I suspect this may have been discussed back when ST: Star Charts first hit the stores, but I'm in want of a memory refresher on the matter. Re-reading the "Sectors" pages, covering the "Subquadrant-Zone-Grid-Quad-Block-Sector" definitions, I'm not sure if this is meant to treat our Galaxy - "halo" region and all - as occupying a cartographic "globe" or "cylinder".
Hi @DEWLine I had to go and look at the relevant pages before posting anything. It looks to me as though the sector system in the Star Charts only covers the disc (or disk) of the Galaxy and nothing else. That means I think it’s “cylinder” not “globe.” That does mean that anything outside the disc isn’t included, but the Galaxy charts show “impenetrable” energy barriers completely surrounding it, so the sector system will cover all the bits of the Galaxy that can be reached. Even a spherical globe wouldn’t include all the “halo” stars unless it extended quite a way beyond the “edge” of the Galactic disc, and a lot of the sectors wouldn’t have much in them. The odd thing to me about this setup is that although the sectors vary in size in the “x” and “y” dimensions, the vertical “z” dimension of a sector will be fixed at 20 light years. I hope this is some use to you. Best wishes, Timon
Well, a pillbox, technically, I guess. The thing is, the sectors are numbered in a fashion that doesn't stem from the "galactic whole" layout, but from the "Earthlings expand into the universe" starting point: low-numbered sectors are centered at Earth rather than the galactic core. Such a setup might better fit a "utilitarian" system where there are no sectors in the halo because Earth doesn't care about the halo much. The geometry of the sector grid is likely to be cylindrical in practice, not spherical, but neither cylinder or sphere coordinates are relevant to the sector numbering system. However, backstage tech manuals suggest that while starships use spherical coordinates in the form of two angles (and on some rare occasions a distance, to give a 3D fix), locations in the Milky Way are given in cylindrical coordinates with two angles and a Z figure relative to a zero centerplane. In onscreen terms, this is neither here nor there, as the only 3D galactic coordinates we get, in "We'll Always Have Paris", are unrecognizable as either angles or linear distances, and (like coordinates in the military world in genera) may be in Starfleet code to begin with. And the Star Charts don't touch upon that issue at all. Timo Saloniemi
And this system is specific to Federation/Starfleet usage, of course. Klingon, Romulan, Cardassian, Tholian, Breen, Gorn, and other "nations" - and several of the various member cultures of the Federation as well - will no doubt have their own systems, translated by authorial fiat for the benefit of us in the viewing/listening/reading audience. In raising the opening question, I suppose I'm thinking ahead to the day on which the Writers in Charge of the Franchise might choose to dismantle at least the Galactic Barrier of "Where No Man..." infamy surrounding the Milky Way's disc.
There's no evidence that the barrier surrounds the entire galaxy, since it's only been encountered in the small part of the galaxy within travel range of Federation space. Indeed, there's evidence that it doesn't surround the whole galaxy or wasn't a permanent feature, since there have been a lot of extragalactic travelers that it didn't seem to have any impact on -- Sylvia and Korob, the "I, Mudd" Andromedan android builders, the Doomsday Machine, the space amoeba from "The Immunity Syndrome," the cloud creature from "One of Our Planets is Missing," V'Ger (implicitly), the Enterprise-D in TNG: "Where No One Has Gone Before," the Nacene from Voyager. (And conjecturally the parasites from "Operation -- Annihilate!," but that was never confirmed.) Indeed, the Enterprise and the Kelvans are the only ones we've ever seen to be affected by the barrier, which argues strongly against it being an all-encompassing or permanent feature of the galaxy. Note also that Samuel A. Peeples, who created the barrier in "Where No Man," also wrote "Beyond the Farthest Star," which showed the Enterprise once again probing beyond the farthest known stars of the galaxy and encountering no barrier of any kind. Which suggests that even Peeples (and D.C. Fontana, who wrote "By Any Other Name" and story-edited TAS) didn't intend the barrier to be permanent or pervasive.
We know in "By Any Other Name" the Feds can send unmanned probes to Andromeda. Warp drives and other systems that got burnt out in "WNMHGB" worked enough in "BAON" to get them out and back in suggesting those systems have been hardened against the barrier. And "Is There In Truth No Beauty" they were fine as long as they crossed it at FTL speeds. For all the other aliens that came in from outside of the galaxy they could've passed through the barrier (or even bypassed it) without being impacted because of different biology and technology. The Kelvans just happened to have systems vulnerable to the barrier. Is the energy barrier in TOS even mentioned in other series?
Adding to the date pile, there is an okudagram from "Aquiel" which mentions the position of a ship being in extragalactic space, so within a hundred years of TOS this region was being explored and charted.
True but in the novels it's stated that it is, and for a good reason. You have to have trans-slipstream or something equivalent type of drive in order to breach it without becoming a psychic jerk.
Alas, it's there in a couple of rather disparate adventures. How come intruders from Andromeda, in a very well known and narrowly defined direction, hit the very same phenomenon that Kirk hit when merely tasked with checking out whether it's possible to fly out of the Milky Way? Then again, we already have to accept that something weird is going on there. The point where Kirk meets the Barrier in "Where No Man" may very well be "sweet" somehow - after all, astronomically against odds, Kirk ran into the recorder marker of the Valiant there and exactly there. Perhaps the same sweetness would draw the Kelvans to the location, too? The counterpoint there is that our heroes can tell some visitors are extragalactic. They do not have any justifiable reason to do so in, say, "Doomsday Machine": such things can never be divined from mere established courses, because the course from my bedroom to my toilet necessarily can be backtracked to outside the galaxy, too. That is, unless the Barrier happens to be right next to the location of the adventure and the trail of the intruder points undeniably at the Barrier. Which tells us something about the spatial relationship of the Barrier and the "most densely populated part of the galaxy" right there... But probably rules out the idea that the Barrier would be a highly local phenomenon, in Federation's terms. Or then the Barrier is the justification for our heroes' outrageous claims in a less (or perhaps more) direct fashion. Perhaps an intruder coming from the outside necessarily always penetrates the (usually harmless) barrier, and this leaves an identifiable residue? So it's a fickle phenomenon - in "Where No Man", crossing by impulse was supposedly done by the Valiant, even though said impulse could previously not fight the magnetic storm that necessitated the crossing. Sounds attractive overall. A bit like the conquest of Antarctica: you have to get lucky with the weather, or learn to read it, in order to get there and back alive. And perhaps you also need a chain of camps and stashes, including the lithium depots Alpha, Beta, Gamma and Delta Vega? Not onscreen. Barriers in general seem to be a TOS phenomenon exclusively: Time, Galactic, Great. And TOS is the era when those all are broken. Perhaps Starfleet just stopped believing in barriers after TOS, recognizing that they would only present an obstacle for the briefest of times between discovery and dismissal - and indeed understanding that ceasing to believe is what defeated the Great Barrier? Timo Saloniemi
Okay, moving along: Using the Sector Grid system...Voyager 74656 spent their first three years in the Delta Quadrant making their way through Grid L9. The whole "Scorpion" mess in the Northwest Passage got them to Grid M7 for the fourth year. We visited M7, M6 and M5 before getting to R1 by the end of Year 5. The process of crossing from R1 to S1 took up the last two years of their misadventures...?
New complication! It turns out that our Galaxy is not exactly a "perfect" disc-shape, per the phys.org article in the link. Thoughts?
Meanwhile, I went and decided to isolate the vertical "stack" of sectors including Vulcan and Andoria using the Stellar Cartography 2nd Edition Federation History map. Check the blue "rectangle" there. I went digging via whitten.org for possible candidates for "Eridani" and "Azati Prime", and I suspect that I am not searching properly. Thoughts, anyone?
The data tapes of recorder marker actually showed that the valiant was swept half a light year out of the galaxy before being thrown clear of the magnetic storm. They then returned through the barrier under their own power. Here's my thoughts on the situation: The Valiant had faster than light drive, but it got knocked out by the magnetic storm. Their impulse engines were still operational, but not strong enough to fight it. The magnetic storm took them out of the galaxy at sublight. That allowed them to pass through the barrier without any damage. It also means the journey out of the galaxy took a long time. Once thrown clear they were able to reactivate their warp engine and return through the barrier. This was a mistake becasue that was when the seven crewmen got zapped. It's also interesting to note that on the Enterprise nobody got zapped by the barrier until after Kirk ordered them to go back. This would mean that the zapping of humans with high ESP rating only happens when entering the galaxy, not exiting.
"Eridani" as a standalone word makes no sense and must be a typo. It's the possessive form of a constellation name and should properly be prefaced by a Greek letter or a number -- e.g. 40 Eridani (Vulcan), Alpha Eridani (Achernar), Epsilon Eridani, etc. But there's no star in Eridanus that makes sense in that position. It's close to where Delta Eri and Tau-1 Eri would show up on that map elevation, but they'd both be further down on the page, roughly where the close parenthesis in "(2120)" is. So I think it's just a mistake.
"Eridani" as in "Eridani D" from Amanda's dialogue in "DSC: Lethe", if memory serves? https://memory-alpha.fandom.com/wiki/Eridani_D Frankly, I'm not sure why the script wouldn't be more specific, either. Perhaps an earlier draft was more precise and the precision was edited out before the scene was filmed. (Heaven knows we've got enough "extra" nebulae, clusters, and such like added onto the map from all the branch series, though...)
I was disappointed by the new Stellar Cartography. For example, they placed the unnamed binary star system far from the Gamma Hydra system. It was stated in the episode that the distance between the two systems was six light years, not the hundreds of light years as shown in the reference work.