3 ms·
The same photographer posted a very slow motion version of the same video: https://youtu.be/0tQ80Sj3QUs?t=122 https://youtu.be/0tQ80Sj3QUs?t=122 Also note that
by jewel 6y ago
The same photographer posted a very slow motion version of the same video: https://youtu.be/0tQ80Sj3QUs?t=122 https://youtu.be/0tQ80Sj3QUs?t=122
Also note that you can hit "." on a paused video on youtube to go frame-by-frame.
Some observations:
* The camera vibrates long before the pressure wave reaches it. I assume this is due to energy traveling through the ground (i.e. an earthquake).
* On the third building from the bottom left there is some light reflected from another building's windows. Once the camera stops moving, these seem to still be moving.
* As the camera falls, two frames show a Nikon camera strap and a separate camera. It appears as if the photographer is taking stills. I haven't been able to find that these photographs were published, perhaps none were taken of the blast.
- riquito 6y ago> * The camera vibrates long before the pressure wave reaches it. I assume this is due to energy traveling through the ground (i.e. an earthquake). Had to check it out, earthquake p-waves travel really fast! "Typical values for P-wave velocity in earthquakes are in the range 5 to 8 km/s." https://en.m.wikipedia.org/wiki/P-wave https://en.m.wikipedia.org/wiki/P-wave
- entropy_ 6y agoI live about 9km away from the site of the blast(as the crow flies). I can definitely confirm that the order of events was: 1 - Earthquake 2 - Sound (sounded like rolling thunder or a jet breaking the sound barrier) 3 - Pressure wave (felt as a sudden, short-lived, strong wind at that distance)
- brummm 6y agoI am curious about 2 and 3. Since sounds is also just a pressure wave, those two should have been the same speed as well. I guess the sounds must have travelled through the ground as well.
- anthony_r 6y agoThe speed of sound in pretty much any solid (or liquid) body is much faster than in the air. That's why the earthquake came first, and it was probably the earthquake that caused the 2. noises.
- spuz 6y agoThis is explained in the article. It describes the pressure wave as moving slower than the speed of sound. It was not a shockwave which would be generated by high-explosives which would travel at the speed of sound and be much more deadly.