The revelation that Schwassmann-Wachmann (hereafter SW3) left a cosmic calling card during it’s last pass is significant. The comet returns every 5.4 years. The next pass should be around November 2011. Some time around then we could expect another cometary shower. The intensity of the encounter would seem to be a function of the degree of fragmentation of SW3, which has been underway since at least 1995, and appears entirely unpredictable.
If this same stuff — ball lightning and other weird effects — happened in the deep or relatively recent past, no crater would remain, and the events would be detectable only in myth or stories from isolated locales around the world (and perhaps with more sophisticated and open-minded field investigation). There was no video back in the day.
That’s about the extent of my knowledge, but it sends a little chill up my spine. Anyone know of a reason my spine should not so shiver when contemplating the return of SW3’s cometary fireballs? Don Yeomans??
PS. Any insight to the exact timing of these events (or non-events the case often is with comets) would be appreciated. Orbital dynamics are not my thing.