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I just noticed that I sent a reply to Jose, but didn't include adding the meteorite-list. So...resending my response again, but to the list only this time.
GeoZay
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Hello Jose,
I believe it's more reliable than most people realize and you are right partially...But there are a number of guidelines that one can refer to in regards to the parentage of meteors that I wouldn't disregard. The following are some guidelines that I've formulated from my experience in recording meteor data that you might find useful?
a) if a meteor appears very fast, it is reasonably certain that it is of cometary origin and not asteroidal. If one should happen to be traveling that fast for some unknown reason, it most likely won't be producing any meteorites. A good bet that it will terminal burst and nothing to be found, but dust.
b) if a meteor appeared very slow and non fireball status, I'd be inclined to think of it as also being cometary...particularly if no sonic booms were reported. This is based on asteroidal material being made up of denser material than the typical cometary meteoroid whose texture is pretty much like fluff. Even a small piece of asteroidal material (such as rock or iron) will appear quite brite. Only with the micrometeorites(visible and non-visible) will there be any doubt, but I think for the typical meteorite hunter they aren't too concern about micrometeorites?
c) if a meteor appeared very slow and had fireball status accompanied by reports of sonic booms, It's no doubt of asteroidal(or moon/mars) origin.
d) if a Meteor was a fireball, Very slow and not associated with a cometary shower thru radiant alignment, I'd be inclined to consider it likely being asteroidal....provided the event occurred between noon and midnight. The closer the event occurred to 6 pm local with the above circumstances, the more I'd be inclined to think of it as an asteroidal object.
e) If a meteor appeared very slow and lasted a minute or two, most likely re-entering satellite.
f) A fireball lasting only a few seconds is highly unlikely to be a satellite re-entry.
g) if a fireball occurred with any velocity(Very Slow thru Very Fast) after midnight and before 9 am local, I'd be incline to think of it being cometary.
I think that's all the guidelines I'd use in classifying whether a meteor was generally cometary or asteroidal and thus a possible meteorite dropper. I've never written them down before, but these are what I look for instinctively. As for the Taurids you mentioned above, I've only watched for the North and South Taurids. I'm not familiar with "E Taurids". Maybe a typo perhaps? The N. and S. Taurids active period is considered to be from Oct 1 thru Nov 25 with a peak for the N. Taurids on Nov 12. The S. Taurids peak occurs on Nov 5. If you are referring to either or both of these Taurids, their entry velocity is between 27 and 29 km/s. Visually I'd consider these velocities as being Slow to Medium....Very distinct looking compared to the typical asteroidal object entering usually with velocities less than 23 km/s. I'm pretty certain if I seen something with a velocity like that of a N. Taurid, I'd be highly inclined to think of it being cometary. However, out of the 40 meteor showers recognized as being active enough to warrant watching, only 6 have entry velocities that might cause confusion due to their velocites. And these can usually be eliminated or considered if they should happen to be active or not at the time a suspect fireball was observed. It may seem like a lot of if's and but's, but once these guidelines are firmly implanted, a suspect fireball can be quickly and reasonably judged as to whether it's worth chasing down meteorite potentials or not.
George Zay
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- [meteorite-list] re: meteor velocity Marco Langbroek
- GeoZay
