(meteorobs) neos versus mbas

Thu Oct 20 08:57:46 EDT 2011

John
I do not believe anyone has put forth that any NEO are producing 
meteor showers.If I missed such statements please point them out to me.In 
addition with all the visual and camera recorded events observed over the many 
years these are only a small fraction of fireballs that actually hit the earth 
each year.Let take these visual and camera recorded events that have 
produced orbitial inforamation you are looking at an even smaller pool of data 
to work from.Let leave out visual observations and look at the camera data there 
are less than handful world wide that are producing orbital data. Let throw in 
basicly that data from nearly one hemishpere is lacking on a daily,weekly, 
yearly time frame So it seems to me a stretch to say that there is no way that 
NEO produce zero fireballs.
One part of your post seem to suggest that main belt asteroid are different than 
NEO.Based on what? Spaceweathering? Then you state mainbelt meteorites have been 
found on earth.You seemed to be putting out conflicking blanket statements that 
you yourself have very little data to support your position and is based more in 
theory.
Hey,seems we are where we were over a decade ago where the general theory,which 
was held for decades, that on average visual observer only would see one or two 
fireballs a year from any location.Then that as been proven wrong  but I am sure 
some experts still hold to that theory even today.
My point is that to make any statement at this time that it is impossible for 
NEO to produce any fireballs is non-sense.John,my view is in the next 25 years 
we will see that least a small population of fireball over the earth having a 
link to NEOs.
http://www.projectasteroid.org/composition.htm
This link seems to suggest that some meteorites represent the NEO population. I 
wonder how they got to earth?
The other point is that we should be on the look out for fireball meteorite 
dropping events that  may represent the NEO meteorite population that have been 
found so far on Earth.What is the harm if it advances our understanding of the 
NEO phenomena?Remember in any era the leading scientific authority has been some 
of the biggest stumbling block to the advancement of science because of closed 
mindedness.
Regards
Thomas  

________________________________
From: "metpaper at Safe-mail.net" <metpaper at Safe-mail.net>
To: meteorobs at meteorobs.org
Sent: Mon, October 17, 2011 3:21:49 PM
Subject: (meteorobs) neos versus mbas

Thomas Dorman commented :-

"But  the data on Asteroids is pretty clear.
http://www.johnstonsarchive.net/astro/asteroidmoons.html
That other asteroid bodies can orbit and be present with other asteroid 
bodies.So it does seems,to me and not a great leap of logic or 
genuis, that such  fireball events could be possible. In addition if what is now 

believe that some asteroids are died comets this would seem to increase the 
possibilities of such event taking place.May I point  just one event that 
support what I am talking about asteroid 596 Scheila event this year.
Just pointing this out. Call me crazy,I have thick skin and can live with it."

You are confounding Near Earth Objects and Main Belt Asteroids.  Deep time and 
timescales are very important in astronomy, but although astronomers are capable 
of coping with deep space and immensities, and through cosmology the oldest of 
ages, they don't really have any feeling for deep time.

The "characteristic timescale" of mechanisms lends a strong key to many things 
astronomic in the physics context.

McSween Jr's Meteorites and Their Parent Planets is my fave rave on meteorite 
sources.  Jennisken's recent book (magnum opus) with respect to meteors and also 
their parent sources I've not seen a copy of, being just a bit beyond my pocket, 
but it's available.

Basically (596) Scheila has no bearing on the matter at all, happened a few news 
headlines ago, in the Main Belt, whilst the NEOs being commented upon here may 
have been ejected out of the Main Belt so long ago that it was before Africa 
stopped being an island.  Or North and South America joined up last time.  And 
has lived in sparsely populated orbital domains since then, unlike (596).

If you want to play the asteroid to meteorite - fireball game, then you look at 
NEOs that are likely bits knocked off of (4) Vesta, these have been identified 
minearologically from groundfalls and photometrically and spectrophotometrically 
from NEOs and (4) Vesta.

I have never heard of anyone claiming bunching or showers connected to any of 
them.  Maybe I haven't looked hard enough.

In more shallow time we've had people observing and recording for around two and 
a half millennia, in a regulare and organised way by people employed by state 
bureaucracies , even if their remit was to look for "portents".  With meteors it 
isn't always good news as they were long considered atmopsheric phenomena, so 
not necessarily logged like hairy stars or guest stars were.  Although I believe 
some meteor storms have been.

In shallowest time we've had people observing naked eye in an organised way for 
a century and a bit, since at least Denning.

And these near earth objects have been orbiting for a long, long time, and are 
often in quite stable orbits despite pertubation effects.

Many showers are known and confirmed now where you will see rates quoted for 
their faint meteors of 1 per hour.

The concept that fireball event clustering at specific times and dates (which 
would occur if NEO connected, not entirely dissimilar to the context of the 
recent Giacobinid... [sorry, showing my age, I mean Draconid shower], because of 
orbital periodicity) and not be known by now even prior to modern methodologies 
is a bit galling to some, annoying to others.

The core of long running pseudoscience is that it sounds reasonable and 
acceptable and scientific but it's always in a vein of "well, it could be".  
Science says "make me a prediction, based on your assumptions, said assumptions 
being guided by the conclusions you've reached from your perusal of the 
available data, and make that prediction not only testable, but preferably 
uniquely testable, so that coincidence, happenstance and alternate 
hypotheses/models can be dismissed whilst yours are supported".

(596) Scheila is not a Near Earth Object.  It does not exist in the same 
environment as Near Earth Objects.  It does not share the same recent orbital 
evolution and orbital dynamics as a Near Earth Object.  Yet all these matters 
are relevant to its collision.  Extrapolating from such an object in such an 
environment to another object not in such an environment, when the environment 
is highly relevant to the phenomenon under consideration, is a leap, and not a 
logical extension nor a reasonable assumption.

A more interesting avenue of investigation would be to consider the NEO that 
have been radar imaged as binary during a close apparition to Earth.  And asking 
whether any cloud of debris surrounding these objects would've been detected as 
a scintillation or some other affect upon the radar signal.  A "fog", for after 
all they would be of the same material as the surface regolith.  Now, I don't 
know enough about those sorts of things, so I have to look it up, or just hope 
one day someone will tell me.  I do not have to insist that such a debris cannot 
exist because the radar has not seen it, because I don't know the physics.  
Neither do I insist that such a debris is possible and that it remains possible 
until someone has most definitely proven it not to be the case.  Because at 
present I cannot test this hypothesis even sufficiently enough to say as to 
whether or not it is pure bunkum.  Both because of lack of knowledge of the 
relevant physics, and because of shortage of data.
  I do not drag in extraneous science and say it is applicable as a way of 
giving it credentials.  Non-sequitur refereeing is the bain of modern am and pro 
journal literature.  I do not say it is true until you show it not to be.  If 
you want an answer to everything regardless in a faith based way, you choose a 
religion.  There's nothing wrong with that.  If you want to assess things via 
scientific principle you have to realise that many questions cannot be answered 
simply because it is not possible to ask the question.

Cheers

John
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