Tom asks:

> For a 13 year-old, this is an excellent first foray into doing professional 
> science. Although his basic hypothesis is plausible, his conclusions are 
> exceedingly unlikely to be true.
>  
> ---------------------------------
>  
> Plausible how?  From a couple of other numbers bandied about in the original 
> article, the asteroid is a couple hundred BILLION tons -- the satellite will 
> likely change the trajectory about as much as a fly hitting your windshield 
> will cause you to change lanes....

The mistake that you're making is that you're thinking like some modestly 
evolved, earth-bound, symmetrically bipedal anthropoid ape, whose every 
leaden motion must fight against the friction of dissimiliar surfaces, welded 
together and crushed by the force of gravity onto some meager planetary 
surface.

In contrast, if your car were in space, every fly impact would alter your course 
a bit. Because of the severity of this effect, NASA has studied a number of 
alternatives to pushing a gazillion tonne asteroid out of the way. Pay special 
to Table 4:

   http://www.nasa.gov/pdf/171331main_NEO_report_march07.pdf

One of the options is to simply park a relatively massive spacecraft (on the 
order of one or two hundred tonnes) next to an asteroid, but otherwise not 
touching it, and let it act like a "gravity tractor," slowly altering the orbit of 
the gazillion tonne asteroid.

Other options include painting a portion of the asteroid black and letting solar 
radiation pressure push the asteroid out of the way.

By comparison to these alternatives, the fly sounds like the way to go.

Wirt Atmar

* To join/leave the list, search archives, change list settings, *
* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *