I just heard the Napier pap(i)er providing an astronomical context for the YD event can be had on the public access site here: Cornell University Library.  I plugged in my name and am waiting for the verification code to be sent by email.

I’ll try to put the paper up on Scribed — if that is within the rules.  Then you can flip through it right here at The Tusk without signing in.  (I hope).  If not, you can apparently obtain it yourself through the site.

bill napier comets meteoritic explosions published journal articles