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1970-01-01today at 2:08 AM1 replyview on HN

Your statement is not supported by, and is somewhat at odds with, physics. As described in this source, observed terminal brightening/"burst" of a bolide is tied to the body's material behavior (fragmentation, rapid lateral expansion, ablation), and not to a free-standing "deceleration shockwave" that exists independently of the body breaking up.

https://adsabs.harvard.edu/full/2001ESASP.495..491R


Replies

dredmorbiustoday at 3:18 AM

You're being excessively argumentative.

I didn't state that the shockwave is independent of whether or not the body breaks up, I wrote, emphasised, "Expanding the diameter of that particle field will increase the size of the resultant shockwave, whether the particle separation itself is "explosive" or not."

Which your article (partially read, sorry, incredibly shitty reader) largely substantiates, largely in the itemised list in section 2.2. Pancaking of a bolide through fragmentation increases frontal area, has multiple points of mass interacting with the atmosphere over a larger area and with less mass at each point, and the (undiscussed) light-emission mechanism which itself largely derives from compressive heating and ionisation of the atmosphere (rather than friction against the atmosphere or heating of bolide particles themselves). Increasing the number, and surface areas, of particles increases the region and intensity of this effect.

As your source discusses, most fragmentation is a result of mechanical rather than thermal forcing of the bolide.