Author Topic: Inner Sphere in context  (Read 1545 times)

Thunderbolt

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Inner Sphere in context
« on: 03 October 2017, 02:46:44 »
University of Chicago archives had the following dusty images, of everything within 500pc = 1700ly of Earth, which I annotated to situate the BT Universe in galactic context:


Please do note that the academic image follows the scientific community's galactic coordinate system, which is actually "left handed".  Makes life slightly more difficult, please consider the captions.

Most if the Inner Sphere resides in the vast "Local Bubble", a largely evacuated region of the Interstellar Medium (ISM) wherein the space plasma is hotter and more rarified (less dense) than average.  That makes night skies comparably bright and full of twinkling stars as far as the telescope can see. 

However, the Coreward Periphery of Kurita space extends into the outskirts of the Aquila Rift, a dense molecular cloud whose higher particle density would tend to obscure & redden distant starlight (basically the "sunset effect" on Earth, whereon dust in the atmosphere scatters waning dusk sunlight, preferentially the blue wavelengths, so dimming & reddening the sky).  This would plausibly make night skies on such worlds darker & redder than elsewhere, with "fewer stars all less visible".  Maybe gives writers some ideas for story settings?

Also note that, perfectly plausibly, the "Outworlds Wastes" stretch Spinward into a long "Spinward-stretching finger" of the Local Bubble, as if it were easier to detect and hence reach the viable star systems there.  And one may note that the "Exodus path" of the pre-Clan SLDF wound its way Spinward & Coreward from Kurita space, "around & behind" the dense Aquila Rift cloud.  The Caliban Nebula ("cn" on the map) appears to be a dense "compression" nebula "swept up" by the expanding "Scorpius-Centaurus Shells", i.e. shock-fronts sweeping through the ISM from ancient Supernovae (SNe).  Likewise, the Clan Homeworlds ("CH" on the map) reside in a denser & cooler region of the ISM, on the "farside outskirts" of the Aquila Rift.  Like Coreward Kurita space, the night skies would probably be dimmer & redder than those of the IS, e.g. Earth, further obscuring & hiding the CHs from the IS.

The Hanseatic League & Neuva Castile ("HL" & "nc" on the map) appear to reside within dense molecular clouds.

The SNe shockfront "shells" sweeping outwards from the Sco-Cen association & Orion star-forming regions contain high levels of radioactive Iron-60.  The "Orion shell" may have been generated by an ancient SN several hundred thousand years ago, whose compact neutron star remnant now careens through the galactic disk (from near the Orion star forming region, in a generally Spinward direction) as the Geminga Pulsar ("G" on the map).  More space trivia, maybe even useful :) 
« Last Edit: 03 October 2017, 02:49:56 by Thunderbolt »

Thunderbolt

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Re: Inner Sphere in context
« Reply #1 on: 10 October 2017, 11:58:48 »
IS looking "down" from N galactic pole

Map, 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-spinward

Our 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 core

The 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. 




marauder648

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Re: Inner Sphere in context
« Reply #2 on: 10 October 2017, 16:38:34 »
This is a brilliant layout and thank you for doing this!
Ghost Bears: Cute and cuddly. Until you remember its a BLOODY BEAR!

Thunderbolt

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Re: Inner Sphere in context
« Reply #3 on: 11 October 2017, 06:36:50 »
Thanks for the thanks :)

I've been trusting the outputs of the NED coordinate converter.  Very frustrating if you're not used to the required input format:
  • Generally, you have to set everything to "J2000.0" instead of "B1950.0" -- including the "observation epoch" on the second hand which must be typed manually
  • the required format for starting coordinate values
    • Right Ascension (RA) = "12h 34m 56s" (hours / minutes of arc / seconds of arc)
    • Declination (Dec) = "-78d 54m 32s" (+/- degrees / minutes of arc / seconds of arc, and need to use the regular "-" character, notably not Wikipedia's "−" (emdash??) character
Astronomy helps understand BT universe history, e.g. the hundred year concealment of the Rim World's Republic from the IS... "behind" the blazingly bright Sco-Cen star-forming regions as well as one of the dense shock-front shells emanating from them and bulldozing into the surrounding molecular clouds just "beyond" the peripheral marches of Steiner space.  Just one example, another being that the SL-era OWA deep-periphery settlements extend naturally into the "finger" or "tunnel" jutting spinward from the Local Bubble, also viewable on the maps above, all meshes up :)

abou

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Re: Inner Sphere in context
« Reply #4 on: 12 October 2017, 08:43:05 »
Very cool. I'll need to give it a closer look later when I get the time.

Thunderbolt

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Re: Inner Sphere in context
« Reply #5 on: 18 November 2017, 07:26:07 »
"Global" galactic scale view of the IS and Clan worlds.

Evidently, Alexandr Kerensky led the Exodus all the way to the inner, coreward "edge" of the local "Orion" galactic arm, taking his forces as far as he could until they "ran out of stars".  The dark "Veil of the Protector" nebula, as well as Star Cluster 24 and all of the Clan homeworlds star clusters, reside precisely on the inner coreward "edge" of the Orion arm.  Their night skies must have a spectacularly vacuous view looking towards the Galactic Core.

FYI, Galactic scale magnetic field lines thread through the "arms".  Ignoring possible finer structural details, the ambient background galactic field lines thread through the IS generally from FWL <-> DC almost exactly parallel to the border line through Earth between the LC|FWL - DC|FS.  The average field strength is ~2 nano-Teslas, approximately one ten-thousandth of the strength of Earth's surface field in the early 4th millennium (noticeably weaker and more irregular than it was back in the earliest days of near-Earth space exploration).

Note that the MWG is a "mature" barred spiral galaxy (SBa) with four major & tightly wound arms (Perseus, Norma, Crux-Scutum, Carina-Sagittarius).  Our own local "Orion spur" is an orphaned "arm" fragment approximately 30,000 lyr long, plausibly the result of the next-inner Car-Sag arm over-taking & rotating into & mering with the leading inner span of the Orion arm, approximately 15,000 lyr spinward (and coreward) of our Solar System.  The Car-Sag arm may be "over-rotating-into" the inner "edge" of the Orion arm, which may be "winding onto" the outer "edge" of the Car-Sag arm.  The relative over-take velocity is probably around 30km/s = 0.0001c, such that the "merger zone" might reach our current location in around 15,000,000 years, and the Orion arm may further be finally absorbed & subsumed fully into the Car-Sag arm about 15,000,000 years after that (+30Myr from now).








Thunderbolt

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Re: Inner Sphere in context
« Reply #6 on: 19 November 2017, 02:27:19 »
Far Rimward worlds of TC & MoC with nightsky views of Auriga & Pleiades:




Periphery along LC border with view of Scorpius-Centaurus:






View from Clan-space on extreme Coreward "edge" of the Orion galactic arm w/ Car-Sag arm thousands of light-years in the distance :


marauder648

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Re: Inner Sphere in context
« Reply #7 on: 19 November 2017, 02:40:39 »
Oh wow! This is amazing!
Ghost Bears: Cute and cuddly. Until you remember its a BLOODY BEAR!

Thunderbolt

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Re: Inner Sphere in context
« Reply #8 on: 19 November 2017, 05:23:37 »
thanks, there's 1000pc of perspectives to choose from, makes for many spectacular views  ;D

https://en.wikipedia.org/wiki/RX_J1856.5-3754

In the 31st century AD, neutron star "RX J1856.5-3754" resides at around (0,400) using regular BT IS coordinates, i.e. almost due Coreward 400lyr from Earth... between the "Alleghe" and "New Bergen" systems... not sure if a fast-moving neutron star would have stable jump-points, probably just more trivia

marauder648

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Re: Inner Sphere in context
« Reply #9 on: 19 November 2017, 05:32:11 »
I think that Jumpships would avoid systems with Neutron stars like the plague because ALL THE RADIATION, especially if its a pulsar. 

And the Clan's view of space really is 'staring into the abyss' and the 'end' of the Orion arm looking out into the gap between towards Sagittarius.  Where did you make these? These are superb.
« Last Edit: 19 November 2017, 05:35:57 by marauder648 »
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cpip

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Re: Inner Sphere in context
« Reply #10 on: 19 November 2017, 09:21:46 »
Wow. Those are simply beautiful, and one of those things you just don't think about much; especially for more far-travelling residents of the BTU, the skies look very different from every planet...

Thunderbolt

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Re: Inner Sphere in context
« Reply #11 on: 20 November 2017, 10:32:28 »
Thanks for the thankses :)

Used mostly Adobe Photoshop Creative Studio to cut out far futuristic city-scapes to overlay on APODs and the like.  One of the pictures has a comet... plausibly all IS star systems have meteor showers & comets, unless someone "swept" the systems free of ecliptic dust (?)

Writers have ample material to "flesh out" plot lines with such nuances

Thunderbolt

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Re: Inner Sphere in context
« Reply #12 on: 26 November 2017, 10:57:40 »
I think that Jumpships would avoid systems with Neutron stars like the plague because ALL THE RADIATION, especially if its a pulsar. 

And the Clan's view of space really is 'staring into the abyss' and the 'end' of the Orion arm looking out into the gap between towards Sagittarius.  Where did you make these? These are superb.
Turns out that there may be something of a naming convention, from our Orion arm, the gap between our arm and the next is named after that next arm, e.g. the Clans stare into the "abyss" of the "Carina[-Sagittarius] Gap" whereas far beyond the TC & MC lies the "Perseus Gap or Gulf".  Might be good for a scientifically literate sounding one-liner somewhere.

It does so happen that, in-galactic-plane XY, the Clan homeworlds cluster of stars resembles in size & shape, and aligns precisely on 2D, with the Sagittarius Star Cloud at distance of ~10,000lyr in what "must" be the Crux-Scutum arm.  If terrestrial astronomers cannot observe the Clan homeworlds, then they might reside notably "higher" or "lower" than the galactic midplane and LOS to the SSC.  Viewing the Clan home systems as part of an Open Cluster of related stars could help explain their apparently near uniform marginal habitability... most Open Clusters are young <1Gyr, such that the stars' HZ planets would still be geologically adolescent & volcanically & tectonically super-active (?).  It would also explain their location near a prominent large molecular cloud, the Veil of the Protector, presumably (?) their parent molecular cloud (?).

It may be worth restating that spiral arms are probably material, with most stars and gas clouds residing in them, leaving "abyssal" gaps between them, wherein the galactic magnetic field is hence much more uniform & hence stronger on average. In the arms the galactic field is tangled by the motions of clouds, stars' stellar-wind-blown heliospheres, SN shock waves, etc.  If so, spiral arms are like really big elongate star clusters, with faster moving stars like our Sun tending to be accelerating "forwards and inwards" (spinwards & corewards) relative to the average, and slower moving stars tending to be decelerating "backwards & outwards" (anti-spinwards & rimwards).  Accordingly, the Clan systems are plausibly streaming spinwards & corewards along the inner coreward "edge" of the Orion arm, at something of order 10-20km/s relative to most of the IS.  They may be moving relatively faster than the Pentagon worlds & VoP nebula so as to "shear away from them" accounting for the gaps between them, as well as the elongate structure of the VoP cloud.

A ~1Gyr old Open Cluster would have lost all of its O,B stars to SNe, though some of the compact remnants might remain, possibly even accreting material from smaller companions producing x-ray & gamma-ray bright accretion disks and bipolar jets; the A stars would probably be exiting the Main Sequence of stable H burning and bloating into Red Giants which eventually "bloat themselves apart" in a sort of slow-motion sub-nova producing a so-called (mis-named) "Planetary Nebula[e]" (PN[e]) which gradually disperses leaving a hot white dwarf in the center (the He rich spent core of the former star).  Night-scapes on the Clan worlds might have "Archaean Earth volcanic fires" from below along the horizon, and a hefty scattering of bright red stars and billowing PNe floating in the skies above.  Beyond which would be abyssal darkness out to the Carina-Sagittarius Arm thousands of lyrs in the distance.

marauder648

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Re: Inner Sphere in context
« Reply #13 on: 26 November 2017, 11:43:12 »
I must admit that some of the terminology is loosing me a bit here :S
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cpip

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Re: Inner Sphere in context
« Reply #14 on: 26 November 2017, 14:16:05 »
It may be worth restating that spiral arms are probably material, with most stars and gas clouds residing in them, leaving "abyssal" gaps between them, wherein the galactic magnetic field is hence much more uniform & hence stronger on average. In the arms the galactic field is tangled by the motions of clouds, stars' stellar-wind-blown heliospheres, SN shock waves, etc.  If so, spiral arms are like really big elongate star clusters, with faster moving stars like our Sun tending to be accelerating "forwards and inwards" (spinwards & corewards) relative to the average, and slower moving stars tending to be decelerating "backwards & outwards" (anti-spinwards & rimwards).  Accordingly, the Clan systems are plausibly streaming spinwards & corewards along the inner coreward "edge" of the Orion arm, at something of order 10-20km/s relative to most of the IS.  They may be moving relatively faster than the Pentagon worlds & VoP nebula so as to "shear away from them" accounting for the gaps between them, as well as the elongate structure of the VoP cloud.

So (he asks, showing his astrographic ignorance) does that suggest that over the centuries between the time the SLDF exiles first arrived at the Pentagon Worlds and Operation REVIVAL, the actual distances between the Clan homeworlds and the Inner Sphere changed sufficiently to make navigation even more difficult?

Thunderbolt

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Re: Inner Sphere in context
« Reply #15 on: 28 November 2017, 09:38:17 »
So (he asks, showing his astrographic ignorance) does that suggest that over the centuries between the time the SLDF exiles first arrived at the Pentagon Worlds and Operation REVIVAL, the actual distances between the Clan homeworlds and the Inner Sphere changed sufficiently to make navigation even more difficult?
Well, 30 km/s = 0.0001 c = 1e-4 c...

So star systems flying apart at 30 km/s move 1lyr in 10Kyr...

most relative velocities are of order ~10 km/s, so 1lyr in 30Kyr, or 0.01lyr in 300yr

In extremely round but accurate if imprecise numbers, we're talking 1% of a lyr of distance per century of time or so, think that's about 1000AU / century = 10 AU / year ballpark neighborhood, vaguely like Voyager 1 & 2  :)

these physical FX probably have absolutely no game FX over any amount of game time

I'm just trying to say, that the layout of the Clan star systems & VotP nebula appears to be pretty realistic... the former are farther out on the very inner edge of the Orion arm, and so are probably moving slightly faster spinward & coreward, explaining why the Clan hw / Pentagon w's / VotP nebula appear to be "shearing apart" opening up "gaps" in between.  Moreover, the VotP nebula appears to be "stretched out" into a long linear shape, as the parts of it closer to the faster moving Clan systems may also be moving faster, whereas the "tail end" opposite is moving slower, so that the whole cloud slowly stretches out over "galactic time" and has become fairly long & thin and "stretched out"

It's not unrealistic, 'twould probably be pretty easy to explain if it were actually factually true

Thunderbolt

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Re: Inner Sphere in context
« Reply #16 on: 28 November 2017, 10:03:10 »
Nightscape in "Clan Cluster" (?)

If the Clan homeworlds did reside in a single "Open Cluster" of stars (which, being big, about 200+ lyrs across, would probably also be "mature" ~1 billion years old), that could explain a lot.  Open Clusters form "galactically quickly", so all the stars are about the same age.  And if all of the Clan homeworlds were around a billion years old, they would all be "marginally habitable", because they'd all be "geologically young".  Like the Earth back in the Archaean eon, they'd tend to have dense methane & CO2 tainted atmospheres, and be volcanically & tectonically super-active.

That could imply they also had higher levels of rare, heavy, metals & minerals erupted onto the surface and ultimately available for mining.  You might have a cluster's worth of ideal industrial worlds, whose harsh climates would foster the Clans' martial impetus?  Seems like you could claim Kerensky chose those systems, "at the end of the galaxy" in some sense, for just that very purpose??




Easy

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Re: Inner Sphere in context
« Reply #17 on: 28 November 2017, 11:13:20 »
Oooh, aaaah.

Dragon Cat

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Re: Inner Sphere in context
« Reply #18 on: 28 November 2017, 12:38:00 »
 These are cool the images you’ve created look awesome