This prediction update has been computed by Stephen Kerr based on astrometry from Ron Stone of the US Naval Observatory - Flagstaff Station. The Hipparcos position of the target star has been used.

Summary:

This update indicates a shift in the predicted path to the south of around one third of a path width relative to that given by Goffin with no change in time. Derby in Western Australia lies just to the south of the edge of the path (10:21:30 UT - local twilight) and Groote Eylandt in the Gulf of Carpentaria just inside the southern path limit (10:23 UT). Lae in Papua New Guinea lies on the northern limit (10:24:45 UT). Consult the map below for details of other areas.

• Date and approx. UT time of event: October 4, 2000 @ 10:22 UT
• Magnitude of target star: 8.60
• Magnitude drop [mag]: 0.3
• Estimated maximum duration [s]: 37.5
• Path description: See above.
• Goffin's original chart reference: A00_1001

• Approximate width [km]: 550
• Map: See below
• Circles along the path are OCCULT calculated exact centerline points !!!!

• Name: HIP 96940 = SAO 188469 = PPM 270168 = TYC 6898-2020
• Constellation: Sagittarius
• J2000 position [h,m,s; ^o,',"]: 19h 42m 23.522s; -26^o 26' 37.67"
• Position source: Hipparcos
• V mag [mag]: 8.60
• B-V [mag]: +1.35
• Remarks:
• The target star is in eastern Sagittarius. The target star lies 3 degrees to the west of the magnitude = 4.7 star omega sagittarii and 2 degrees south-east of the magnitude 4.6 star 52 sagittarii.

• Number, name: (4) Vesta
• Approx. diameter [km]: 501
• Source of used astrometry: US Naval Observatory - Flagstaff Station (Ron Stone)
• Number of used observations: 24
• Number of rejected observations: 0
• Time covered by the observations: 2000 05 26 - 2000 09 26

• UT date and time of least geocentric approach: 2000 October 4, 10:21.5 UT
• Approx. V mag of minor planet at event [mag]: 7.24
• Geocentric parallax of minor planet ["]: 4.79
• Magnitude drop [mag]: 0.3
• Estimated maximum duration [s]: 37.5
• Apparent motion of minor planet ["/h]: 36.05
• Angular distance to moon, phase of moon [deg,%]: 24, 40%
• Update computed by: Stephen Kerr (Win OCCULT 1.3).

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.