universal constant in the navigation program. A highly skilled navigator can tweak the jump data to improve the accuracy over canned navigation programs. A good engineer can compensate for minor variances in the plant and jump grid improving accuracy too. This is how they can avoid a mis-jump if within 100 diameters of a planet / when within a stronger gravity field and prevent one more of the time.
Low skill crews are forced to rely on the available navigation programs and hope the plant works the way it's supposed to. I would allow players to buy a better navigation program (lots more credits) if they wanted to, as that seems reasonable. I'd also suspect that bigger companies and shipping firms have their own, private, versions with better navigation data for the routes their ships move along.

In addition, the ship should be stationary when jumping as momentum makes it much harder to accurately open a well for a jump. It can be done, but increases the possibility you'll end up not accurately emerging at the other end. Momentum is also conserved. This too can be a problem as the vector on entry is the vector on exit and the exit vector may be in a very inconvenient direction, like away from your desired course of travel, etc.

That's my version.
 
And a respectable version it is too.

I might adopt killing the relative inertia along with dimming the light, as traditions that may or may not be necessary.
 
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