On Sept. 1, 1999, comet 106P/Schuster was rediscovered at Siding Spring Observatory in the constellation of Sculptor. The following analysis is based on 11 observations by 3 FG members and 60 international observations. According to these the comet reached a maximum brightness of 13.0m at mid-November 1999. The brightness parameters are only derivable with some uncertainty as m0=11.5m/n=4, due to the small variation in solar distance. The apparent coma diameter increased from 0.5' to 1.3' in January 2000, but had decreased thereafter to less than 1' at the end of the apparition. In contrast, the absolute coma diameter increased during the apparition continually from 20.000 km to 70.000 km. The DC-value was almost constant at DC 3, i.e. the coma was only moderately condensed.
Total Brightness and Coma diameter
Andreas Kammerer
