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CONCULTURE: First thoughts on Ayeri calendar system

From:Simon Richard Clarkstone <s.r.clarkstone@...>
Date:Monday, November 15, 2004, 1:46
Carsten Becker wrote:
> So for the time being, I thought it would be quite > interesting to have two moons -- though I haven't done my > homework about how long the moons' cycles must be and how > far they are away from the planet etc. etc.
3-body systems are chaotic and hence (in the general case) not stable. Generally, the smallest of the three bodies ends up either hitting something or getting flung away. One _can_ have a reasonably stable system if either: * There is one huge body with much smaller bodies orbiting it. (e.g. the solar system) Both moons would be too small to be easily seen. * two bodies orbit each other closely with one much further away. (e.g. the sun-moon-earth system) Either one moon would be too small/far away to be easily seen, or the moons would form a pair, and hence stay close to one another in the sky (interesting but not what you are describing).
> Without any > scientific justification, I assumed Moon A to have 24-day > cycles and Moon B to have 60-day cylcles. Furthermore, I > assumed that the moons both have irregular orbits, like > when drawing something with the Spirograph if you know that > thingy.
The act of causing tides tends to make orbits a) more circular b) larger (energy is lost, so the moon recedes, as ours is)
> So Moon A needs ~1/4 year (455.75/4 = 113.9375 > days) to be at the same position where it started and Moon > B needs ~1/2 year (455.75/2 = 227.875 days) for that. These > second cycles s/would be best called "big cycles" I guess, > the month cycles "small cylces". > > Distinctive points then would then be (S = sun; P = planet; > A = moon A; B = moon B; yrs = years; ds = days): >
[large diagrams snipped] I can see a problem brewing here, though there is nothing _per se_ wrong with the above. In general, make sure you know whether you are measuring positions/angles relative to the fixed stars, or relative to some existing line (e.g. planet-sun). Find an astronomer to help with all the difficult bits, being at university helps. (but I don't even know if you're 8 or 80)
> That would mean there'd be a lunar and/or solar eclipse > every quarter year?
No. That would only happen if the orbits of everything were exactly on a plane. In practice, the planes of all the orbits are slightly different, so thing come (apparently) close to each other, but do not eclipse. -- Simon Richard Clarkstone*rkst*n* / s*m*n_cl*rkst*n*