Did Tsar bomba explosion seen in Finland ?

  • Context: Undergrad 
  • Thread starter Thread starter eldorado
  • Start date Start date
  • Tags Tags
    Explosion
Click For Summary

Discussion Overview

The discussion revolves around the visibility of the Tsar Bomba explosion from Finland, exploring the physics of light and distance in relation to the explosion's height and the curvature of the Earth. Participants examine the conditions under which the explosion could have been seen, considering both theoretical calculations and atmospheric phenomena.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant calculates that for the fireball to be seen from 1,000 km away, it would need to be at least 79.5 km high, given the Earth's curvature.
  • Another participant suggests that the visibility issue is akin to a distance-to-horizon problem, noting that an 8 km high fireball would not be directly visible from that distance.
  • It is proposed that observers in Finland might have seen a flash from the explosion illuminating high-level clouds or due to atmospheric effects, rather than the fireball itself.
  • A participant mentions the historical context of the Tsar Bomba, noting its size and the fact that it was reported as seen in Finland, but questions the implications of this information.
  • Another participant speculates that the fireball could have risen higher than 8 km, potentially allowing it to be seen from Finland.

Areas of Agreement / Disagreement

Participants express differing views on whether the explosion could have been seen directly from Finland, with some arguing against it based on calculations and others suggesting alternative explanations involving atmospheric effects. No consensus is reached regarding the visibility of the explosion.

Contextual Notes

Participants' calculations depend on assumptions about the height of the fireball and the curvature of the Earth. The discussion includes unresolved questions about atmospheric phenomena that could affect visibility.

eldorado
Messages
2
Reaction score
0
Hello :)

When I read about Tsar Bomba, I find that all sites say "The fireball touched the ground, reached nearly as high as the altitude of the release plane and was seen and felt almost 1,000 kilometres (620 mi) from ground zero."

Diameter of the fireball is 8 km.

Now , there are some premises :

1 Distance between the explosion & point that fireball seen is 1,000 km.
2 Circumference of the Earth is about 40000 km.
3 Angle between the two lines which passes through center of the Earth & ( ground zero & 1000 km point ) = (1000/40000)*360 = 9 degrees.
4 Sight line of 1000 km point is the tangent of the earth.
5 To see the explosion from 1000 km point , fire must be at least 79.5 km high.

this conclusion came from:

height of the fire to be seen 1000 km far = ( Radius of the Earth / Cos (9 degrees ) ) - Radius of the earth.so , how could the explosion seen from this distance when the height of the fire is only 8 km ?

thanks for help :)
 
Physics news on Phys.org
The question is essentialy a distance-to-horizon problem - but the other way around
Imagine an observer at the top of cloud looking to a point on the ground in finland

Distance to the horizon is roughly sqrt( 13*h ), with h in metres
So if h is 8km, 8000m, the horizon is = 320 km, so no you can't see the cloud directly.

You might have seen a flash due to the explosion illuminating high level clouds and reflecting the light, or some atmopsheric effect of exciting ions in some upper level.
 
Tsar Bomba was a 57 megaton hydrogen-bomb (which was decimated from its originally intended size of 100 megaton by removing material) and it is the largest device ever detonated on this Earth (at least in atmosphere). In 1961. Everybody got the message. Yes, it was reported as seen in Finland. And the blast wave was recorded three times (it circulated the earth). OK, so we know that you can blow it all up. So what? What now? Let's talk.
 
You might have seen a flash due to the explosion illuminating high level clouds and reflecting the light, or some atmopsheric effect of exciting ions in some upper level.

Thanks a lot for help :)

could you guide me to articles about this effect of illumination & the atmospheric ions ?

Thanks a lot :)
 
The diameter of the fireball might have been only 8 km, but I'm sure it didn't just chill there until it disappeared. I wouldn't be surprised if it rose to pretty close to the height that you calculated, where it could have been seen from Finland...
 

Similar threads

  • · Replies 10 ·
Replies
10
Views
4K
  • · Replies 16 ·
Replies
16
Views
7K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 31 ·
2
Replies
31
Views
5K
  • · Replies 10 ·
Replies
10
Views
4K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 10 ·
Replies
10
Views
6K
Replies
1
Views
5K