[ExI] Asteroid Defence (Was: Re: META: Overposting (psychology of morals))

[Damien Sullivan]

On Fri, Mar 04, 2011 at 03:28:44PM -0800, Samantha Atkins wrote:

> >Don't need certainty; can simply push anything that remotely might hit
> >the Earth to an envelope where it certainly won't.  That raises the
> >costs in having to do more nudging, but lowers the costs in terms of not
> >needing as much force.
> 
> Really?  How far out do you need to start pushing and thus to detect
> it?  There are thousands of asteroids that cross earth orbit.  Would
> you just push all of them without calculation on grounds of "maybe"?
> Where are you getting that much delta v?

There's a middle you're excluding.  One can ignore Earth-crossing
asteroids that cross orbit months way.  I was talking about the ones that
pass within X thousand miles of Earth, where the astronomers say "1 in
100 chance it might hit us, we're not sure".  You don't have to wait for
absolute certainty of impact to divert, you can divert anything above a
certain expected value of damage.  What value?  Depends on how much you
can afford, obviously.

> >Stuff that's technically but not politically doable becomes doable if
> >you change enough minds.  Universal suffrage was a pipe dream until it
> >wasn't.  Giving up won't change anything, though.
> 
> And stuff that is not technically doable and/or not doable within a
> rational cost/benefit analysis should not be done no matter how many
> people you may be able to convince.   We cannot technically do

Well, yeah.  I was talking (a) generically against defeatism and (b)
about asteroid deflection.

-xx- Damien X-)