[meteorite-list] Meteorites 101-Bolide
From: Mark Bowling <minador_at_meteoritecentral.com>
Date: Sun, 16 Jan 2011 09:11:03 -0800 (PST) Message-ID: <331749.19262.qm_at_web161408.mail.bf1.yahoo.com> Hi?all, I have understood from my study that a bolide refers to a meteor that breaks up - not requiring the detection of an?audible report because, if observed from a distance, the sound may not be heard.??It is not?a bright meteor or fireball or large impactor, but simply a meteor that breaks up.? Right or wrong, that's the way I've been using the term when I report seeing one on the list.? Has anybody else been using it that way?? I've been lucky to have seen several dozen over the years (often colorful),?but?none up close like Elton (yet!). I would agree that the IAU should come up with a definition because the term?has come to mean too many things and?its use is?not going to go away any time soon.? In fact with the current explosion of public interest (no pun intended), more people are going to find the term and grab onto it. See you all soon! Mark B. Vail, AZ? ----- Original Message ---- From: MEM <mstreman53 at yahoo.com> To: Chris Peterson <clp at alumni.caltech.edu>; Meteorite-list at meteoritecentral.com Sent: Sun, January 16, 2011 2:47:29 AM Subject: Re: [meteorite-list] Meteorites 101-Bolide 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 ______________________________________________ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list at meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list Received on Sun 16 Jan 2011 12:11:03 PM PST |
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