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placement in space: where are the off-world homeworlds?
06-28-2014, 12:22 AM
Supertemps says that "Rynkar is located on the opposite side of the Milky Way from Earth", so we probably don't need to figure out its location more specifically than that. My brain, however, has found itself doing the math on the location of the Confederation home cluster, and in the process, I started trying to figure out where Myrr's primary is.
I actually narrowed the latter down first. P.IST36 says it's "ten light-years from ours, toward the edge of the galaxy." In OTL, there are only five stars at that distance (at least according to Wikipedia), and only one that's on the side of our sky away from the center of the galaxy: e Eridani.
Identifying the Confederation cluster is a little harder; Bob says only that it's "over a thousand light-years away, towards the center of the galaxy" (p.IST35). Getting more specific than that would require knowing how much over a thousand light-years, and whether it's a globular cluster or just an open cluster. (I picked up the terms from the 4e version of GURPS Space, then went to Wikipedia to find out what the known ones are. Then again, I'm assuming it is one of the known ones, if only because I have trouble believing that many stars could hide from our sight.) If it's a globular cluster, the nearest one of those in the right general direction is M4, a "mere" 7200ly away. If it's an open cluster, there are several in the right direction at the right minimum range. (I'm tickled by M23 myself, but that's probably over-egging the beer...)
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Quote:I actually narrowed the latter down first. P.IST36 says it's "ten light-years from ours, toward the edge of the galaxy." In OTL, there are only five stars at that distance (at least according to Wikipedia), and only one that's on the side of our sky away from the center of the galaxy: e Eridani.
Lucky us - e Eridani has a NASA/JPL page with public-domain artwork. The "grunt work" of describing the system has already been done for us.
--
Rob Kelk
"Governments have no right to question the loyalty of those who oppose
them. Adversaries remain citizens of the same state, common subjects of
the same sovereign, servants of the same law."
- Michael Ignatieff, addressing Stanford University in 2012
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... I don't know whether to be intrigued or frightened by the work and conclusions produced by descriptive text I can pretty much assure you I pulled out of thin air at the time I wrote the passages. in question.
I would comment that when I said that the Confederation cluster was "over a thousand light years away", I almost certainly meant "a thousand plus a little", probably best quantified as "1000-1150 or so light years". Being slightly buzzed from the first bottle of beer from my latest batch of homebrew (7% alcohol! yay!) plus more than a little drowsy at the moment even without the beer, I haven't tried to dig through the Wikipedia page you linked to, so I don't know if I just gave you a bullseye or left you with nothing.
-- Bob
---------
Then the horns kicked in...
...and my shoes began to squeak.
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I decided to take the figures as stated and see where they led me. Self-imposed challenges are, after all, the most fun kind.
At 1075 ly ± 75, we have one target that might be within the range -- the Ptolemy Cluster, somewhere between 945 and 1011 light years from Earth -- and another that definitely is -- IC 4665, whose distance of 352 parsecs from Earth actually translates to about 1148 ly, not 1400 as its Wikipedia page has it. I'm leaning toward the Index Catalogue one, but if you'd prefer M7, I'll bow to your judgment, even if it's currently impaired.
And congratulations on the brewing! My dad had to give it up shortly after we moved from Mississippi to central PA (he didn't actually finish his last batch or formally abandon it; Bilious only knows what it's turned into by now).
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Update: I took the habitability data on Myrr and Nea!son^ma from IST1 and ran it through the world-building steps in chapters 4 and 5 of Fourth Edition GURPS Space, plugging Epsilon Eridani's characteristics (mass, luminosity and so on) into the "Advanced Worldbuilding" portion of the process, and worked out that Myrr has to be orbiting at about 0.54 AU to have the stated temperatures. Also, Nea!son^ma's primary is probably a young G1, unless it's in NGC 6633 (the odd man out in terms of distance -- 375 pc actually equates to around 1200ly -- but in the right direction and old enough to support older stars), in which case it's probably a G4 which Nea!son^ma orbits at 0.88 AU.
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Mamorien Wrote:Update: I took the habitability data on Myrr and Nea!son^ma from IST1 and ran it through the world-building steps in chapters 4 and 5 of Fourth Edition GURPS Space, plugging Epsilon Eridani's characteristics (mass, luminosity and so on) into the "Advanced Worldbuilding" portion of the process, and worked out that Myrr has to be orbiting at about 0.54 AU to have the stated temperatures. ... Which puts it closer to the star than anything JPL has discovered in orbit around e Eridani - but that can be handwaved away by the fact that there are two asteroid belts in the system, making observations difficult. ( http://www.spitzer.caltech.edu/images/1 ... the-Making]More NASA/JPL artwork.)
We are being astronomically accurate where possible, right?
Hmmmmm... two asteroid belts in the system... and it's a relatively young system, too... this might mean Myrr sees many close-approach asteroids, which would colour the Meeranon "racial personality."
--
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robkelk Wrote:but that can be handwaved away by the fact that there are two asteroid belts in the system, making observations difficult. (More NASA/JPL artwork.)
We are being astronomically accurate where possible, right?
I was certainly trying to be. Also, superscience telescopes may have better resolution.
Quote:Hmmmmm... two asteroid belts in the system... and it's a relatively young system, too... this might mean Myrr sees many close-approach asteroids, which would colour the Meeranon "racial personality."
Very good point. The roll for number of moons in GURPS Space is modified far enough down by Myrr's proximity to e Eridani that they're not even likely to have moonlets, leading me to wonder how we can justify them even developing a space program. Frequent asteroid approaches might have provided just the prompting they needed.
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Preliminary math indicates to me that there are probably three orbits between Myrr and the inner limit imposed by e Eri's size, two between Myrr and the asteroid belt that's so close to e Eri b, and two more between e Eri b and the outer asteroid belt. I haven't yet rolled to determine, or arbitrarily decided, what fills those orbits, except that the outer ones are likely to have gas giants.
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Something I've been trying to remember to ask for a while: On p.IST32, Nea!son^ma is said to have "a lower partial pressure of oxygen than Terran normal". Is it low enough to qualify as a low-oxygen marginal atmosphere as per p.80 of Fourth Edition GURPS Space? If so, I think we should give the Kyz (or at least Touchstone) the Pressure-Tolerant Lungs perk from p.211 of GURPS Bio-Tech to reflect that Earth's atmosphere doesn't seem to affect her in the ways outlined in the "High Oxygen" section of p.S80.
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