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Can we see nuclear explosion from orbit?

  1. Mar 25, 2010 #1
    As topic says

    Can we see Nuclear Explosion form orbit altitued? or even form space?

    Just curious.
  2. jcsd
  3. Mar 26, 2010 #2


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    You can see manmade buildings from space. A nuclear explosion is certainly bigger and brighter than any manmade building. We can also see nuclear explosions in space quite easily; see:

  4. Mar 26, 2010 #3
    Errr, which buildings exactly? As well you more than likely would not be able to see the actually explosion (as in the visible energy coming out) from space. Our average nuclear bombs aren't really 'that' powerful. You might be able to see just the first few moments of the explosion if you knew where to look and were given good conditions but it wouldn't last too long and would probably just look like a 'bright' point. Space is quite a distance. The average nuclear bomb however would have no problem pushing a mushroom cloud through and over most clouds. The problem is knowing what and where/when to look for it.

    Unless the OP means by the aided eye, in which case everything is visible
    Last edited: Mar 26, 2010
  5. Mar 26, 2010 #4


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    Assuming by "space" the OP just means low earth orbit, a nuclear explosion is orders of magnitude larger than what is necessary to see with the unaided eye. From LEO, you can see a large campfire! Or consider it from the other direction: you can see most satellites with the naked eye from the ground. They are much, much dimmer than a nuclear explosion as they are merely reflecting light from the sun. Then, certain satellites with flat, reflective surfaces will "flare", reflecting direct sunlight to a small area on earth. These are spectaclarly bright to the naked eye - much brighter than any star or planet. http://www.satobs.org/iridium.html
  6. Mar 26, 2010 #5


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    Some links I've seen put the human eye's resolution at 0.6 arcmin: http://clarkvision.com/imagedetail/eye-resolution.html

    The ISS is at an altitude of 173 miles, so at that resolution, the unaided human eye can resolve an object 159 feet wide. There are individual buildings larger than that.

    You can probably see an airburst nuke on Earth from the Moon.
  7. Mar 27, 2010 #6
    Bright as the sun.
  8. Mar 27, 2010 #7
    I sincerely hope we never see one from space.
  9. Mar 27, 2010 #8

    I had an Iridium flare happen to me just last week. I was using my finder scope to get set up on M42 and this big flash happened. Scared the poo out of me!
  10. Mar 28, 2010 #9


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    I've seen a couple unexpectedly, but assumed I knew what they were and was just upset I didn't have a camera ready. You can jump onto www.heavensabove.com to confirm what you just saw.
  11. Mar 28, 2010 #10
    Funnily enough, I was just thinking the very same thing yesterday, as I was reading about the largest bomb ever made by humans, a 57 megaton hydrogen bomb that the Russians detonated over Novaja Zelmlja in 1961. (LINK)
  12. Mar 28, 2010 #11
    The average nuclear weapon is far from this size, lol. I think in America they are on average 100-300kT. In Russia they go up to 500kT.
  13. Mar 29, 2010 #12
  14. Mar 29, 2010 #13
    I guess I should have said the average active weapon to make it clearer what I was saying. Yes there was a time period where people thought that making powerful weapons was the best and so big weapons exist. Most are not active though, majority are retired and recycled for other weapons.

    Something we have to think about with this is that a lot of released visual wavelength energy gets absorbed before leaving the atmosphere. A HANE would definitely be visible but a ground explosion, I'm not sure... it'd probably just be a really quick flash which would be obscured quickly
  15. May 16, 2012 #14
  16. May 16, 2012 #15
    It all depends what you are looking with.... If you are using your eyes, distance is finite... If you are using an gamma ray/xray telescope pointed in the right spot.... you could see one from light years away.
  17. May 17, 2012 #16


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    You can easily see lightning from orbit, which it is much less brightness and duration than a nuclear explosion.
  18. May 17, 2012 #17


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    Not that much. A nuke is VERY bright, MUCH brighter than you think it is. The flash, fireball, and resulting cloud would very easily be seen from orbit.
  19. May 17, 2012 #18
    I vaguely remember reading somewhere that the only thing you can see from space is the Great Wall of China. However, I don't think this is right because China is on the other side of the earth. Maybe they mean at night. Anyway, here is a web site that might help.
    A nuclear explosion as seen from space.
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