THE UPDATED PATH

This updated path lies around four path widths to the southeast and around 15 seconds later than that given by Goffin. The new path crosses the north Queensland coast around Townsville at 12:46:30 UT running to the southwest to the Alice Springs area at 12:48 UT. The path emerges from the Western Australian coastline between Geraldton and Shark Bay around 12:49 UT at a lowish altitude of around 15 degrees.

As there have been only six astrometric positions used in this calculation, the error margin for this event is quite large with Perth an outside chance for an occultation around 12:49 UT.

Observers are reminded that the target star is quite faint and observers with smaller telescopes may struggle to monitor this event.

Calculation Source

This prediction update has been computed by Steve Kerr, Rockhampton, Queensland, Australia based on astrometry from Ron Stone of the US Naval Observatory - Flagstaff Station. The Tycho 2 position of the target star has been used.

• Date and approx. UT time of event: 2002 January 5 - 12:47UT
• Magnitude of target star: 12.23
• Magnitude drop [mag]: 1.4
• Estimated maximum duration [s]: 10.5
• Angular distance to moon, phase of moon [deg,%]: 46, 57%
• Goffin's original chart reference: A02_0149

• Approximate width [km]: 150
• Uncertainty [path widths]: +/- 2 (95% certainty - asteroid position only)
• Remarks: Uncertainities are given on the basis of the expected asteroid positional accuracy ONLY.

• Name: TYC 6048-00459-1
• Constellation: Hydra
• J2000 position [h,m,s; ^o,',"]: 9h 45m 32.426s; -17^o 00' 57.69"
• Position source: Tycho 2
• V mag [mag]: 12.23
• Remarks:
• The target star is in central eastern Hydra. The star is 2.6 degrees southwest of upsilon 1 Hydrae (magnitude = 4.1).

• Number, name: (895) Helio
• Approx. diameter [km]: 147
• Source of used astrometry: USNO - Flagstaff Station (Ron Stone)
• Number of used observations: 6
• Number of rejected observations: 0
• Time covered by the observations: 2001 11 16 - 2001 12 10
• Update computed by: Steve Kerr, Rockhampton, QLD, Australia (Win Occult V2.0)

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.