IS looking "down" from N galactic poleMap, scaled and reflected, of the IS situated in the "Local Bubble", as viewed from high "above" the plane of the galactic disk.
Shading shows "column density" of space gas & dust "projected" onto the disk plane of the Sun's orbit around the galactic center. "Vertical" (z-axis) information is "projected out". The figure includes the
UMa (trivia: most of the stars of the Big Dipper) and Hyades in
CC space, as well as the (projections of the) spherical "shock front" shells sweeping outward from the Scorpius-Centaurus star-forming regions arcing around the periphery of the
LC:
possible game FX: the high-density (10x the Local Bubble average, ~0.5/cm3) of gas & dust swept up into the fast-moving shock fronts (~100km/s relative velocity) is "clumpy" with dense "cloud cores" 1-100AU across which can & do overwhelm stars' winds to penetrate into their inner planetary systems, without being disrupted or dispersed. There they can & evidently have obscured the central star, and deposited material onto inner planets, for hours to days to weeks or more.
A high-velocity core passing through an IS star system would resemble the 21st century movie Gravity, acting like a giant shotgun blasting planets, moons, travelling dropships, and recharging jumpships with high-velocity microscopic debris. This could affect all manner of orbital & space-transport-dependent BT operations, grounding dropships and endangering all space-based assets, for protracted periods.
This could account for why the IS, more than less, appears to abut the boundaries of the Local Bubble, without penetrating past its walls. First, the higher densities of dust & gas beyond obscure observations of any star systems secreted amidst the same, making measurement of distances & determinations of precise locations difficult. Moreover, the possible presence of transient mass anomalies near those stars further complicates Jump-point positioning & Hyperspace Jump calculations. As above, but with an added
contour, showing the intersection of the "wall" of the "Local Bubble" (where the density of space gas & dust increases sharply) with the Sun's orbital plane. Almost invariably, anywhere & everywhere where the
shading extends "Sun-ward" beyond & inside of the
contour, represents concentrations of space gas & dust
below the plane of the picture:
IS looking "forward" along Sun's direction of motion from anti-spinwardOur Local Bubble forms a "chimney" penetrating through the galactic disk and opening out into the galactic halo both "above" and "below" the disk. The Local Chimney angles "up and away" from the galactic center (towards the N galactic pole [+z] and rimward [-x]). From the anti-spinward vantage point, the
LC &
FWL are visible, coreward (+x) and rimward (-x), respectively. Their depicted radius is the usual & customary
400 lyr ~ 122 pc.
As above, the
shading shows projected column density, and the contour shows the intersection of the Local Bubble wall with the plane (x,z) of the picture. On the left side of the image, wherever the
shading extends beyond the
contour represents material "beyond" the plane of the picture,
i.e. farther spinward (y>0).
Crude sketch of the "verticality" of the IS, to swiftly suggest the extra "degree of freedom" available to writers, GMs,
et al:
possible game FX: Adding another axis ("z") along which IS star systems could have differing positions would tend to increase the distance between them. "Stretching" the IS "vertically" would make the IS rather sparsely populated, such that inhabited star systems are few & far between.
However, as of the 31st-32nd centuries, only one in a thousand star systems are settled. So, in amongst the systems typically displayed on IS star charts, drift a thousand times as many others, whose otherwise typical stars do not happen to harbor viable worlds suitable for settlement.
This suggests the notion of "transit systems", non-inhabited IS star systems used as "KF-drive recharging stations" en route between inhabited ones. Notable Jumpship pilots may have accumulated centuries-worth of Jump-point data for their favorite selection of systems, as well as Hyperspace Jump calculations for transits between them.
Some of those transit systems may harbor "marginally habitable" worlds which once were tentatively settled during the heyday of the Star League, but whose colonies collapsed in the centuries since. Such sites could conceal Lostech.
Note that Periphery powers probably extend as far in the "vertical" direction (z) as they do in the primary galactic disk plane. If so, even major Periphery powers, like the Taurian Concordant (depicted in dark orange) and Magistropy of Cassiopeia (depicted in light green), would be dwarfed by the major IS states. Note, too, that both the Taurian Concordant & Magistropy of Cassiopeia would have breathtakingly beautiful night skies, by virtue of being located near to the panoply of OB star-forming regions in Taurus, Auriga, Perseus & Cassiopeia. IS looking "outward" from the galactic coreThe Local Bubble is actually more like a "crater" which narrows in the "downward" direction,
i.e. towards the S galactic pole (-z). Here, viewed from the galactic core (or Clan homeworlds), the
LC &
DC are visible, anti-spinward & spinward, respectively.