CONCULTURE: dual planets

----- Original Message -----
From: "Michael Poxon" <m.poxon@...>

> If you're positing a planet with more than one moon and don't want tidal
> effects to be disastrous, the main criterion is mass,
> bearing in mind Newton's gravitation equation. All the examples we have of
> multiple, high-mass moon systems revolve around
> vastly more massive gas giants where your damgerously-high-tide effects
> don't matter. Mars has two moons but they're both tiny
> and would have a negligible effect on any Martian ur-water/life.
> You may also want to consider the fact that on a planet with a massive
> multi-moon system (because of the effects you describe)
> landbased life may simply not have been able to evolve in the first
> place -
> I don't know, I'm an astronomer rather than a biologist!
> Mike
Sorry to be tuning in so late to this!

Mike, if you're an astronomer, perhaps you could tell me if it's possible to
have two planets revolving around one another (roughly earth size), if this
is astronomically possible, how far apart they would have to be, how big
each planet would look in the sky to the other, whether there would be
orbital decay that would threaten both worlds, and whether there would be
disastrous tidal effects on both worlds.  I've been considering this kind of
system for a world I'm designing.  I had the vivid image of the remains of
dead cities stretching far out into the wet horizon, visible only a low
tide, that would be flooded with water when the tide came crashing in; land
masses that had cliffs, living cities moving further and further back as the
tide ate away at the coast line.  But I am decidedly NOT an astronomer, so I
don't know my physics, although I do read quite a lot about astronomy, but
as a rank amateur.  Would you be able to advise me?

yry wemry eftoihs!  Sally



> ----- Original Message -----
> From: "Sylvia Sotomayor" <kelen@...>
> To: <CONLANG@...>
> Sent: Monday, November 15, 2004 5:39 PM
> Subject: Re: CONCULTURE: First thoughts on Ayeri calendar system
>
>
>> On Monday 15 November 2004 08:53, Roger Mills wrote:
>> [lots of interesting stuff on moons & planets]
>> > Well, make that "18 to 70" for Carsten/me, respectively...:-) Neither
>> > of
>> > us, alas, seems to be near a university. It appears we could both
>> > profit
>> > from some good help and advice-- if either of you gentlemen are so
>> > inclined. Do you know of anything useful (intelligent-amateur level)
> that's
>> > on-line?
>> >
>> > Since this is basically Off-Topic, best if we discuss privately.
>> >
>> Not too off-topic! I've been following the discussion, since I'd like to
> have
>> 4 moons for Terjemar. But beyond some basic calculations, I haven't
>> progressed very far in determining size, distance, orbits, tides, etc.
>>
>> -S
>> --
>> Sylvia Sotomayor
>> sylvia1@ix.netcom.com
>> kelen@ix.netcom.com
>>
>> Kélen language info can be found at:
>> http://home.netcom.com/~sylvia1/Kelen/kelen.html
>>
>> This post may contain the following:
>> á (a-acute)  é (e-acute)  í (i-acute)
>> ó (o-acute)  ú (u-acute)  ñ (n-tilde)
>>
>> áe ñarra anmárienne cí áe reharra anmárienne lá;
>

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