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Re[2]: (meteorobs) meteors
---------------------------------- Forwarded ----------------------------------
From: Joseph Assmus at PACE-POST
Date: 11/5/96 9:47AM
To: pued@msndot com at @UCSD
Subject: Re[2]: (meteorobs) meteors
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11//5/96 @ 11:38am, you write: >Thanks, Joseph. But can't sporadics
intersect the radiant?
Sure they can, and do! I guess it partly comes down to statistical
probabilty. This is the caution in doing visual obs during major
and minor meteor showers. Say you're watching the QUAs one night in early
Jan. IMO lists a ZHR=120. If sporadics have a general ZHR ~6 or 7,
probabilty theory dictates that, given the zillions of meteors you'll see
that night, if a particualr meteor satisfies all the IMO crtieria for shower
association, than it is likely a QUA and not a SPO. However, if you're
watching, say, the July Pegasids (ZHR ~3) or the S. Iota Aquarids (ZHR ~2),
you must be VERY careful in making a shower association. During minor
shower observations, an observer's final tally has a higher probabilty of
containing SPORADIC POLLUTION.
AN EXAMPLE: If your hourly total for QUA wrongly contains 2 SPOs out of,
say, 73 QUAs, that's only 2.7% error rate (may be accepatble). But, if your
SIA hourly count total is, say 3, and it mistakenly contains 2 SPOs, then
you get 67% error rate (clearly unaccepable).
Joseph
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>Date: Tue, 5 Nov 96 11:38:23 UT
>From: "Thomas Wojack" <pued@msndot com>
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>Subject: RE: (meteorobs) meteors
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