24 Tauri graze observed north of Columbus, Ohio - New 2006 July 21

Several events were recorded in spite of poor transparency

Unfortunately, so far I know of no other successful observations of this spectacular Pleiades passage

For the Pleiades passage Thurs. am, July 20, bad weather was 
forecast along the path for the Alcyone graze Thurs. morning, July 
20th, from central Illinois to s.e. Michigan, so we abandoned our 
earlier plans to observe it and instead observed the grazing 
occultation of 6th-mag. 24 Tauri from sites along Road 21 about two 
miles northeast of Marengo, Ohio (about 20 miles north of Columbus).  
The sky there was clear, but very hazy and humid, with a naked-eye 
limiting mag. of about 3.  I recorded a minute-long occultation 
during the 24 Tauri graze, including two flashes (brief 
reappearance-disappearance) several seconds after the initial 
disappearance.  Hal Povenmire, farther south, had about a 78-second 
occultation, but a quick flash immediately followed the initial 
disappearance.  Wayne Warren was farther north and probably had more 
action, but he has not reviewed his tape yet and couldn't see 
clearly in real time with the small backlit screen of the video 
walkman he used to record the graze; the star was dimmed by dew on 
his telescope's corrector plate (he didn't realize until too late 
that he needed to use a dew cap, which was hard to get at the bottom 
of the box).  After the 24 Tauri graze, I video recorded about a 
dozen total occultations, including of stars down to 9.6 mag.; a 
couple of tenth-mag. stars were very faintly seen, but their 
occultations could not be timed due to the poor transparency.  
Unfortunately, bad weather actually developed along essentially the 
whole predicted path for the Alcyone graze in the USA and part of 
Ontario, and it was also mostly cloudy in the Washington, DC area.  
You can see infrared satellite views and maps of surface weather 
reports around 7:45 UT in this Power Point file.  So far, 
I have not heard of any other successful observations of the 
Pleaides occultations, either totals or grazes, which is 
unfortunate; we could have used help from local observers along the 
24 Tauri path that crossed Louisville, KY and the more populous 
parts of Ohio.  Extensive prediction information about the July 20th 
Pleiades passage, including predictions and maps of the area where 
we observed the graze, are here.
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David Dunham, 2006 July 21
Phones home 301-474-4722; office 240-228-5609; car 301-526-5590
emails dunham@starpower.net or office david.dunham@jhuapl.edu