(6) Hebe final prediction

Last updated on 1995 Dec 16

(6) Hebe will occult PPM 210815 on 1995/12/18 at 07:34:38.4 UTC (geocentric)

Prediction details. (21Kb). The event will be visible in Northern California through to central Idaho. The asteroid should be at about V=9.0 and the star is 8.5 so the flux drop should be about 50%. For an assumed radius of 96 km, a central chord would last 18.8 seconds. The predictions are based on transit telescope measurements made at the US Naval Observatory Station here in Flagstaff. So far we have 11 measurements of the star and 11 measurements of the asteroid. The correction to the ephemeris is present uncertain by 0.079 arcsec in right ascension and 0.086 arcsec in declination. We have generated postscript plots of the entire track (305Kb) and a plot of the southwest US (207Kb). The dashed lines are contours of constant target elevation at the time of the event (labeled from 10 to 25 degrees). At the northeastern limit the asteroid is too low to the horizon to observe. The catalog coordinates of the star are ra=01:54:54.043, dec=-11:30:40.74, J2000. This is the final prediction for the event. Given the weather conditions, a portable expedition will not be sent out from Lowell Observatory. Ted Dunham will try the event (weather permitting) from near the southern limit and the Crossley Telescope on Mt. Hamilton may be trying the event as well.

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.