The brightness parameters of comet C/1999 J2 (Skiff), a record breaking object regarding the perihelion distance, are still indeterminated. This may probably last for several years, until the solar distance variations, necessary for the determination, will reach a certain amount. The most plausible values are still m0=1.5m/n=4. According to the 6 visual observations by Werner Hasubick and 140 international estimates the maximum brightness of 14.1m was reached in May 2000. The coma had a diameter of 0.9' (300.000 km) prior to perihelion, and of 0.8' (250.000 km) afterwards. The DC value was constant at DC 3-4. Since the conjunction with the sun in November 2000 visual observations were scarcely published. Since the beginning of the year 2001 a small number of CCD-observations of this comet had been published. According to these the brightness was around 16.5m with the comet displaying an apparent coma diameter of 0.5'. All these observations are consistent if it is assumed that this comet is now about 0.5m fainter than proposed, being fainter than 15.5m in October 2001.
A team on the National Astronomical Observatory of Japan observed a 3' dusty anti-tail at the end of April / beginning of May.
Total Brightness and Coma diameter
Andreas Kammerer
