How fast will that measly 800 pound kinetic impactor be travelling when it hits the comet? The article doesn't say, but does state, "According to a senior official associated with the project, the impact, they hope, will put an end to all the speculation about the interiors of comets." That reference to the interior of the comet leads me to believe that it's planned to be a big enough collision to break apart at least parts of the comet. I would be very surprised to learn that they have calculated the trajectories of the pieces that break off.
Cordially,
> How fast will that measly 800 pound kinetic impactor be travelling when it hits the comet?
Relative to what?
> I would be very surprised to learn that they have calculated the trajectories of the pieces that break off.
I wouldn't. The 800 pound hammer with transfer it's kinetic energy to the comet; much of that energy will be converted to heat. As for the rest, it might blow a few fridge-sized chunks off at a few hundred feet per second.
I'm not sure what the 22,000 MPH reference is to, but it could be referring to the closing speed just before the impact. The last sentence of the article says,
The collision between the projectile and the comet, at a speed of 22,000 mph, will take place 83 million miles away from Earth.Man, 800 LBS at 32,000 feet per second .. that is one whopper of a projectile!
"I would be very surprised to learn that they have calculated the trajectories of the pieces that break off."
In all honesty, and maybe I'm naive, but i'd be amazed if they didn't try to calculate the effect of their "celestial hammer". Did you mean that such a calculation is beyond mans ability?
Article says it'll hit at 22,000 mph. If you consider that a very small paint chip once put a noticeable ding in a Space Shuttle window, I'd say this little guy is gonna blow the comet to smithereens.