(99) Dike Occultation Dec. 1 observed in Maryland & Virginia
The predicted path was accurate and SAO 58354 was found to be a close double star
Two pre-pointed telescopes, including one at home and one remote, video recorded the occultation
Clips from my three video tapes showing the occultation are now here
Updated: 2005 Dec. 7
The prediction for the occultation of HIP 26902 = SAO 58354 by (99) Dike the morning of Dec. 1 turned out to be very accurate, as one might expect for a relatively bright HIP star and low-numbered asteroid. The weather forecast was also good - clouds started moving into the DC region only a few minutes after the occultation. I set up an 8- in. SCT with McAfee GPS time insertion, pre-pointed, in our back yard in Greenbelt, MD; my wife, Joan, connected the camcorder and started recording a few minutes before the event. I set up a similar system as a remote station, with Kiwi time inserter, near La Plata, MD. Then I observed with a 5-in. SCT near Dahlgren, VA, with WWV recorded. The camcorder I planned to use failed to start recording 5 min. before the event, but I managed to switch to another camcorder with a weak battery a couple of minutes later. Fortunately, that battery died after the event. The recording at home shows distinct step events, showing that SAO 58354 has a faint companion, maybe 10th mag., a short distance north of the star. Joe Sedlak, who was midway between my La Plata and Dahlgren stations, timed the occultation visually, as did Bob Wetmore in Bethesda, MD, about midway between my home and my La Plata remote station, relative to the path. Since only two-second occultations occurred at both my home and my site near Dahlgren, those sites were close to the occultation limits and we have 5 chords very well-spaced across the asteroid. Wayne Warren video recorded the appulse from the Goddard Optical Facility only 3.5 miles northeast of my home and had a miss there, establishing the actual northern limit very well (it was predicted to pass between those two locations). Gary Frishkorn, in Dayton, MD, was a little farther north relative to the path and also had no occultation. Unfortunately, observers not very far northwest were clouded out. A brief summary so far: Steve Preston's 11/03/05 update Occultation of HIP 26902 by 99 Dike on 2005 Dec 01 Distance from center of occultation path - in km Proba- Location km bility 71 16% ** Northern limit plus 1-sigma ** 44 43% Dayton, MD Gary Frishkorn - no occultation (miss) 38 49% GORF16IN Be Wayne H. Warren - no occultation (miss) 35 49% *** Northern limit *** 33 55% GREENBLT MD Joan B. Dunham - 2s occ'n, in steps 17 67% Bethesda MD John Wetmore - 4s occ'n -6 La Plata MD Dunham remote - 5s occ'n -16 Chapel Pt. St. Park MD Joe Sedlak - 4.8s occ'n -29 Dahlgren VA David Dunham - 2s occ'n -43 49% *** Southern limit *** For the stations, but not the limits, you need to add 4 to the distances to convert them to Preston's last prediction issued about 0h UT of Nov. 30 UT. I hope that there might be some additional observations of this event; if you didn't observe from the DC region, you missed a good one. The clear weather here was payback for the 3 events over the region in October that were all clouded out. Very large .avi files (you need a high-speed connection) showing a few seconds of my videos are below: Greenbelt, MD, 8" SCT, 48 megabytes La Plata, MD, 8" SCT, 83 megabytes Dahlgren, VA, 5" SCT, 38 megabytes Extensive prediction information is here. David Dunham e-mail home dunham@starpower.net; office david.dunham@jhuapl.edu