Kazuo Kinoshita's calculation revealed that it passed close by Jupiter
in 1980 and the perihelion distance reduced from 2.5 A.U. down to 2.0
A.U. It was discovered because it became close to the sun.
In 1984 when it approached to the sun for the first time, it
brightened up to 14 mag and it was discovered. In the next return in
1991, it brightened rapidly up to 14 mag again. However, it was actually
so faint as 19 mag in the return in 2006, much fainter than before by 5
mag, although it was expected to reach to 14 mag again.
It kept the same brightness in two appearances. However, it suddenly
faded in 2006.
In the return in 1999, it was observed as 20 mag about 1 year after the
perihelion passage due to the bad condition. So it cannot say whether it
reached up to 14 mag, or only to 19 mag at best, at the periheolion
passage.