[ExI] Asteroid on track for possible (probability of 1:25) Mars hit

[spike]

> bounces at lists.extropy.org] On Behalf Of Harvey Newstrom
> Subject: Re: [ExI] Asteroid on track for possible (probability of 1:25)
> Mars hit
> 
> On Tuesday 01 January 2008 15:41, spike wrote:

> > ...  {8-[  The object is large
> > enough that it could skim the treetops, but still wouldn't lose enough
> > velocity to go elliptical.  Its a direct hit or nothing.
> 
> Treetops?  On Mars?  Now that IS interesting!
> 
> --
> Harvey Newstrom <www.harveynewstrom.com>


Its a figure of speech Harvey.  If you hear rocket scientists refer to a
treetop orbit, that means the orbit with the lowest possible perigee (which
usually don't hold for very long because of drag from the upper atmosphere.)
There are reasons to get that perigee as low as possible for a lot of
scientific purposes, but it gives headaches to the satellite engineers.  We
are often heard to grumble that we fly as low as the customer wants, we will
need to clean the pine needles from our satellites.

spike