Re: starship-design: Massively Distributed Computing for SETI

[KellySt@aol.com]

In a message dated 3/18/01 12:46:14 PM, bfranchuk@jetnet.ab.ca writes:

>> Zenon's best case was a 100 km antenna, which is probably the one we
>should
>> go with given the power densities we need. Since even relatively small
>> airborne phased array antennas of approximately one meter square contain
>> between 2000 and 3000 emitters, we can use the smaller number to estimate
>> the number of emitters and therefore the computing power necessary.
>
>First of with the power levels involved I don't expect to have a lot of
>very small emitters. Secondly since the array is so large, I expect the
>math can be simplified down, and since a block of emitters will have its
>own cpu for control a lot of calculations can be done locally. It may even
>be possible to have a incremental algorithm that updates partial factors
>with a recalculation every hour or so.
>Remember the scale -- HUGE distances to travel, thus a long time frame
>for travel. This is something that will take several generations to finish
>thus realistic goals must be set for each generation.
>I also expect that the fastest possible craft at this time (anti-matter
>drive)
>craft @ .4C for a one way trip would be .1C for a practical usable
>craft ie:Payload, and .05C for a beamed energy craft.


I was getting significantly better speed numbers.  More importantly a mulit 
generation ship is a collosal waste.  It requires a vastly larger, heavier, 
more complicated ship.  So much so, that the same propulsion gear could get 
you there in a fraction of the time.  Hence a small craft that would get 
there in years, would be easier to do then one that would get there in 
decades.

Also trips that take generations are assured to get their AFTER ships sent 
out decades after it left.  Assuming anyone would bother to send them.