6 ms·

Had that impact hit the ground it would have released over 100 kilotons of energy. It would have been far, far more destructive and deadly.

jlgreco 14y ago
But without an atmosphere the shockwave from that 100 kiloton explosion should be pretty minimal (through the ground only), and any debris flung into the atmosphere would fall right back down on parabolic trajectories (or go into orbit), not linger in the sky for months/years. The danger posed by such an explosion, off the top of my head, would be getting hit by the object itself, getting hit by falling debris ejected by the explosion, structural damage from the shockwave that traveled through the ground... I'm not sure what else. Of course without an atmosphere everyone would be dead anyway, so I suppose this is kind of a silly thing to think about.
- danbruc 14y ago
  Of course without an atmosphere everyone would be dead anyway, so I suppose this is kind of a silly thing to think about. Just never walk out of your front-door without wearing your space suit.
  - jlgreco 14y ago
    Hmm. Living in pressure vessels makes structural damage to buildings a great deal more dangerous.
- InclinedPlane 14y ago
  Sort of, there's still a blast wave from the vaporized rock, and there's still the ejecta blanket (which could easily ruin your day if any of it hit you).
Ma8ee 14y ago
How could it release more energy if it hits the ground? The total kinetic energy released must be the same whether it is released in the atmosphere or on impact with the ground.
- marcosdumay 14y ago
  The toal energy released is the same. The total energy released on the impact is quite different.
- InclinedPlane 14y ago
  100 kilotons of energy released along a several hundred kilometer long tube in the upper atmosphere, at altitudes of tens of kilometers poses much less of a threat to people who live on the surface of the Earth than if all that energy is released at once on the ground.

jlgreco 14y ago

But without an atmosphere the shockwave from that 100 kiloton explosion should be pretty minimal (through the ground only), and any debris flung into the atmosphere would fall right back down on parabolic trajectories (or go into orbit), not linger in the sky for months/years. The danger posed by such an explosion, off the top of my head, would be getting hit by the object itself, getting hit by falling debris ejected by the explosion, structural damage from the shockwave that traveled through the ground... I'm not sure what else. Of course without an atmosphere everyone would be dead anyway, so I suppose this is kind of a silly thing to think about.

danbruc 14y ago
Of course without an atmosphere everyone would be dead anyway, so I suppose this is kind of a silly thing to think about. Just never walk out of your front-door without wearing your space suit.
- jlgreco 14y ago
  Hmm. Living in pressure vessels makes structural damage to buildings a great deal more dangerous.
InclinedPlane 14y ago
Sort of, there's still a blast wave from the vaporized rock, and there's still the ejecta blanket (which could easily ruin your day if any of it hit you).

Ma8ee 14y ago

How could it release more energy if it hits the ground? The total kinetic energy released must be the same whether it is released in the atmosphere or on impact with the ground.

marcosdumay 14y ago
The toal energy released is the same. The total energy released on the impact is quite different.
InclinedPlane 14y ago
100 kilotons of energy released along a several hundred kilometer long tube in the upper atmosphere, at altitudes of tens of kilometers poses much less of a threat to people who live on the surface of the Earth than if all that energy is released at once on the ground.