A number of naked eye views of the sky showing how to find beta Vir have been prepared by Brian Loader and Steve Kerr for different locations along the path. Click on the links below ...

Observers with cam corders or other portable video cameras capable of imaging beta Virginis are strongly encouraged to do so. If possible, observers should use a shortwave radio or GPS derived time source for their observations (eg play WWVH on a radio recorded either by the video camera or on a tape recorder recording observer comments). Alternatively, record a standard AM radio signal from the list below. A coordinator in each region will record this standard radio signal and correlate it to a time standard. The preferred AM radio stations are:

In the case of an occultation, the combined light of the asteroid and the star will drop by 9.2 mag to 12.8 mag (the magnitude of the asteroid) for at most 3.8 seconds.

This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Ron Stone, TMO astrometry for the asteroid kindly provided by Bill Owen, astrometry for the asteroid kindly provided by Gordon Garradd, historical astrometry from AstDys, and the following catalogs for the star position: .

Additional details of this and other events are available at Steve Preston's website at http://www.asteroidoccultation.com/

• Event Rank : 99
  (The event Rank is a measure of the likelihood of observing an event. Currently, the Rank equals
  the probability of at least one successful observation by a team of two observers spaced 1/8 path
  width just inside opposite sides of the predicted path. This probability is a function of the size
  of the asteroid in the sky (in arc seconds), the uncertainty in the position of the asteroid, and
  the uncertainty in the position of the star. Eventually, the Rank will also consider factors such
  as the brightness of the star, the magnitude drop, and the duration of the event).
  
  
• Date and approx. UT time of event : 2003 Jun 24, 10:27 - 2003 Jun 24, 10:37 UT
  (Refer to map for your own location)
• Magnitude of target star : 3.6
• Magnitude drop [mag] : 9.2
• Estimated maximum duration [s] : 3.8
• Phase of moon, angular distance : 24 % sunlit, 143° distance
• Sun : 85° distance
• Rough path description : Australia, New Zealand

• Approximate projected width [km] : 83
• Uncertainty interval [path widths] : +/- 0.25 (1 sigma)
• Uncertainty interval approx RA,DE ["] : (+/- .014 +/- .011) (1 sigma)
• Uncertainty ellipse (major, minor, PA) : ( .014", .011", 99° ) (1 sigma)
• Remarks :

• Name : FK6 445 (Beta Virgo)
• Constellation : Virgo
• J2000 position [h,m,s ; °,',"]: RA: 11 50 41.8852 DE: +01 45 52.080
• Position source : Pos: FK6 (STP), pm: FK6 (LTP), pi:FK6
• Standard error : RA,DE ["]: ( .010, .008 )
• V mag [mag] : 3.6
• Remarks : (none)

• Number, name : (124) Alkeste
• Approx. diameter [km] : 76
• Approx. diameter [arcsec] : .044
• Source of used astrometry : FASTT TMO Garradd Astdys
• Number of used observations : 693
• Number of rejected observations : 72
• Time covered by the observations : 1902 Sep 03 - 2003 May 22
• 1 sigma uncertainty ellipse (major, minor, PA) : 0.010, 0.008, 109°
• Remarks :
• Update computed by : Steve Preston, Medina, Washington, USA. (OrbFit).

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.

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