(meteorobs) Meteor Activity Outlook for October 12-18, 2007

[meteoreye at comcast.net]

joe,
OK I did some checking.
First, I'd be surprised if those figures quoted by Paul Roggemans were ZHR's, since of course back then data was not recorded in a format compatible with calculating true ZHR's. However I don't have a copy of the 1989 Sky Pub version, so have to leave that interpretation up to you.

In the 1995 IMO Handbook for Visual Meteor Observers (Roggemans was one of the editors)that table is not included.

In the article in WGN 35:2 by Jurgen Rendtel that I referred to, he lists 2 hints of enhanced activity.

One is from A.C.B Lovell's 1954 Meteor Astronomy, which I do have.

Fig 141 (p.289) shows hourly rates (not ZHR's) for a year of low activity (1928) (highest HR ~ 6) and years of high activity (1938 highest HR ~ 20).
Interestingly, he uses Prentice as a reference.
He states "An extensive study of the shower between 1928 and 1939 has been made by Prentice.
(JBAA 1933,1936,1939,1941) The activity from 1928 to 1935 was very low, but it increased rapidly between 1933 and 1935."

Fig 142 shows the enhancement peaking in 1936

The other source that Rendtel mentions is: "Millman (1936) shows Orionid rates observed at Bologna by M. Loreta with a peak rate of 50 on 1936 October 22. The rates on the days before and after the maximum are also relatively high and may this hint at a similar profile as we found it in 2006. The non-Orionid rates of about 10-15 in most periods indicate there is no significant over correction of the Orionid rate."

Rendtel admits it is a relavtively small sample of observational reports, but it does seem there may be something there.

The article from the Astronomical Society of Japan that I mention includes the reference to Loreta's observations above, and well as a report by M.H. Wright in Popular Astronomy (1936) 44, 570

who "observed a remarkable shower the night of 1936 October 19. "

Anyhow, that's what I found

Wayne
-------------- Original message -------------- 
From: Skywayinc at aol.com 

> 
> In a message dated 10/11/2007 4:02:13 P.M. Eastern Daylight Time, 
> meteoreye at comcast.net writes: 
> 
> This resonance may explain enhanced Orionid counts from 1936-1938 from the 
> previous orbit of this concentration (~ 72 years). 
> 
> 
> 
> --------------------------------------------------------- 
> I have been doing some research and cannot find any reference that points 
> toward such enhanced Orionid counts from 1936-1938. In "Handbook for Visual 
> Meteor Observations," edited by Paul Roggemans (Sky Publishing Corp. 1989), we 
> find on page 151, a table listing Orionid activity from AD 585 to 1987. For 
> 1936, we find a ZHR of only 12 and in 1938, just 19 (there was nearly full 
> Moon in 1937). So, if anything, in at least two out of three of those 
> "enhanced years" the Orionid ZHR was below-to-much below the oft-quoted figure 
> of 25! 
> 
> -- joe rao 
> 
> 
> 
> 
> 
> 
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