November 24th Steina Occultation Timed in Virginia

New: 2003 December 3

The occultation of 7.3-mag. SAO 91923 by 707 Steina was video 
recorded from locations near Bowling Green and Woodstock, and timed 
visually near near Massaponax, showing that the path shifted about 
1.2 path-widths north of its predicted path.  Woodstock is in the 
Shenandoah Valley near I-81; the other locations are in central 
Virginia south of Fredericksburg.  Several miss observations from 
other locations were reported from other locations farther south in 
Virginia, and from Morgantown, West Virginia; the observers, their 
locations, and timings are given in the Occult .obs file here.
I have fitted a 13.5-km circle to the observations shown here.
Station 1 is Joe Sedlak near Massaponax; 3 is John Brooks' video 
observation near Woodstock; and 7 is my short chord near the 
southern limit at Bowling Green (where Joan and William joined me, 
but without enough time for me to get that set up for them to run 
and go to another station).  But my one-second event was gradual due 
to Fresnel diffraction, with the disappearance lasting 0.30 second 
and the reappearance lasting 0.23 second; the star was totally 
occulted for only 0.67 second.  To show this, I've added chords 9 
(the period of total occultation of the star) and 10 (from start of 
the disappearance to end of the reappearance) to the plot, with 7 
being the point of geometric occultation (1/4th light intensity).  

Path 5 was Jack Littleton's miss observation at Morgantown, WV; all 
the other miss paths were farther south, covering the predicted path 
and southern uncertainty zone.  Path 6 is the path the star followed 
at the location of a remote telescope that I set up beside US 301 
surrounded by Ft. A. P. Hill, about 5 miles south of Port Royal.  
Unfortunately, I made a mistake reading the star chart for pointing 
that telescope so that at the time of the occultation, the telescope 
was pointed about half a degree too far south and did not record the 
target star.  Too bad; that would have provided a valuable northern 
chord to better determine the shape of Steina.  But another mistake 
was fortuitous - I had planned to observe farther south, but read 
the map plot incorrectly at the last minute in selecting the Bowling 
Green site; if I hadn't done that, I would have located farther 
south outside the actual path.  The homeowner at Bowling Green where 
I set up was very helpful and wants to get a copy of the videotape 
of my observation, which I plan to send in a few days, now that I 
have produced a time-inserted copy.

David Dunham