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I'm confused. A 100 ft asteroid that explodes 2.2 miles in the air seems to result in far more deaths from a 0.6 mile wide fireball compared to a 200ft asteroid

I'm confused. A 100 ft asteroid that explodes 2.2 miles in the air seems to result in far more deaths from a 0.6 mile wide fireball compared to a 200ft asteroid that would hit the ground in the same location (Fort Lauderdale, FL). 100ft = 211,172 deaths Is this correct? https://imgur.com/a/Elst6Q3 https://imgur.com/a/Elst6Q3

Metacelsus 4y ago
Air bursts give a wider area of destruction than ground bursts.
- deleted 4y ago
  [deleted]
- fitzroy 4y ago
  I knew this was true for nuclear weapons. It was just surprising that a smaller asteroid could be that much more dangerous than a larger one due to potentially exploding in the atmosphere.
  - jacquesm 4y ago
    Much the same mechanism sans radiation.
overcast 4y ago
For the same reason nuclear weapons detonate over the ground. Greater destruction. https://en.wikipedia.org/wiki/Air_burst https://en.wikipedia.org/wiki/Air_burst
sliken 4y ago
Digging a giant crater localizes the destruction and consumes most of the energy An air burst doesn't bother digging a giant crater and has a larger fraction of it's energy dumped into the atmosphere for fireballs, high winds, and direct radiation.
- midoridensha 4y ago
  I thought asteroids didn't normally produce any direct radiation; their explosions are purely from being superheated by the atmospheric friction. (Obviously, nuclear airbursts do produce a lot of radiation.)
  - sliken 4y ago
    Well potential energy is turned into kinetic energy, which heats up the asteroid. Any water, or gas inside could well result in an explosion. Things like turning night into day release a fair bit of radiation, like light. The Tunguska event is thought to be an airburst, that flattened many trees (80M or so), made an incredibly loud explosion, and it's claimed it was nearly as bright as the sun.
    - midoridensha 4y ago
      That's not radiation though. When people talk about "radiation", they don't mean light, they mean ionizing radiation, not everything across the entire EM spectrum.
  - dredmorbius 4y ago
    "Radiation" here refers to thermal radiation --- the direct radiant heat released through atmospheric friction and blast. The shockwave itself is also radiant energy, in this case a kinetic overpressure wave. Net impact effects are "wind blast, overpressure shock, thermal radiation, cratering, seismic shaking, ejecta deposition, and tsunami": <https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2017GL073191 https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/201...> Remember that "radiation" simply refers to any effect that radiates outward from an initial point or source, say, a radiator. Yes, common parlance has abbreviated "ionizing nuclear radiation" as "radiation", but that's only one of numerous types of radiant energy.
    - midoridensha 4y ago
      When someone says "a nuclear bomb releases heat and radiation", the radiation they're referring to is not thermal radiation. You're being pedantic.

Metacelsus 4y ago

Air bursts give a wider area of destruction than ground bursts.

deleted 4y ago
[deleted]
fitzroy 4y ago
I knew this was true for nuclear weapons. It was just surprising that a smaller asteroid could be that much more dangerous than a larger one due to potentially exploding in the atmosphere.
- jacquesm 4y ago
  Much the same mechanism sans radiation.

overcast 4y ago

For the same reason nuclear weapons detonate over the ground. Greater destruction. https://en.wikipedia.org/wiki/Air_burst https://en.wikipedia.org/wiki/Air_burst

sliken 4y ago

Digging a giant crater localizes the destruction and consumes most of the energy An air burst doesn't bother digging a giant crater and has a larger fraction of it's energy dumped into the atmosphere for fireballs, high winds, and direct radiation.

midoridensha 4y ago
I thought asteroids didn't normally produce any direct radiation; their explosions are purely from being superheated by the atmospheric friction. (Obviously, nuclear airbursts do produce a lot of radiation.)
- sliken 4y ago
  Well potential energy is turned into kinetic energy, which heats up the asteroid. Any water, or gas inside could well result in an explosion. Things like turning night into day release a fair bit of radiation, like light. The Tunguska event is thought to be an airburst, that flattened many trees (80M or so), made an incredibly loud explosion, and it's claimed it was nearly as bright as the sun.
  - midoridensha 4y ago
    That's not radiation though. When people talk about "radiation", they don't mean light, they mean ionizing radiation, not everything across the entire EM spectrum.
- dredmorbius 4y ago
  "Radiation" here refers to thermal radiation --- the direct radiant heat released through atmospheric friction and blast. The shockwave itself is also radiant energy, in this case a kinetic overpressure wave. Net impact effects are "wind blast, overpressure shock, thermal radiation, cratering, seismic shaking, ejecta deposition, and tsunami": <https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2017GL073191 https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/201...> Remember that "radiation" simply refers to any effect that radiates outward from an initial point or source, say, a radiator. Yes, common parlance has abbreviated "ionizing nuclear radiation" as "radiation", but that's only one of numerous types of radiant energy.
  - midoridensha 4y ago
    When someone says "a nuclear bomb releases heat and radiation", the radiation they're referring to is not thermal radiation. You're being pedantic.