Dear Colleagues-
 
Continued MACHO/GMAN monitoring of event 98-SMC-1 has detected an
ongoing deviation in the lightcurve.
 
Event                         98-SMC-1
Star ID                       208.15683.4237
RA      (J2000)               00:45:35.2
DEC     (J2000)               -72:52:34
V                             ~21.8
R                             ~21.7

The source star apparently underwent a caustic crossing due to a
binary lens near 5 Jun, and is currently in the region between
caustics, at a magnification of A ~9.  Predictions of future event
behaviour will be communicated as soon as they are known.

Resolution of the second caustic crossing will prove invaluable in
determining the proper motion of the lens, and therefore in estimating
its distance.  Spectral observations of the source star during the
crossing should be possible if the source is highly magnified.  This
will assist in the above estimate, and directly probe the chemical
composition of the SMC main sequence.

Observers are urged to immediately contact macho@astro.washington.edu
to coordinate photometric and spectroscopic observations.