4 ms·

So Fat Man and Little Boy were approx 15-20 kT. Is that apples to apples? If so, holy crap.

DanBC 14y ago
Ground Zero allows you to pick a place and a bomb and nuke an area. Unfortunately it hops from 21 kT to 400 kT, but still. (http://www.carloslabs.com/projects/200712B/GroundZero.html http://www.carloslabs.com/projects/200712B/GroundZero.html)
- drakeandrews 14y ago
  Nuke Map allows you to enter the yield of your choice. http://nuclearsecrecy.com/nukemap/ http://nuclearsecrecy.com/nukemap/
- uvdiv 14y ago
  This is actually completely useless since these explosions are far closer to the earth -- probably between 100 meters and 1 km altitude [1], vs. 10-30 km estimates for this meteor. Also, it only shows thermal radiation effects, which are insignificant here. This is an appropriate calculator for meteors [2-3], including the effects of the actual blast (overpressure), not just heat. The documentation says windows are shattered at about 6,900 Pa (1 psi). [1] https://en.wikipedia.org/wiki/Effects_of_nuclear_explosions https://en.wikipedia.org/wiki/Effects_of_nuclear_explosions [2] http://impact.ese.ic.ac.uk/ImpactEffects/ http://impact.ese.ic.ac.uk/ImpactEffects/ [3] http://www.purdue.edu/impactearth http://www.purdue.edu/impactearth (Flash)
  - cynwoody 14y ago
    Here's what it's like to be 10,000 feet below a 2kt nuke (1957). https://www.youtube.com/watch?v=BlE1BdOAfVc https://www.youtube.com/watch?v=BlE1BdOAfVc
johngalt 14y ago
Measuring the total energy release of a meteor vs a nuclear weapon yield is not an apples to apples comparison. Not when measuring destructive force.
- damoncali 14y ago
  Care to explain further? Is it a time thing, placement? What?
  - asselinpaul 14y ago
    I believe it is because most of the damage done by a nuclear bomb is caused by radiation, not by the initial blast (do correct me if I'm wrong, I am by no means an expert).
    - mikeash 14y ago
      Not really. The fallout can be a significant danger, depending on the bomb size and design. However, it's much easier to survive than the initial blast, in general. It can be a substantial problem for survivors, but the blast will kill far more. The main reason the explosions aren't comparable is because this meteor exploded far higher than a nuclear bomb would detonate. By the time the blast reached the ground, the energy had been spread out over a large area. If it had exploded at a typical nuclear bomb detonation height (say, 1km or so), the destruction would have been comparable, although survivors wouldn't have to worry about finding shelter from fallout.
  - jlgreco 14y ago
    Since we are talking total energy release, it becomes hard to compare them since a meteorite dumps a significant amount of it's energy into the atmosphere in a much slower and widespread fashion, whereas a nuclear device does it in one place at one time. Now I'm pretty sure that if you get a big enough meteorite moving fast enough, the distinction becomes much fuzzier and the real important factor becomes just how much thermal energy was added to the atmosphere.
ChuckMcM 14y ago
Yes, its the same scale, but explosions in atmosphere distribute their energy over the surface of a sphere. Surface goes up with the square of the radius (hence the inverse square law in so many things). Here being far enough away helps, the over-pressure broke non-tempered glass of the buildings closest but not the tempered glass of the vehicles. I've watched three shuttle re-entries (benefit of being in California when they were landing in Florida) when the shuttle entered a dense enough atmosphere to create a contrail it looked very similar to this one (although it had a glowing purple leading edge which I never did get a satisfactory explanation for). I've tried to imagine what this sort of event would look like to someone driving, now I know. Personally I would be expecting the shock wave so I would try to find some place to pull off an avoid being directly impacted by it. I did some experiments with hydrogen and oxygen in a misspent youth (its a pretty powerful explosive at the correct mixture) and the shock wave can take your breath away.
- param 14y ago
  sounds like a well spent youth to me!
Florin_Andrei 14y ago
Rocks from space release their energy a bit more gradually, and higher. Nukes go pop all at once, closer to ground (but depends on the nuke, I guess).
dredmorbius 14y ago
Yes, however both of those bombs were specifically targeted, and were detonated at 2000' (Hiroshima) and 1500' (Nagasaki) above ground level, vs. 20-30 miles (105,000' - 158,000') above ground for the Chelyabinsk meteor. Blast effects trail off markedly with distance. For Hiroshima, most blast damage was confined to a radius of 1.6 km from ground zero, roughly correlating to an overpressure of 5 psi. Glass will fragment at much lower pressures, generally 0.14 - 1.4 psi. Blast damage falls as the inverse cube of distance. The difference between mother nature and a human adversary is that Mom has zero fucks to give for where she does her work. Asteroid impacts are randomly distributed around the planet, for the most part (latitude may play some role). Most impacts should occur over oceans. Russia, being the largest country, and Siberia, being the largest region of Russia, will tend to see more impacts than other areas, though on an area-normalized basis the maths should work out. So while we may see larger energy releases from space impacts, they'll typically be targeted away from populated regions. Not that a large enough impact couldn't still make for a really bad day.

DanBC 14y ago

Ground Zero allows you to pick a place and a bomb and nuke an area. Unfortunately it hops from 21 kT to 400 kT, but still. (http://www.carloslabs.com/projects/200712B/GroundZero.html http://www.carloslabs.com/projects/200712B/GroundZero.html)

drakeandrews 14y ago
Nuke Map allows you to enter the yield of your choice. http://nuclearsecrecy.com/nukemap/ http://nuclearsecrecy.com/nukemap/
uvdiv 14y ago
This is actually completely useless since these explosions are far closer to the earth -- probably between 100 meters and 1 km altitude [1], vs. 10-30 km estimates for this meteor. Also, it only shows thermal radiation effects, which are insignificant here. This is an appropriate calculator for meteors [2-3], including the effects of the actual blast (overpressure), not just heat. The documentation says windows are shattered at about 6,900 Pa (1 psi). [1] https://en.wikipedia.org/wiki/Effects_of_nuclear_explosions https://en.wikipedia.org/wiki/Effects_of_nuclear_explosions [2] http://impact.ese.ic.ac.uk/ImpactEffects/ http://impact.ese.ic.ac.uk/ImpactEffects/ [3] http://www.purdue.edu/impactearth http://www.purdue.edu/impactearth (Flash)
- cynwoody 14y ago
  Here's what it's like to be 10,000 feet below a 2kt nuke (1957). https://www.youtube.com/watch?v=BlE1BdOAfVc https://www.youtube.com/watch?v=BlE1BdOAfVc

johngalt 14y ago

Measuring the total energy release of a meteor vs a nuclear weapon yield is not an apples to apples comparison. Not when measuring destructive force.

damoncali 14y ago
Care to explain further? Is it a time thing, placement? What?
- asselinpaul 14y ago
  I believe it is because most of the damage done by a nuclear bomb is caused by radiation, not by the initial blast (do correct me if I'm wrong, I am by no means an expert).
  - mikeash 14y ago
    Not really. The fallout can be a significant danger, depending on the bomb size and design. However, it's much easier to survive than the initial blast, in general. It can be a substantial problem for survivors, but the blast will kill far more. The main reason the explosions aren't comparable is because this meteor exploded far higher than a nuclear bomb would detonate. By the time the blast reached the ground, the energy had been spread out over a large area. If it had exploded at a typical nuclear bomb detonation height (say, 1km or so), the destruction would have been comparable, although survivors wouldn't have to worry about finding shelter from fallout.
- jlgreco 14y ago
  Since we are talking total energy release, it becomes hard to compare them since a meteorite dumps a significant amount of it's energy into the atmosphere in a much slower and widespread fashion, whereas a nuclear device does it in one place at one time. Now I'm pretty sure that if you get a big enough meteorite moving fast enough, the distinction becomes much fuzzier and the real important factor becomes just how much thermal energy was added to the atmosphere.

ChuckMcM 14y ago

Yes, its the same scale, but explosions in atmosphere distribute their energy over the surface of a sphere. Surface goes up with the square of the radius (hence the inverse square law in so many things). Here being far enough away helps, the over-pressure broke non-tempered glass of the buildings closest but not the tempered glass of the vehicles. I've watched three shuttle re-entries (benefit of being in California when they were landing in Florida) when the shuttle entered a dense enough atmosphere to create a contrail it looked very similar to this one (although it had a glowing purple leading edge which I never did get a satisfactory explanation for). I've tried to imagine what this sort of event would look like to someone driving, now I know. Personally I would be expecting the shock wave so I would try to find some place to pull off an avoid being directly impacted by it. I did some experiments with hydrogen and oxygen in a misspent youth (its a pretty powerful explosive at the correct mixture) and the shock wave can take your breath away.

param 14y ago
sounds like a well spent youth to me!

Florin_Andrei 14y ago

Rocks from space release their energy a bit more gradually, and higher. Nukes go pop all at once, closer to ground (but depends on the nuke, I guess).

dredmorbius 14y ago

Yes, however both of those bombs were specifically targeted, and were detonated at 2000' (Hiroshima) and 1500' (Nagasaki) above ground level, vs. 20-30 miles (105,000' - 158,000') above ground for the Chelyabinsk meteor. Blast effects trail off markedly with distance. For Hiroshima, most blast damage was confined to a radius of 1.6 km from ground zero, roughly correlating to an overpressure of 5 psi. Glass will fragment at much lower pressures, generally 0.14 - 1.4 psi. Blast damage falls as the inverse cube of distance. The difference between mother nature and a human adversary is that Mom has zero fucks to give for where she does her work. Asteroid impacts are randomly distributed around the planet, for the most part (latitude may play some role). Most impacts should occur over oceans. Russia, being the largest country, and Siberia, being the largest region of Russia, will tend to see more impacts than other areas, though on an area-normalized basis the maths should work out. So while we may see larger energy releases from space impacts, they'll typically be targeted away from populated regions. Not that a large enough impact couldn't still make for a really bad day.