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Old 14-10-2007, 02:48 PM
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fringe_dweller
on the highway to Hell

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Join Date: May 2005
Location: Adelaide
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yes true it doesnt follow the meteor path length travelled one third of distance from radiant rule, but from NAMN notes

'c) METEOR LENGTH TO RADIANT RELATIONSHIP - The closer a meteor emerges from its radiant, the shorter in length the meteor will appear. If it appears right in the radiant, it will appear as a star suddenly brightening and then disappearing (known as point meteors). The further a meteor appears from the radiant the longer the path of the meteor normally appears. Associating meteors with a shower using meteor length is difficult at first, but with practice becomes second-nature. A useful rule to remember is one developed by the International Meteor Organization which states:

"For radiant elevations higher than 30° the apparent path length l of a shower meteor amounts at most to half the distance from the radiant to the start point. Consequently, the distance between radiant and start point of a plotted meteor on the chart has to be at least twice as long as the meteor path itself if the meteor is a suspected shower member."'

or the average speed for Orionids/parent body

and as you said its a shallow entry/earthgrazer, larger particle and they dont follow the rules so much? plus the path is foreshortened with regard to viewer as the radiant isnt above 30º

I checked out pedigree on some of those last year, and most complied

and i cant find it now, but as you said its a large radiant, is it a 10º diameter radiant?
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