Occultation by (1354) Botha on October 9 - new 2003 Nov. 11

The actual path was about halfway between Preston's and Manek's predictions

The occultation of 9.0-mag. SAO 109453 by the 53-km (expected) asteroid 1354 Botha was video recorded at the Astrolab-IRIS II Observatory near Ieper, Belgium (lat. 50 deg. 49' 13" N., long. 2 deg. 54' 41" E., height 45m); the 2.18-second occultation began at 2h 53m 11.05s UT determined with a Cuno DCF-77 time inserter. Click here for some images from the video and some other details. This location was about halfway between the last predicted paths by Steve Preston and Jan Manek, which were separated by about 2 path- widths. Unfortunately, it was cloudy across most of the path in both Europe and the USA. But David Vansteelant was able to monitor the star at the right time and saw no occultation at Bruges, Belgium (lat. 51 deg. 11' 37" N, long. 3 deg. 08' 42" E.), indicating that the Astrolab Observatory was probably near the northern limit. Roger Venable also managed to make a negative observation near Steve Preston's predicted northern limit at Swainsboro, Georgia. Botha's predicted diameter was 48 km, but a circle this size is too large to fit the Ieper observation without an occultation also occurring at either Vansteelant's or Venable's position. A circle with diameter 41 km does just fit the Ieper chord and Venable's miss, as shown in the sky-plane plot here, where "1" is the Ieper chord, 4 is Venable's miss line, 2 is Vansteelant's miss line, and 3 is the more distant miss by Henk Bulder in the Netherlands. The points 7 and 8 are the predicted points by Jan Manek computed with observations through Oct. 1 and Sept. 25, respectively. The points 5 and 6 are predicted points by Steve Preston on October 7th, using observations through Oct. 1. The plot shows Botha's center being a little closer to Preston's prediction, but it is almost equally plausible that the Ieper chord was near the southern limit with the northern limit very close to Vansteelant's line. Or Botha may be a rather elongated ellipse, longer in the north-south direction (perpendicular to the motion) and shorter in the east-west (along-track) direction. The Occult .OBS ASCII text file is here.