This prediction update has been computed by Graham Blow based upon 11 astrometric position of the planet obtained by Ron Stone (USNO/Flagstaff) between June 18 and July 7. (Additional earlier positions were available but it was felt to be unsafe to use them with the OCCULT software). Reduction is against the ACT position of the star.

Summary:

• The update astrometry produces a path in good accord with Goffin's original prediction. The updated track crosses central New Zealand in the region of Wellington and Blenheim, and New South Wales in the region of Newcastle.
• Event time is about 2 MINUTES EARLIER than the nominal Goffin prediction, and 7 MINUTES LATER than the nominal OCCULT prediction.
• Formal errors on this path are relatively small because of the larger number of astrometric positions used.
• Approx time for Wellington and Blenheim: 08h 10m UT
• Approx time for Newcastle: 08h 15.5m UT
• Because the asteroid is slow-moving observers are recommended to observe for somewhat longer than they normally might do.

THE EVENT AT ONE GLIMPSE:

• Date and approx. UT time of event: July 12, 1999 @ 08:10 UT
• Magnitude of target star: 9.78
• Magnitude drop [mag]: 4.3
• Estimated maximum duration [s]: 6.2
• Path description: The path runs across the middle of New Zealand and enters NSW in the region of Newcastle.

• Name: TYC 7854 01595
• J2000 position [h,m,s; o,',"]: 16h 36m 25.487s; -38^o 23' 55.40"
• Position source: ACT
• V mag [mag]: 8.78
• Remarks:

• Number, name: (292) Ludovica
• Approx. diameter [km]: 35
• Source of used astrometry: USNO
• Number of used observations: 11

• UT date and time of least geocentric approach: 08:06 UT
• Approx. V mag of minor planet at event [mag]: 14.1
• Geocentric parallax of minor planet ["]: 5.44
• Magnitude drop [mag]: 4.3
• Estimated maximum duration [s]: 6.2
• Apparent motion of minor planet ["/h]: 17.48
• Angular distance to moon, phase of moon [deg,%]: 148, 1%

IMPORTANT NOTE!

Astrometric updates such as these should not be taken as definitive, but rather only as an indication of where the true track may lie relative to the original predicted track. Observers must bear in mind that later astrometry, in which the target star is measured in the same field as the asteroid, may still reveal substantial changes to the predicted track and time of the event. For this reason it is most important that observers far from the predicted track still monitor the event.