[meteorite-list] Meteorites 101-Bolide

From: MEM <mstreman53_at_meteoritecentral.com>
Date: Sun, 16 Jan 2011 01:47:29 -0800 (PST)
Message-ID: <458828.98139.qm_at_web161901.mail.bf1.yahoo.com>

I largely agree, Chris, and like the overuse of the term "oriented", it seems
everything has become a "bolide"-- minor fireballs and major impactors alike.
The author on the work around the Chesapeake impactor adopted the term "bolide"
in his works and I believe that was a bastardized usage-- not based in
traditional usage. IMO a crater producing impactor is NOT a bolide unless it
produces an explosive terminus at altitude. An asteroid which excavates an 8
mile deep crater likely doesn't "bolide" upon encountering maximum aerodynamic
pressure, and no ground observer is likely to survive to tell us if there was
one anyway! Tagish Lake was by all accounts a super bolide having both the
magnitude and the report. I remember seeing the term bolide used in 19th century
descriptions, of course "areolite" was also a term used back then but I think
bolide --suitably defined has a use in literature, still.

I think the IAU should probably adopt a definition for bolide which narrows the
distinctions to reflect not just magnitude but disruption and audible report.
Traditionally "bolide" was used to describe a fireball that terminated in a
bright flash and /or explosive report. Having seen a traditional "bolide" up
close and personal, I can attest that it is not your regular fireball class
event. The "explosive" event is distinct from a sonic boom.

In preparation for this reply, I revisited the wiki page and I have a lot of
disagreement regarding the adequacy or magnitude alone being the distinction.
If we are to abandon the term bolide then we need a convention to describe a
fireball which terminates in an expanding/explosive disintegration with audible
report. IMO.

Elton




----- Original Message ----
> From: Chris Peterson <clp at alumni.caltech.edu>
> To: Meteorite-list at meteoritecentral.com
> Sent: Sat, January 15, 2011 7:53:49 PM
> Subject: Re: [meteorite-list] Meteorites 101
>
> Bolide is a term that it's good to avoid. It doesn't mean anything... or
>rather, it means too many different things. "Fireball" unambiguously means a
>meteor of a specific apparent brightness. "Bolide" is simply confusing.
>
> Chris
Received on Sun 16 Jan 2011 04:47:29 AM PST