Conlang relay [relocated] (aka "The Cursed Relay")

[CatDoom]

Interesting. The rising of Venus was considered tremendously important in Mesoamerican culture, in which the planet seems to have been thought of as battling and defeating the sun and moon, presumably because it appears during the transition from day to night and persists for a short time after sunset and sunrise. The Maya were able to calculate the heliacal risings of Venus with great accuracy, and planned coronations and wars to coincide with them. They apparently composed accurate tables charting the movements of Mercury and Mars as well, and some rather enigmatic cycles described in Maya calenders have tentatively been linked to Jupiter's synodic cycle. They appear to have been at least aware of Saturn as well.

[the duke of nuke]

That's rather cool! On that note, I've done some more calculations on your example and found that the chthonian planet #1 would be as bright as #2 or Venus (if it's as reflective as Mercury - it could be brighter). OTOH it'd be less than 9 degrees from the sun at its closest, and the sun is nearly half a degree across already. It'd be visible only very briefly at dawn and dusk and eclipses... but quite noticeable then.

An interesting possibility...

[CatDoom]

Ooh... we could call it "the sun's mysterious partner." I like it.

[Lyhoko Leaci]

Using the calculator I made when dealing with the CCC solar system:

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1: Magnitude: -6.0 Albedo: 0.09 (Mercury-like)
2: Magnitude: -5.4 Albedo: 0.76 (Venus-like)
3: Magnitude: -0.6 Albedo: 0.11 (Mercury-like)
5: Magnitude:  7.4 Albedo: 0.18 (Mercury-like, but a bit brighter)
6: Magnitude: -0.4 Albedo: 0.46 (partially icy rock)
7: Magnitude:  3.5 Albedo: 0.74 (iceball)
8: Magnitude: -0.5 Albedo: 0.35 (gas giant)
9: Magnitude:  2.0 Albedo: 0.33 (gas giant)
10: Magnitude: 6.9 Albedo: 0.31 (gas giant)
11: Magnitude: 8.4 Albedo: 0.29 (gas giant)

The comments are in relation to the albedos.

Tol 1 and 2 are very bright.
Tol 3, 6 and 8 are reasonably bright, but not more so than the brightest star.
Tol 7 and 9 are dim, but visible.
Tol 5, 10 and 11 aren't visible to the naked eye. (And Tol 5 is small enough that it might not even be circular.)
The size of Tol 8, 9, 10 and 11 aren't given in much detail, so their brightness could vary a bit, and Akana was assumed to have the same radius as Earth. (Which, as all the other planet's sizes are given in multiples of Akana's size, could also change things.)

For a main sequence star of 1.0265xSun masses and a brightness of 1.096xSuns, Akana needs to orbit at about 1.043AU to have a year length of 384.1 days, assuming Earth days and Akana days (or rotation period, at least) to be the same. At this point, Akana gets 0.7% more sunlight than the Earth.

[CatDoom]

Hmm... I knew the math I was using was a little rough, but 0.7% more sunlight seems like it might be a bit much. Then again, I suppose surface temperature is influenced enough by atmospheric factors that we could fudge things to where we need them.

[Lyhoko Leaci]

A 1.024 solar mass star with a brightness of 1.087xSuns and an orbital radius of about 1.04234AU gets the correct number of days and the same amount of sunlight as the Earth. Of course, this then messes up the year lengths of the other planets a bit, too. Then again, they were messed up to begin with, as they appear to assume a star mass of only 1 solar mass...

The change in brightness does not significantly affect the planet brightnesses. (Well, Tol 5 now as a magnitude of 7.5, but other than that, nothing changes)

[the duke of nuke]

My calculations came out with Akana's sun (Tol) being 1.039 solar masses, 1.079 solar luminosity, and 1.020 solar diameter based on the same "line" that our Sun occupies in the main sequence (and a SMA of 1.047 AU). But mass and luminosity are not entirely dependent on each other, so we shouldn't worry too much about all the decimal places in my view

The apparent magnitude formulae I used should be accurate, but Lyhoko, I'd like to see your methods too! I used the formula here and the equation H=15.618-5log(D)-2.5log(pv) where D is the diameter in kilometres and pv is the visual Bond albedo.

[Lyhoko Leaci]

I used equations from Bricka's site:

For planets that are closer:
10*log(149597870.7)-2.5*log(L)-67.647-2.5*log(r1*r2*a)+5*log((sqrt(d1^2-d2^2+0.00001))*d2)+0.752
For planets that are farther away:
10*log(149597870.7)-2.5*log(L)-67.647-2.5*log(r1*r2*a)+5*log((d2-d1+0.00001)*d2)

10*log(149597870.7)-2.5*log(L)-67.647 is for "initializing" the equation, L is the luminosity of the star.
2.5*log(r1*r2*a) is for the brightness component of the planet, r1 and r2 are the equatorial and polar radius, a is the albedo
5*log((x)*d2) is for the dimming of the planet due to distance between the planet and the viewer, d1 is the distance from the viewer planet to the star, d2 is the distance from the viewed planet to the star, and x is the distance between the two planets, the 0.00001 is simply a term to prevent messes, and should be negligible in other cases
the 0.752 in the first case is to adjust for a phase angle of 90 degrees.

Also, my values are going to be different from yours even if we used the same equations, simply as I have no idea what you have put for the albedos of the planets.

[CatDoom]

My calculations were assuming a stellar mass of 1 sun; I wasn't certain what mass DukeofNuke was using to calculate Akana's orbital distance at 1.047 AU. In any event, I knew that my numbers were going to be off, so that's not really a big deal as far as I'm concerned.

[Basilius]

Either way some things are apparent about the moon.
- In order to cause total eclipses, the moon must be 4497 km across (4466 km for the latter case) at a bare minimum, probably more like 5000 km. This puts it in the league of Solar System objects like Callisto (4820 km), Mercury (4879 km), Titan (5152 km), and Ganymede (5262 km).
- If we went for an example of 5000 km diameter, and a density of 3300 g/cc like our own moon, it would have a mass of 0.036 times the Earth (or Akana), very close to three times the mass of our moon. (Yes, Callisto, Titan, and Ganymede are much less dense, but they're icy. Mercury is much more dense because it's largely iron. I think Earth's Moon, Io, and possibly Europa and Mars are better models for a mostly rocky body, indicating a density between 3000 and 4000 g/cc.)
- Tidal forces would be strong. This is mitigated by the greater distance to the moon (inverse squares means that the relative strength of gravitational attraction compared to our Earth-Moon system is 60% for the first scenario and 64% for the second). However, even in the first scenario and with a 0.036 Earth-mass moon, tidal forces would be 80% greater than those exerted on Earth by our Moon.

This caused an exacerbation of my paranoia. I mean, 80% looks like a lot.

That is, this dumb guy I call "me" just feels that he can't immediately foresee even in most vague way what kind of consequencies such a difference may entail. Volcanic activity? Shapes of coastlines? I can't even guess.

(Perhaps more sensibly: won't this stronger gravitational attraction imply a much faster evolution towards mutual tidal lock - and, therefore, suggest that Akana with its 22~24 h day duration must be a much younger planet than Earth?)

I must ask my doctor if a less dense moon can be advised as a remedy to my condition =)

Cool stuff anyway, folks. Poast moar :)

[CatDoom]

Perhaps more sensibly: won't this stronger gravitational attraction imply a much faster evolution towards mutual tidal lock - and, therefore, suggest that Akana with its 22~24 h day duration must be a much younger planet than Earth?)

It's been my impression that the speed at which planets rotate can vary considerably even under similar conditions, so maybe Akana was just spinning faster than earth from the get go, and tidal braking has already slowed it down to an earthlike speed.

[the duke of nuke]

Cedh and I had a bit of a chat about this on IRC:

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<duke> While you're online, what are your thoughts on the current Akana astronomy discussion?
<cedh> I don't know much about astronomy, but it's great to see this topic being discussed
<cedh> I think it'd be great to have a system with the following properties:
<cedh> - all parameters relating to Akana very similar but not identical to Earth
<cedh> (apart from those with different set values, e.g. year length in Akana days)
<cedh> (but e.g. day length should be somewhere between 22.5 and 23.9 Earth hours)
<cedh> - the moon may need to be comparably smaller because otherwise it'd have too heavy tidal effects
<cedh> - but in order to make up for that, let's have several interesting planets
<cedh> the two very bright inner planets are cool
<cedh> maybe one or two of the outer ones should be fairly big and bright too
<duke> Mm, makes sense.
<cedh> basically, I like where the discussion is going but would like to keep things not too different from what we know about our own system
<duke> I'm inclined to agree.
<cedh> cool
<duke> The reason I gave a large likely value for the size of the moon was for eclipses - if it is smaller, all eclipses will be partial or annular, but that's not a major blow.
<duke> Tides that strong would certainly change the state of the coasts significantly :P
<cedh> I agree, having no full eclipses is a minor trade-off
<cedh> *only a minor...
<duke> Yeah.  The Anaitists can still have their occasional panics at the sun being attacked by Aiunaka :)

We seem to be all agreed (speaking to Basilius, CatDoom, and Cedh especially here) that the objective is the same - nothing too different from Earth, but still interesting. To help us reach this I propose the following:
- Akana is the same size and mass as the Earth and receives the same amount of energy from its sun.
- The Akanaran year is just slightly longer than ours in absolute terms but the day is slightly shorter (to make the timekeeping close to Earth standards).
- The Akanaran sun is very similar to the sun - perhaps marginally brighter and more massive.
- The moon is about 25% further out than ours (to keep the month consistent with the year), and not much more than twice massive (to keep tides close to Earth levels). This means that there will be no total eclipses of the sun, allowing for realistic lunar density.
- There are two or three inner planets, at least two of which are bright and clearly visible from Akana.
- There are some outer planets, at least two of which are bright and clearly visible from Akana.


A suggested set of parameters for Akana and its sun and moon:

Mass of sun (Tol): 1.017 solar masses
Luminosity of sun: 1.041 solar
Diameter of sun: 1.008 solar

Orbital distance of Akana: 1.020 AU
Year: 1.022 Earth years (32252877 seconds exactly)
Synodic day: 23 hours 19 minutes 30 seconds (0.972 Earth days, or 83970 seconds exactly)
Apparent diameter of sun from Akana: 0.527 degrees of arc (0.988 times ours)

Orbital distance of moon: 486803 km
Synodic month: 3775291.2 seconds exactly
Sidereal month: 3379689 seconds
Mass of moon: 0.023671 Earth masses (1.925 times Luna, slightly less than Titan)
Diameter of moon: 4424 km (1.273 times Luna)
Density of moon: 3120.2 kg/cu.m (intermediate between Europa and Luna)
Tidal force: 1.200 times ours
Apparent diameter of moon from Akana: 0.521 degrees of arc (0.988 times sun from Akana, so up to 97.5% of the sun's area may be covered in an eclipse)

This gives a very slightly longer year than ours, a very slightly shorter day, slightly stronger tides, marginally smaller solar and lunar discs, and not-quite-total solar eclipses. Took me about an hour to work out, but I think it fulfills all of the requirements, and the other planets can be worked out independent of this. Let me know what you think.

[Novilin]

I guess I'm in if this can be explained a bit more

[Lyhoko Leaci]

If Akana and its moon have slightly eccentric orbits, then a total solar eclipse might still be possible, if all three line up when Akana is at its farthest point from Tol and it's moon is at its closest point. (This would mean that any eclipses at other points would at most be just annular, and would cover less than 97.5% of Tol at certain points) This would require the orbits to be aligned just right, though, and may be too much to bother with if you don't mind not having total solar eclipses.

[the duke of nuke]

Lyhoko Leaci: That's an excellent point, and a caution against my oversimplification.

As the orbital period depends only on the semi-major axis and the size of the central body, it wouldn't need any new calculations of orbital time, masses, etc. Let's have an Akanaran eccentricity of e=0.0093, intermediate between Venus and Earth, and a lunar eccentricity of e=0.0335, a little less than Luna. With the parameters I posted above, we have:
- Akanaran distance between 0.988 AU and 1.056 AU, meaning the sun (Tol) varies between 0.540° and 0.505°.
- Lunar distance between 470495.1 km and 503110.9 km, so the moon varies between 0.539° and 0.504°.
That's plenty of overlap to allow for total eclipses. Thanks for bringing that up!


Novilin: Hi, and welcome!
Akana's a collaborative conworlding project that's been running for about nine years, and has accumulated a lot of material. I recommend you have a look at our FAQ page for a quick overview.
This thread started out as the Second Reconstruction Relay thread - the relay itself is very slowly drawing to a close, as the languages involved have mostly got grammatical sketches, and reconstruction work is effectively finished on Team 2 and in the early stages on Team 1. Right now the discussion here is about fleshing out the star system that Akana occupies, but other work on the project continues as we speak.

What are you personally interested in about the conworld? Our main focus is on diachronic language development, but there is plenty of opportunity for other developments of various types. The history and languages established at the moment run through from the lower neolithic up to a vaguely mediaeval period and spread over three continents, so there is no shortage of material to build on.

[Neon Fox]

Well, I've just discovered that I can't edit pages on the Akana Wiki from this computer; I can look at them and open pages for editing, but hitting the Save button triggers a block...which I discovered at the cost of a couple of very nice words that I will now have to reconstruct when I get home. My good intentions of actually doing something with PNE again are thus foiled, or at least put a bit on hold, alas.

[Cedh]

Well, I've just discovered that I can't edit pages on the Akana Wiki from this computer; I can look at them and open pages for editing, but hitting the Save button triggers a block...which I discovered at the cost of a couple of very nice words that I will now have to reconstruct when I get home. My good intentions of actually doing something with PNE again are thus foiled, or at least put a bit on hold, alas.

Can you tell me what kind of block you got? No response? Server error? No editing rights? Something else?

[Neon Fox]

Well, I've just discovered that I can't edit pages on the Akana Wiki from this computer; I can look at them and open pages for editing, but hitting the Save button triggers a block...which I discovered at the cost of a couple of very nice words that I will now have to reconstruct when I get home. My good intentions of actually doing something with PNE again are thus foiled, or at least put a bit on hold, alas.

Can you tell me what kind of block you got? No response? Server error? No editing rights? Something else?

The local firewall; nothing you can do from your end. Basically my IT department telling me that I am not to waste my time on such frivolous pursuits.

[the duke of nuke]

I'm glad to see more on PNE - let's hope the firewall doesn't hamper you too much.

[Neon Fox]

I'm glad to see more on PNE - let's hope the firewall doesn't hamper you too much.

Well, thanks. I'm hoping it looks cool when it's a little more fleshed out.

I've been meaning to ask, is your icon your SCA arms or something? (Per fess wavy argent and azure, in chief an annulet rouge, oh god I am a geek.)

[the duke of nuke]

Ah, good question! The answer is "no" - I'm not in the SCA - although I am a larper and a member of my university's Heraldic & Genealogical Society... It's actually the arms of Meduzís, part of my own (much neglected) conworld.

Though that does remind me of something: I wonder if any of us who do, or have contacts in, SCA or LARP or similar could organise a few photos to illustrate the wiki...

[Neon Fox]

I wonder if any of us who do, or have contacts in, SCA or LARP or similar could organise a few photos to illustrate the wiki...

I know naught of LARP, but in the SCA your big problem would be getting enough people in proper costume, whatever "proper" happened to be. For every person in impeccable Elizabethan/Viking/Roman/whatever, there are twelve in t-tunic and sweatpants--and Akana clothing wouldn't be exactly like that impeccable toga anyway.

You might do OK with just pics of artifacts, though. Knives we got.

[Pogostick Man]

Though that does remind me of something: I wonder if any of us who do, or have contacts in, SCA or LARP or similar could organise a few photos to illustrate the wiki...

Why not have some of the more artistic among us draw "reconstructions" or "artists' impressions" of things? Maybe even, if possible, do a few rudimentary carvings or relief sculptures…

[the duke of nuke]

I think pictures of anything to do with Akana are a good thing, as long as they fit the setting and are of decent quality. Akana is about languages but, to my mind, not just about languages, which is why I write culture articles and enjoy others'

I'm no good at drawing personally, but Cedh and I have both contributed landscape photos (mine are here). More examples of costume, artefacts, in-world art, etc. whether drawn or photographed would all give the wiki a bit of depth and colour.

NeonFox: British LRP is also variable in costume standards, but for the bigger systems people tend to maintain it at a good level. Although costumes often do have anachronistic or ahistorical details I don't think that's so much of an issue for Akana, since we are in fact making it up!

[Neon Fox]

NeonFox: British LRP is also variable in costume standards, but for the bigger systems people tend to maintain it at a good level. Although costumes often do have anachronistic or ahistorical details I don't think that's so much of an issue for Akana, since we are in fact making it up!

Yeah, the fact that we're making it up is actually a problem, though. Because with SCA people, there's either Generic SCA Style, or whatever well-researched period someone is interested in--which will not be the same as any Akanan style. We'd basically have to get people to make e.g. Ndak Ta clothes, because Roman clothes are Roman, not Ndak Ta.

I'm not sure I'm expressing this well.

I think our best bet would be something like Zomp did for the various Almean clothes: a small set of generic silhouettes that could then get drawn over in stereotypical outfits for any given culture. There are all sorts of fashion templates out there, and it doesn't take huge amounts of artistic talent to draw clothes that look good.

(Of course, I both can sew and enjoy it, so I might actually be up for making an outfit or two, if consensus can be reached about what that means...)