Prediction details. (21Kb).
The event will be visible in a swath from central Arizona through
central Kansas and lower Michigan. The asteroid should be at about
V=11.5 and the star is 8.6 so the flux drop should be very large. For
an assumed radius of 80 km, a central chord would last 17.5 seconds.
The predictions are based on transit telescope
measurements made at the US Naval Observatory Station here in
Flagstaff. So far we have 15 measurements of the star and 18
measurements of the asteroid. The correction to the ephemeris is
present uncertain by 0.066 arcsec in right ascension and 0.054 arcsec
in declination. We have generated postscript plots of the entire track (307Kb) and a plot of the southwest US (221Kb). The western end of the track is
defined by where sunset occurs at the time of the occultation. This
means that observers in all of Arizona and most of New Mexico will have
to fight strong twilight to be able to see the event. On the plot of
the southwest US, there are a series of lines indicating the elevation
of the Sun at the time of the occultation. The lines run from -6
degrees (civil twilight) to -16 degrees (nearly astronomical
twilight). The catalog coordinates of the star are ra=03:31:01.445,
dec=+07:11:54.05, J2000. Additional transit observations are being
taken every night possible at USNOFS and updated predictions will be
posted here.
The prediction team consists of Ron Stone at the US Naval Observatory
providing transit measurements, Larry Wasserman at Lowell Observatory is
processing the measurements and generating the predictions and plots, and
Marc Buie, also Lowell Obs., is coordinating the collection and dissemination
of information (like this WWW page). Direct comments and questions to
Marc Buie.