The bullet comparison is a good one to consider. I would think that both momentum and energy would be conserved with the torn apart asteroid. The event in Russia around the turn or the last century could have been caused by this type of behavior on a small scale. It would have been interesting to be beneath that one for a short time.
To obtain a good understanding of the damage caused by a broken up asteroid event, you must take into account the energy release. The momentum is not too important for a relatively small impact as compared to the large earth. I think the blast due to the energy release would be the most dangerous part of the episode. Think of the asteroid as one really big atomic weapon if intact or a million smaller ones if broken into a million parts. The mass of a sphere goes up as the cube of the radius so a body several miles in radius would cover a large area with a layer of material if spread out. I have a feeling that the atmosphere would be stripped away by anything of that nature. Dave -----Original Message----- From: Eric Walker <[email protected]> To: vortex-l <[email protected]> Sent: Sun, Feb 10, 2013 10:15 pm Subject: Re: [Vo]:Near earth asteroid info On Sun, Feb 10, 2013 at 7:10 PM, David Roberson <[email protected]> wrote: I realized I was preaching to the choir a bit with my broken up asteroid versus one big bad one. But, I actually do think that the total amount of energy deposited into the atmosphere and ground would be the same in either case. If it would destroy all the life on earth as a single hit, I would think it would do the same even if distributed over a large area. The energy is what does the damage. The light show would be most beautiful until the shock wave tore you into pieces. That would be a great way to leave the world! I suspect this is mistaken. Think of the difference between the momentum in a regular bullet, and the same momentum in the same amount of metal, pressed into a very thin foil with a large area. In the limiting case, I think the foil would be mostly harmless. In the example of the meteor versus the dust of the meteor once it has been blown to smithereens, it is the concentration of the momentum that seems most important. Eric
