Edwin Goffin's original prediction indicates an event very favourably placed for south-eastern Australia, the shadow crossing the region of Adelaide and Sydney.

David Herald's OCCULT software suggests a path across Melbourne and not far from Tasmania and northern New Zealand.

IMPORTANT NOTE:

Jan Manek notes that there is need to be careful with this event as the star is a double star. The resulting magnitude drop will therefore be only 2.0 mag, rather than the originally expected 6.5 magnitudes, for telescopes unable to resolve the double.

The double star designation is BU 281. The secondary component is magnitude 9.1 and is in P.A. 168 deg with separation 1.55" from the primary.

UPDATE (8 December 1998):

This final update for this event has been computed by Jan Manek of the Stefanik Observatoy in Prague based upon 17 astrometric positions obtained by Bill Owen at Table Mountain Observatory between September 29 and December 3. The HIPPARCOS position of the star has been used, thereby essentially reducing any error in the star position to zero.

Path Update:

• The occultation track for the primary star continues to run south of New Zealand, about one track width from the bottom of the South Island;
• Predicted event time is 11h 32m for INVERCARGILL, NZ.
  
  
• For completeness, Manek has also calculated the occultation track for the secondary component of this double star system. The track runs across north-western Australia, although Manek notes: ...in this case either photometric equipment or a telescope which can resolve the double should be used so the full dropout of the secondary component will be visible. i.e. The overall magnitude drop if the secondary is occulted will be very small.
• Predicted event time is about 11h 27m for EXMOUTH, WA.

Uncertainties are currently about 1.0 path widths and 20 seconds of time, although due to the system's duplicity unexpected path shifts may still occur.

PRIMARY COMPONENT PATH UPDATE:

SECONDARY COMPONENT PATH UPDATE:

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.

[Top of Page][Return to Home Page]