Re: The Sparrow

On Sun, 11 May 2008 18:05:12 +0000 (UTC), jdnicoll@[EMAIL PROTECTED]
 (James
Nicoll) wrote:

>In article <W8uVd2AoGzJIFASG@[EMAIL PROTECTED]
>,
>GSV Three Minds in a Can  <GSV@[EMAIL PROTECTED]
> wrote:
>>Bitstring <g07a3j$88a$1@[EMAIL PROTECTED]
>, from the wonderful person 
>>James Nicoll <jdnicoll@[EMAIL PROTECTED]
> said
>>>In article <5Od+haAmihJIFA1e@[EMAIL PROTECTED]
>,
>>>GSV Three Minds in a Can  <GSV@[EMAIL PROTECTED]
> wrote:
>>>>
>>>>Ah, I forgot to mention the (missing) careful and detailed
consideration
>>>>of the orbital parameters, and day/night cycles which a planet
circling
>>>>a multiple star system would undergo. Although that may be due to the
>>>>rapid erasure of as much of the story from memory as I could manage.
>>>>
>>>       A habitable planet in the Alpha Centauri system would be
>>>orbiting one of the three stars, not both A and B or A, B and C.
>>>
>>>       From the perspective of A, B is about -21st magnitude. C
>>>is about 5th magnitude.
>>>
>>>       From the perspective of B, A is about -22nd magnitude. C
>>>is still about 5th magnitude.
>>>
>>>       From the perspective of C, AB would be about -6th magnitude.
>>>
>>>       For comparison, Sirius is about -1st magnitude to us, while a
>>>full moon is about -13. The sun is about -27. A different of
>>>five orders of magnitude translates into a difference in brightness
>>>of one hundred so for example from A, B would be roughly 1600x brighter
>>>than the full Moon but 1/250th the brightness of the sun, unless
>>>I messed up the math again.
>>
>>Although there are other more interesting orbital possibilities, iirc, 
>>like an occasional swap between primaries.
>>
>>(Can you put a habitable planet in orbit around C?)
>
>	It would be tide-locked but it currently appears that even
>a thin atmosphere can transfer enough heat to the nightside to 
>prevent all the volatiles from freezing out. 

The solar flares would have tendency to fry you.